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Very quick update - my new fasteners arrived the other day, so I've steadily been able to swap-out the old fixings for the new ones. Nothing spectacular to see here, none of them are even shiney, just a dull almost galvanised finish. Hard to dress up what £600-worth of nuts'n'bolts looks like, but here's some pics anyway, just to prove I got them, haha.
https://img.photobucket.com/albums/v...7BDE0348A6.jpg https://img.photobucket.com/albums/v...36456778EB.jpg As mentioned previously, effort is going into the house project right now but I have almost finished making the steering rack stops. And still not rigged up the plating kit. Hmmppphh. I'll post pics of the front suspension build when I'm further along, it'd just be a spot-the-difference competition otherwise. |
Ouch! Did some tiny purebred German gnomes from the Ruhr area bend over and $hit those out of their magic little bung holes to justify that price?
All good ... small price to pay for safety ... I'm just being a pillock. John |
Hi everyone, long time/no update, sorry about that, been busy on other projects (motorbike, work, etc) but let’s have a go at trying to remember the last year or so….
Update Part 1 – Chassis So, the last time I updated the thread, back in the middle of the U.K.’s “Lockdown #1” in 2020, I’d just received the consignment of replacement fasteners for the suspension refresh. Until then, it was assembled but using old fixings that had been stripped of plating and rust, and potentially ready for re-plating. Here you go, a load of semi-random photo's I took along the way. First off, the plating setup for the parts I was comfortable refurbishing... https://hosting.photobucket.com/imag...080&fit=bounds https://hosting.photobucket.com/imag...080&fit=bounds https://hosting.photobucket.com/imag...080&fit=bounds https://hosting.photobucket.com/imag...080&fit=bounds https://hosting.photobucket.com/imag...080&fit=bounds https://hosting.photobucket.com/imag...080&fit=bounds Steering lock stops in-situ on the rack... https://hosting.photobucket.com/imag...080&fit=bounds Rear suspension bearing retaining plates https://hosting.photobucket.com/imag...080&fit=bounds |
Hi Spence
Worth the wait I guess - Ridicules as time flies. Anyways, really, really happy for you. Looking fwd to further updates ;) Cheers Jesper |
The rear suspension plates were plated by the guys I usually use; by this point companies in the UK were starting to open back up. These were just too large to fit in my plating tanks (and maintain the right proximity of the anodes)
https://hosting.photobucket.com/imag...080&fit=bounds All assembled with the new Elephant Racing bush pack... https://hosting.photobucket.com/imag...080&fit=bounds https://hosting.photobucket.com/imag...080&fit=bounds Some more progress shots of the front and rear suspension being rebuilt... https://hosting.photobucket.com/imag...080&fit=bounds https://hosting.photobucket.com/imag...080&fit=bounds https://hosting.photobucket.com/imag...080&fit=bounds https://hosting.photobucket.com/imag...080&fit=bounds |
Front suspension....
https://hosting.photobucket.com/imag...080&fit=bounds https://hosting.photobucket.com/imag...080&fit=bounds https://hosting.photobucket.com/imag...080&fit=bounds https://hosting.photobucket.com/imag...080&fit=bounds Elephant Racing bump-steer "correcting" (assisting) rod ends... https://hosting.photobucket.com/imag...080&fit=bounds |
Next challenge was to make a tool that I could use to torque the spring plate pivot bolts with. Access on the RHS is very tight (it's asymmetric, left to right)...
https://hosting.photobucket.com/imag...080&fit=bounds So, time to get creative and hack around a spanner and other sundries... https://hosting.photobucket.com/imag...080&fit=bounds https://hosting.photobucket.com/imag...080&fit=bounds https://hosting.photobucket.com/imag...080&fit=bounds https://hosting.photobucket.com/imag...080&fit=bounds https://hosting.photobucket.com/imag...080&fit=bounds And then you can get it into the hex just fine. A quick re-calculation of the required torque, and job's a goodun' https://hosting.photobucket.com/imag...080&fit=bounds If memory serves, swapping over the old fasteners for new ones was very easy. The next job once Covid restrictions allowed was to drive the car across town to get a pal of mine to set up the geo very approximately to 964 RS settings. Although he has a laser alignment rig, it’s not a setup like a specialist chassis setup operation has….so this really was just a case of getting the car in the ball-park, usable and driving in a safe non-shopping-cart kind of way. Which we did, and I did get some use out of it between lockdowns in summer 2020. |
And this leads on to quite a nice piece of “going full circle” task, which was to make good on a commitment, or rather an intention, I made 10 years earlier! When I first bought the car in early 2011, the very first jobs that were undertaken were to do basic servicing, plus other odd jobs like sorting a snapped exhaust manifold stud, remove the (badly) leaking air pump system, fix the A/C and so on. The next piece of work I had scheduled was to replace the original Boge dampers for some Bilsteins (I think I mentioned this a long time ago in a previous write up). At the time, these were going to be supplied, fitted and then fully setup by an excellent family business over here called Centre Gravity. I’d worked with Chris and Jane before, doing several geometry/ride height/corner weighting setups on my previous 996.2 GT3. Chris is an absolute legend in UK Porsche circles – the word “tolerance” simply doesn’t exist in his lexicon; it’s either spot-on, or it’s wrong. Simple as that. And we’re not just talking about setting up to Porsche’s “book” numbers, this is using their experience and truly understanding the principles of chassis dynamics, using judgement and experience to set a car up. On the GT3, I’d been at their workshops as late as 11/12.00 midnight, still refining a setup and test driving it. He, and now his son-in-law Pete, really are suspension-whisperers. They don’t do restoration or engine projects, they do suspension and only suspension, and boy do they do a great job. (I’m a fan….can you tell?)
Anyway, Bilstein at the time were having supply issues, and so to get the ball rolling I sourced a set of dampers from Gert at Carnewal in Belgium (another really nice guy to deal with)…..then, because Centre Gravity are so popular, the soonest suspension slot I could book was some months away in early 2012. No problem (I thought), I’ll just crack on with the simple EFI conversion in the meantime…….er…..yeah right. And so, after 10yrs of this project, I was able to make that booking with Centre Gravity, and get the car up to them. In the interim, my thoughts on the chassis post-refresh were actually really underwhelming. In fact, not for the first time, I was mentally preparing myself to sell the car if this was the best I could get from it. After all that work with upgrading the suspension, it still felt leaden, uncooperative and frankly, dull as ditchwater. I’d read many threads over the years about the benefits of the narrow bodied Carrera chassis (of course being the basis for the legendary 964RS) as well as another modification to the Turbo chassis being to source (!!) Carrera trailing arms to narrow the trak, then using mega wheel offsets to fill the arches. I confess to this being a nagging pair of thoughts; was this ever going to be anything other than “meh”? BUT….I had to keep reminding myself that despite the new parts now being bolted to the car, it’s still unfinished. You know what they say, “Children and fools see things half-done”, so all I had to do was bide my time until chassis setup day. Other concerns were that the engine calibration still felt peculiar. If driving it over a weekend for a couple of days, then it’s fair to say that I got used to it, but actually this was learning to drive around the problems. Midrange throttle and WOT were fine, but the slow speed driving around town, in traffic, even parking, were becoming a ballache. It felt very much like a binary throttle, unpredictable and often stalling….but….one job at a time, eh Spence? The big day came in mid June (2021). My little roadtrip would see me travel up country (I also managed to squeeze in a visit to the National Motorcycle Museum, well worth a visit) for an overnight stop before arriving at Centre Gravity early the next day. First job upon arrival was for Pete to take the car for a solo drive and get a baseline reference. Encouragingly, when I asked him for his thoughts when he returned, the conversation went something like…. [me] What did you think of it Pete? [Pete] Er, how honest do you want me to be Spence? [me] Please, give it to me straight… [Pete] It’s utter sh**....let me get to work on it. …and the wave of relief was immense. If he’d have replied that was about as good as the Turbo wide-body’s get, then my next job would’ve been to draft the For Sale advert. A few hours later, and having had a great chat with another customer who was getting his Cayman set up (hey Charlie!), I could hear Pete taking it for another test drive, then handing me the keys and asked me to take it on a specific cross-country test route. Thirty minutes later I returned, physically shaking and with the biggest grin on my face. Of the cars I’ve owned, this is now my high-water-mark of sublime handling…even my Lotus Exige now feels like it now needs some damping adjustments to let it breathe with the road a little more. ('scuse the oft-trotted out cliche) No further adjustments required by Pete, it was spot-on….I paid my bill and headed off to my second destination a very happy customer. Something interesting that became apparent, was that because the chassis now felt so much more communicative and confidence inspiring, the engine became quite different to drive. Because I was able to carry more throttle into corners and not have that “confidence lift”, the engine felt smoother, not losing boost and therefore not having to transition through that awkward rev range. Was I able to now live with the calibration, I wondered? |
Some more photos of the suspension completely reassembled. Actually was really rather proud of my efforts on this, if only it would stay this clean and nice.
The Tarrett drop links did have the rubber boots installed; definitely a knck to doing them but easy enough once you do the first one. Not long after these photos were taken, I then sprayed everything with the waxy Dinitrol (clear) protective coating. Which instantly makes it look grubby! Oh well, it'd there to do a job I guess. Rear suspension.... https://hosting.photobucket.com/imag...080&fit=bounds https://hosting.photobucket.com/imag...080&fit=bounds https://hosting.photobucket.com/imag...080&fit=bounds https://hosting.photobucket.com/imag...080&fit=bounds https://hosting.photobucket.com/imag...080&fit=bounds https://hosting.photobucket.com/imag...080&fit=bounds |
Are those helper springs (near zero rate) on the dampers?
If yes, the helper springs really should be on the damper body end instead of the shaft end. |
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As you say, feel happier knowing that the fasteners are all new now. No way of telling how many times they'd been tightened/loosened and (dare I say) over torqued perhaps, during their life. Hope you're well mate, my next job is going to be to catch up on your thread ;) S |
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Yeah I was really having to stretch my memory back whilst writing this; the sequence of events and that "lost year" of Covid lockdown really plays tricks with trying to remember how things played out. More updates coming soon! S |
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Well, the reason the helper springs should be on the body end becomes clear when you push the coupler (the piece between the two springs) laterally. If the coupler is on the shaft, it can move quite a bit more than if it were on the body. In other words, the spring to spring interface is more robust if it happens on the body of the damper.
In droop situations while driving, the spring is not as likely to stay centered if the coupler is on the shaft end. I saw one car almost destroy the coupler due to spring movement. The problem was immediately solved by putting the helper spring at the body end of the damper. The more droop you have, the more pronounced the centering problem is. I just sent my dampers in for a refresh and had the droop reduced to 2" front and 3" rear. Now the helper springs are more compressed than they were so the likelihood of a spring centering problem is reduced. Nonetheless, I still mount the helper springs on the body end as there is no chance for a problem even at full droop. Sure, this problem is more likely to happen on a race car, but why not eliminate the possibility? |
Part 2 – Driveability
My next stop on the mini roadtrip was to drop the car off with Troy at Northampton Motorsport, who are only about 30-40 miles south of Centre Gravity. Troy and I had been speaking about leaving the car with them, for him to use as his “daily”, driving it to and from work in mixed traffic on a variety of slow and fast roads to then refine the mapping. From this he could then mentally note areas that needed work and make those changes (sometimes with Chris, his son, driving whilst he adjusted the maps live from the passenger seat). If ever there’s been a case of one car almost breaking a mans will to live, I think this might have been it for Troy! Many many hours of driving, refining, testing, refining and re-testing were spent, but eventually he called and said that he thought he’d improved it quite a lot, but not really to his satisfaction. Troy’s a great guy, absolutely no bulls**t and calls it how it is….no over-enthusiastic smoke and mirrors….I’d go as far as saying that he does himself a disservice by under-playing what he does. However, his initial thoughts that an improvement had been made were quashed when Chris then drove the car (Troy riding shotgun with laptop), and all of a sudden Chris was stalling the car and struggling with the same driveability issues. Ugh. [head-in-hands]. Troys theory that he may have just got used to driving it, were perhaps spot-on. I remember Troy phoning me one day when I was on the motorbike, midway through a week-long tour, saying that he was running out of ideas, and *perhaps* it was down to the injectors being too large, requiring too low a duty cycle at low engine speeds. He wasn’t convinced this was the case, it was more of a hunch but suggested another session on the dyno with smaller injectors. I have to confess, this wasn’t really music to my ears but it did seem like a pragmatic way forward – we had to try something, or just be satisfied with how it was. BUT…..their dyno was now fully booked until November, as they were cramming in bookings before having to shut the dyno cell for 3-4 weeks for noise insulating work to be undertaken. Three other tasks I asked Northampton Motorsport to look at were: T1) The inconsistency with battery life. Sometimes, if I forgot to put the trickle charge on the car, a few days later it would be fine and fire up no problem. Other times, the battery would be utterly drained. I’d tried checking current draws but couldn’t find anything immediately obvious. Things like the car remaining “live” for a few minutes after the doors being shut were working as expected, my suspicions layed with the ECU not being powered down, or rather, being kept live. T2) To resolve an issue where the engine idle speed would go into complete “hysteresis” when the A/C was switched on. Very odd, it would just hunt up and down and never quite gather itself and settle down. T3) To try and finally get the rev counter to work. It had previously worked just fine with the old MBE ECU on Build #1, but had never so much as flickered into life with the Syvecs, annoyingly. The guys there did an awesome job, they really did. Candidly, these were jobs I just didn’t have the willpower to keep going at. Fixes thus…. F1) I’d tried diagnosing the battery current drain, and wasn’t seeing anything obvious. Chris spent some time working it, and did find some wiring strangeness with the ECU harness. I have to admit, I can’t remember exactly what it was, but whatever he found was occasionally keeping the ECU from powering down after engine shut-off. He’s pretty handy with making looms himself, so I had confidence to just let him get on with it and resolve, which he’s done. I’ve had the car back since the 22nd December, and not once had it on the battery tender, with no starting issues. F2) Whilst in the mood for wiring, we got our heads together and found a way to overcome the idling issue. By taking a feed from the A/C compressor clutch, and using that as a signal into another input of the ECU, we can now detect the additional electrical load and switch to a higher target RPM map. It works flawlessly; activate the A/C and it’s undetectable that the engine will then switch across and run a few hundred RPM higher. We’ve tested it with not only the A/C but also windscreen wipers, headlights and main beam lamps all switched on simultaneously, and there’s no stalling or fluctuation of the idle. F3) This one was *fairly* straightforward for Chris to investigate…. [Background story…] I just realised that it was a year ago when I had a few spare moments over the Christmas/NY break, and decided to have another go at trying to get the tach working. No idea what I did, but when I went to start the engine again, there was absolutely nothing. It cranked but no sign of bursting into life. I bit the bullet and dropped the ECU off with Syvecs for them to diagnose, and I’d done a proper job (!!) and blown both drive-by-wire outputs and an onboard fuse, lol. A week later and £130 lighter, and the ECU was back with me and back to normal. Time for me to hand this little issue over to somebody else. So, according to the SCal s/w, the tach driver output from the ECU was setup correctly, the output pin and number of pulses all checked-out OK. All fingers pointed at the rev counter itself. Not what I wanted to hear, as getting this repaired was going to be a right pain….1980’s/90’s tech is long forgotten, so I thought. Big thanks to Matt at Fearnsport who very kindly lent Chris a known-good 964 tacho for us to test with. Per Chris’s suspicions, within 30secs of plugging it in to my car, we had a needle doing its thing and reading correctly. Arse. In terms of repairing, I had a tentative lead on the guy in Germany who actually worked for VDO at the time and designed this exact unit. However, this turned out to be bloody slow in terms of reaching out via somebody else, to persuade him to take on this job. Like a lot of the specialists out there, because of the current trend to restomods, they’re inundated with work and getting choosy as to what they want to do. Luxurious position to be in. Wish I could do the same [tut]. I went up to retrieve the rev counter, got back home and opened it up. Yup…..I think we’ve found the smoking gun….. <a href="https://photobucket.com/u/spenny_b/a/f73e13cd-fc3e-4dde-a69a-ea5049418dbd/p/03feeb10-a3fc-4ad1-a440-2f5beb930869" target="_blank"><img src="https://hosting.photobucket.com/images/v229/spenny_b/IMG_2826_2.jpg?width=960&height=720&fit=bounds" border="0" alt="IMG_2826_2"/></a> <a href="https://photobucket.com/u/spenny_b/a/f73e13cd-fc3e-4dde-a69a-ea5049418dbd/p/560045b4-f30e-4d17-b392-dcdaa2d2790a" target="_blank"><img src="https://hosting.photobucket.com/images/v229/spenny_b/IMG_2825_2.jpg?width=960&height=720&fit=bounds" border="0" alt="IMG_2825_2"/></a> <a href="https://photobucket.com/u/spenny_b/a/f73e13cd-fc3e-4dde-a69a-ea5049418dbd/p/ef224f9d-ade6-49d5-979b-7639c25176e4" target="_blank"><img src="https://hosting.photobucket.com/images/v229/spenny_b/IMG_2823_2.jpg?width=960&height=720&fit=bounds" border="0" alt="IMG_2823_2"/></a> <a href="https://photobucket.com/u/spenny_b/a/f73e13cd-fc3e-4dde-a69a-ea5049418dbd/p/a8f78fee-73d8-408b-a157-ae2556e5ccaa" target="_blank"><img src="https://hosting.photobucket.com/images/v229/spenny_b/IMG_2822_2.jpg?width=960&height=720&fit=bounds" border="0" alt="IMG_2822_2"/></a> Having retrospectively trawled the forums and thanks to John (304065), we found that this isn't an isolated incidence, it's been seen before. Not sure whether it's something that just happens under certain conditions or whether we accidentally stuck 12v up its arse when the wiring harness guy and I were trying all sorts of things to try and get it working. Who knows. I then had a brainwave. Good old Tore over in Norway, from Bergvill F/X! I’d liaised with him a number of times some years ago, he’d been helpful in diagnosing and fixing my HVAC, and I’d also bought a few things from him too. As it happens, he now has all the diagnostic and test gear to repair these units. He also took care of the shipping paperwork (sounds a menial task, but post-Brexit it really isn’t….incredibly frustrating and time consuming while we all get our heads around the new system). It was exactly 1 week between the rev counter leaving me and then receiving a lovely DHL parcel with it all repaired. Not only did he replace the blown components, and repair the PCB track that had vapourised, he also did some preventatively modifications to the OBC components on the board below, as these are known to expire. A new set of bulbs fitted and it’s now got a guarantee. |
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ID1050-XDS - Injector Dynamics There are no better injectors and they have worked phenomenally well on my 431 HP normally aspirated race car. |
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How much power are you making? What ECU are you using? |
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Part 3 – Engine Healthcheck….and more…
The delay in proceedings and having to wait until after the dyno cell upgrades were finished actually turned out to be extremely beneficial. With the mileage on the rebuilt engine, it was a good time for Matt @ Fearnsport to inspect the engine and do an oil change. In fact, my ask of Matt was more than that… 1. Leakdown & compression test the engine 2. Set valve gaps 3. Check head stud torque 4. Change the engine oil 5. Send an oil sample away for analysis 6. Fit new smaller injectors. I hadn't actually ever got around to selling the original set of Siemens Deka 630cc injectors from Engine Build #1, so I thought I'd send these up to Northampton for cleaning and swapping into the car. Unfortunately they wouldn't clean up well enough despite many cycles. The closest they'd recover to was with a delta of 6% across the set. Nowhere near, which was a shame, as they certainly delivered the numbers many years ago and were practically new. Northampton Motorsport, by coincidence, had a set of 8x Bosch injectors in stock, that had been measured on their injector rig. By selecting the best 6, we had a delta of <1%. There was also one more interesting additional job…..(prepare yourself, it's another anecdote...) When Chris (Northampton Motorsport) was solo driving the car down to Fearnsport (Silverstone circuit, about 10-15miles away) he was able to reconcile some thoughts on how the engine was driving, without interruption from somebody wanting to do live calibration tweaks. Apparently, when he arrived at Fearnsport and chatted with Matt, he queried the eThrottle pedal and whether it was perhaps broken. When Matt then informed him that the car didn’t have an eThrottle pedal but was still running the OE cable throttle, the lightbulb moment happened. As long time readers may remember, many years ago I swapped out the Porsche throttle linkage on the engine for one I fabricated myself. It took many days to build and weld, and was done to accommodate an Audi eGas potentiometer, a rotary device operated by a short cable. I spent a lot of time getting the leverage ratios correct and bushing the pivots to make it as slack-free as possible. Way-back-when I do remember having a conversation about trying to use a BMW eThrottle pedal but dismissed it as looking too aftermarket and possibly not even fitting. Consequently, I’ve always used a setup thus: OE Pedal >>OE (and original) throttle cable to engine bay >> Actuating my home-brew linkage >> In turn actuating the Audi potentiometer >> Then the electronic signal from pot to ECU to 997 throttle body. With the lengthy cable, throttle linkage “play” and then the short Audi cable, it’s little wonder that Chris described the driveability being like the engine is disconnected to whatever his foot was doing at the throttle pedal. Kind of kicking myself now. Like everything, hindsight is 20/20 and a wonderful thing. As it happens, Matt had also investigated using a BMW pedal in another customers car (a lovely “Altzen” 964 RSR). I don’t mind admitting that I rather too hastily dismissed the use of said pedal back in the early days of this project. It looks absolutely stock when mounted correctly, as Matts other customer will also attest. So….Job #7 for Matt was to mount an E46 BMW pedal that I sourced, and get it wired up to the ECU. This was done, and I think you’ll agree, looks “factory”….. https://hosting.photobucket.com/imag...720&fit=bounds Wiring is actually run back from the new pedal to the engine bay and interfaces to where the Audi unit was connected previously. If starting again with a new harness, then obviously we'd keep it inside the cabin and directly into the ECU, but at this stage that would be really messy, hacking the Raychem boots around and then "orphaning" the part of the harness that runs to the engine bay. Plus, it gave us a backout plan should the BMW pedal not work out for us. (spoiler alert, it did) The leakdown numbers were exceptional (cold engine, obviously): Cyl 1 = 2% Cyl 2 = 1% Cyl 3 = 1% Cyl 4 = 2% Cyl 5 = 2% Cyl 6 = 1% Not sure which cylinder this is, either 2 or 3. https://hosting.photobucket.com/imag...720&fit=bounds Valve gaps were reset, and none of the headstuds required tightening. Inspection of cam lobes also done, with Matt also being very happy with them. We’re still waiting for the oil analysis to be formally returned; Opie Oils, who are doing the testing, ran out of consumables to do spectrum analysis on metal contents, and being Xmas period/Brexit/blah blah blah, we’re just waiting for that to complete. Informal feedback from them though, is that all other parameters are fine and nothing to worry about with the exception of the fuelling being a bit high….but we knew that anyway and was being worked on with the dyno session. With the installation of the Bosch 630cc injectors, the next job was to try firing it up and make any calibration changes that would enable Chris to drive the car back from Fearnsport to Northampton Motorsport. Encouragingly, it burst straight into life, no changes needed and idled just fine. Chris them remoted-in via Team Viewer to the Syvecs and pre-emtively made some fuelling changes in advance of travelling across to collect the car. At this stage we’ve got a clean bill of health and we’re all set to go onto the dyno up at Northampton Motorsport the following day..... |
Part 4 - D-Day….Dyno Time
We’re now the Wednesday before Christmas. Amanda and Troy at Northampton Motorsport had very kindly juggled things to get the car on the dyno for an afternoon slot before the festive break. An early morning departure from home to get up there in good time to again remove the rear bumper and prep the car for strapping down. The clients that had booked the dyno for the morning actually overran a little (they actually had a full day booking but *usually* only needed a few hours to systems check each new build car going on there). We didn’t get the car strapped down until about 15.30, so to say I was getting a little twitchy was an understatement. However, Troy had said that he was fully prepared to work late into the evening (now that his facility is ultra quiet and not upsetting neighbours). Fingers were cable-tied crossed that we’d have a straightforward session. The first thing I noticed when looking over Troys shoulder, was just how sensitive the new BMW eThrottle pedal is. Just resting your foot lightly on it, you can see a voltage change in SCal (Syvecs' mapping s/w). In retrospect it’s little wonder the old mechanical setup was feeling like it was disconnected; that same level of foot pressure wouldn’t have amounted to even taking up the cable slack, nevermind registering a reading in the calibration. The injectors dialled in very easily. In fact, it was all pretty uneventful. Drawing comparisons to the previous Injector Dynamics 1050’s, what we found previously was that the duty cycle on such a large injector was sub-optimal in the opinion of both Fearnsport and Northampton Motorsport. If memory serves it was about the 4-5% mark at the lowest end of their operating window, the suspicion being that very light throttle openings were being compromised with too much fuel delivery, even at this low duty cycle. But, what I would say in the balance of fairness is that we were also battling the throttle pedal. As with any well conducted scientific test, only change one thing at a time. In the real world, with limited time and (frankly) budget, we had to change both the injectors and pedal, see how it all performed and set it up as well as possible. Something that was manifesting itself was a driveability area at the 1700-2200 rpm range, with quite a significant stuttering when going from steady state and then applying light throttle, e.g., the amount of throttle you'd use in heavy traffic to keep pace, or when “politely” overtaking something. It’s actually something that bothered Troy more than it did me, I was more concerned with the ham-fisted and clumsy pulling away from a standstill. What Troy was finding was that he could make changes to cater for the light throttle issue but that would compromise heavier throttle loads, and vice-versa. I’m probably doing a very poor job of conveying what Troy and Alex were struggling with, I’m no calibration expert so please don’t go critiquing what I’m writing here, it’s merely a recollection rather than verbatim testimony. Would we have solved the issue just with a change of the throttle? Maybe, but doubtful. Collective thinking was that the midrange stutter wasn’t pedal related. Some years ago it was met with a healthy dose of scepticism that I had chosen a 1050cc injector. Not doubting that there are people like Scott Winders getting the results they're after, and I'm certainly not going to enter into a "debate" over it. There's an infinite amount of variables with these projects, different combinations of parts that WILL change how engine behaves, we all know this. These guys between them look after some immensely impressive and highly tuned toys for some very demanding customers…think 918's (not a typo), CGT's, F40 Evo's, all flavours of very pedigreed RSR's, ex Le Mans 993 GT Evos, 'Ring record holding 911's, etc... so I'm not about to second guess their experience and knowledge. They're the ones in the driving seat and calibrating this thing; if they felt that swapping the injectors would yield better results then I’m going along with it. What I will also say is that we're now at the top-end of the operating spectrum of the new Bosch injector, and on WOT we're probably beyond the comfortable duty cycle. You only find this by spending time (and money) on the dyno. Not a problem for us with a road car. Any more than a few seconds of using WOT and it gets silly on the UK roads. Very seriously, jail sentences are a serious consideration if you want to use more than a few seconds of WOT. If this was a track car, or pulling a 30 seconds at time of WOT down the Mulsanne, then we'd need to go for a half-way house option and reduce that duty cycle. But the Syvecs is far more tolerant (better injector drivers) than a lot of ECU's (e.g my previous MBE system which would've popped the drivers very easily). Finding out how these current injectors performed was all done 3 days before Xmas; literally no more time to start experimenting with injectors at this point, that's for another day. My personal thoughts are that a 750cc injector would be the Goldilocks option. Maybe with a future exhaust system change I’ll add a set of slightly larger injectors and see what happens. So…..did we actually eliminate that light throttle driveability stutter? I’d say it’s 90% gone. Is it something that bothers me? No. Lucy and I have now been out for a couple of long drives, mixed driving down some motorway, fast and (very) slow country lanes. It’s there still.....but if I didn’t point it out, you’d likely never notice. Once Troy knew what to look for after using the car as his daily, he spent a lot of dyno time refining the calibration. It did immediately feel better but not entirely gone. I briefly mentioned Alex above; I’d not met Alex before on my previous dyno sessions…no idea how, but there you go. Great guy, who Troy speaks extremely highly of. Young and sodding clever when it comes to calibration and creative ideas. Together they decided to focus (or refine?) PID techniques (Proportional Integral Derivative) to control that particular rev range tighter. Upping the Lambda sampling rate to sharpen up the fuelling. Again, not being a calibration guy, this was all starting to get way over my head. I understood the principles that Alex was telling me, but his propeller was clearly spinning hard, so I let them crack on and see what they could do. Results seemed to come thick and fast at this point, Troy and Alex looking far happier with things as the evening progressed. Next job was to do some full power runs. The Syvecs does have a very sensitive approach to knock detection, but with some fine tuning (teaching) and pushing the limits a little more than we did 2yrs (although still very safe) and adding a little more ignition timing, we netted a nice gain in both hp and torque, right across the rev range. Couple of videos to break the text up...you've seen similar before....note the smart new tiled floor, done as part of their refurb work...means we no longer need to use heatproof matting to protect the old painted floor from my screamer pipes! Apologies for the audio attenuation...was just quickly shot on the iPhone. Gives you an idea anyway. <iframe width="560" height="315" src="https://www.youtube.com/embed/hNiqfRaaUWQ" title="YouTube video player" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe> <iframe width="560" height="315" src="https://www.youtube.com/embed/1KXFErG5_Pk" title="YouTube video player" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe> As you can see below, the red line is from the last session back in 2019, the black was this session. Headline peak numbers are +12bhp and +18lb/ft, but better still is the midrange increases of about +26lb/ft at 3,000-4,000. Peak hp is now 538.1, and peak torque 516.4lb/ft. That should be "adequate" :D https://hosting.photobucket.com/imag...080&fit=bounds At this point it’s getting late and time to call it a day. Troy and Alex are happy with things, notwithstanding a real world test drive being satisfactory. A long drive home for me beckoned (in the M2C, not in the Porsche) with a plan to come back up the next day to do that test drive and all being well, to drive it home! |
Ha, I was wondering when we'd next hear from you Spen and here it is. I'll just say that your car stuff here is so other-worldly that I cannot draw any comparison to my cars. The photo's, however, are worthy of a Paul Raymond magazine. (True story, relevant only to aficionado's of English naughty mags ... i.e.. 99% of Englishmen: a guy I met through work in Connecticut is called Paul Raymond ... I was like, "Dude, great name!". He looked perplexed and sheepish, so I realized it was better not to explain it to him.)
On a more serious note, is it accurate to say that the BMW throttle e-pedal works better because the sensor is located on the pedal assembly, as opposed to via cable, and the slop that creates between the physical motion and the signal measurement? I was in London/Surrey in November, first time in two years, and the extent to which you now HAVE to drive within the speed limit (i.e., cameras everywhere), even on the M4 ... it blew me away. As in, it's finally been done, everyone brought fully to heel. And the arbitrariness of the congestion/"pollution" zone ... people having to sell their special cars based on which street they live on ... I suppose the future is here and it's absolutely 'orrible. Very glad to hear from you. John |
Hey John! Great to hear from you!
Lol at the Paul Raymond....hahaha, couldn't possibly say whether I know what you're on about or not....I wasn't in that Club, however am familiar with certain posh parts of London, but I did find that the places there were generally for men only. ;) ...aaaaanyway. Yep, bang-on with the BMW eThrottle pedal, no cable stretch, linkage slack or (maybe) slightly off leverage ratios, just a source signal straight to the ECU. Oh yes, there's now quite a few roads with point-to-point average speed cameras. I wouldn't say many non-motorways have them though, perhaps some dual carriageways or roads being worked on. There's still a lot of good driving and riding to be had, you just need to know where to find it. Truth be told, a lot of those uber controlled roads are generally head-to-toe traffic at the best of times, so there'd be little opportunity to drive "enthusiastically" anyway. |
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I am just surprised that the ID 1050x injectors did not work well for you. My application has only 369 HP at the wheels and I get great drivability and throttle response from the engine with them. I am using a MoTec M130 ECU and it has tables for the injectors which describe the flow characteristics at various voltages and fuel pressures. What's really cool is I could change to another injector and, as long I as MoTec has tables for those injectors, I wouldn't even have to retune. I could even change fuel pressure and not have to retune. At least in theory. All cool stuff, but, if they don't work for you, that doesn't matter! |
Part 5 – Car Collection & Thoughts So Far….
While still at the dyno on that evening of fine tuning, a hastily phonecall to good old Dad, seeing if he could quickly drive me back up to Northampton the following day. Thankfully he was available and willingly said yes. Good old Dad! It would’ve been possible to use the train to get up there, but I really wanted to spend the day with Dad, having a good old natter on the drive up there (about 3.5hrs on a flying run through), and after many years of keeping him abreast of how the project is going (and dealing with my frustration venting along the way), he’d never actually seen where all this was being done. An hour or so spent getting the rear bumper back on and it was time to test drive it around the local, busy roads. This was purely slow speed testing, making sure (for example) it didn't stall when pulling up to junctions or making sudden rapid stops. After quite a bit of fine tuning to things like the idle map engagement, it’s all good to go. The trick they put in place to deal with heavy voltage loading has worked a treat, it works like, er, a normal car. And….Oh. My. God. What a difference. That new pedal is just magic. No longer do I have to deftly dance the pedals like Walter Rohl to pull away from a standstill and not embarrass myself with either stalling or making a racket. It drives….normally. Pulling away is smooth, it doesn’t try and stall, it doesn’t get all lairy…it just “does”. In fact, at the moment, every drive I do I marvel at it. The simple things, eh? The drive home, with Dad tailing me, was just horrid. 4 hours of solid traffic. Dad really doesn’t like driving at night these days (the UK seems to have a policy of reducing light pollution and switching off many street lamps, leaving the only lighting that of oncoming traffic with modern ultra bright LED’s / Xenons). We had hoped to heading back home early afternoon before we lost the light. Nope. Didn’t happen. We had about 30mins of driving before sunset, the roads wet and filthy. In turn, I wanted to make sure Dad was in my rear view mirror, so for once I was the one being overtaken not the other way around. What all that meant, was that I spent a lot of time in that strange rev-range described previously….brushing the throttle to maintain the 50-60mph speeds we were limited to in the traffic (and point-to-point speed camera zones), and therefore transitioning right through 1800-2200 revs frequently. So, after arriving home, I did have to remind myself that this really isn’t the sort of driving the car will be used for; it was literally the polar opposite. Was that subtle stuttering noticeable? Every so slightly, yes, I’d be lying if I said it wasn’t. But it was a hell of a lot better than previously. Way different. Troy had previously said that he wondered whether this was due to intake tract wall-wetting, with the usual wide-angled spray patterns that suit modern multi-valve engines not being focussed enough for single valve heads. I guess the only way we’ll find out is to experiment at some time in the future, if/when we have genuine need to go back on the dyno. What does the increased power actually feel like? Terrifying! On that dry-road drive I confess to bottling it a couple of times once max boost was made. It was genuinely shocking, complete sensory overload, just like all hell had been let loose. A mate of mine had spun his BMW M2 the week before on those same roads (and smashed it up)….I didn’t want to be a second victim in as many weeks! The torque delivery is so strong and linear, it’s relentless. Sure, there are higher horsepowered projects out there but I really do think the balance of torque to power is spot-on and on these roads in good old Blighty, it feels sodding quick. Lucy was in the seat the other day when I went WOT….she’s grown up experiencing fast stuff with me, but even she gave an involuntary “Good God!” after being thrown into the back of the seat. The other Saturday we went on an afternoon drive out. My first time to really think about the suspension setup and how it felt. I can’t wait until the warmer weather. I stand by my initial thoughts from back in June; perfectly civilised when not pressing on, but when you are able to make progress, it just feels sublime. There’s a list of finishing jobs to be done now that I have it back; a few interior jobs, the transmission undertray was refitted the other day, the horn has stopped working for some reason (should be an easy one, prob just a loose connection after removing the steering wheel to extract the rev counter). |
Part 6 - Other jobs, fine tuning and drives out
The Christmas period over here was just rubbish in terms of weather. Wet, cold and slippery. Not the weather for being a hero but I did get the car out once for a quick spin during that time. Lucy and I have also been on a few days out, which has been great. Something I have noticed, and chatted over with Chris (at Northampton), is the throttle pedal actuation rate. This is all fully tuneable, but at present the boost targets at various opening %-ages feels just a little soft to me….the pedal feels quite long with the high boost targets being pushed out to high throttle positions. It kind of made the car un-energetic during normal driving. So, last week we scheduled a remote dial-in session to change these a little and also to show me how to do this myself, so I can tinker with the calibration self-sufficiently (dangerously, lol!). There are two areas that can be changed in the Syvecs SCal s/w; the Pedal Position Sensor (PPS) to Throttle Position Sensor (TPS) Target is one strategy, but not the one he recommended to play with at the moment. The more interesting one is the wastegate control strategy, which sets the manifold target pressures relative to the PPS and the gear. Comparing the current calibration profile against the one I'd been using up until December, they are both similar in terms of the shape of the graph (neither are linear), however the "old" profile had a boost target of 30% from 0 revs. The new profile started at 0% boost at 0 revs. This therefore meant a steeper ramp toward the higher rev range, hence the "all hell let loose" sensation. I've now reverted back to the old profile, and given it only a few shortish test drives. My first drive wasn't particularly successful for very different reasons....6 miles into the drive, minding my own business and in town traffic at 30mph, I went to accelerate and heard a very loud tractor. My tractor. "OMG, what just happened??!" A quick stop at the side of the road and it's very clearly exhaust related, but nothing looked to have fallen off. A bail-out route through the back streets, and a gentle limp back home followed by a cup of tea and a very quick inspection revealed....absolutely nothing that was obvious. No leaking head flanges, silencer is still bolted to turbo, no visible cracks in the manifolds. Oh no. Perhaps something more serious...or maybe a fracture within the heat exchangers? Slightly baffled, because the engine was barely up to temp, so no boost up until this point. Anyway, I got roped into Covid related hospital runs for the rest of the evening/night....left hoping it wasn't something catastrophic like a dropped valve. The following morning, early start, time to get the car on the lift for a proper inspection. Firing up the tractor, the noise seemed to be coming from the turbo area....was the housing cracked? Not that I could see, albeit with a heat shield hiding a lot of it. And then I saw it.....one of the blanked off Lambda sensor ports on the secondaries, that I had originally welded in there when intending on running 2x sensors. The one directly under the turbo compressor housing. A quick check with a piece of bent wire (it was too hot to use fingers) confirmed that it had made a bid for freedom but had left the ally compression washer in place. PHEW!....that's only a £5 and 5-day-wait problem to fix....unless..... At this point Dad appears with doughnuts in hand (hahaha) suggesting a coffee and chat. Good plan, was just regailing the story-so-far and he pondered the same thing as me...."Wonder if we can retrace our steps and find the blighter?" Coffee on hold, jumped in the car, we split up to speed the operation and 5 minutes later he called me to say he'd found it!....no bid for freedom today, Mr Lambda Bung.... https://hosting.photobucket.com/imag...080&fit=bounds Miraculously no threads were harmed in the making of this tale. A quick wire brushing later and it's back in place. Some fenaigling of tools to be able to tighten it (the first time I've ever been able to make use of these socket>ring spanner tools). A completely uninteresting story really, other than FOR ONCE the hunt for a lost part turned out to be successful. What are the chances.... https://hosting.photobucket.com/imag...080&fit=bounds https://hosting.photobucket.com/imag...080&fit=bounds https://hosting.photobucket.com/imag...080&fit=bounds And we'll try that test drive again, shall we?..... The car down at St Margarets Bay, near Dover. The "White Cliffs Of Dover" are in the distance in this shot.... https://hosting.photobucket.com/imag...080&fit=bounds ....and the white house in the distance at sea level used to be owned by Noel Coward (playwrite, actor, singer....Mr Bridger in the original Italian Job), who then sold it to his good friend Ian Flemming.... https://hosting.photobucket.com/imag...080&fit=bounds So, has the PPS>Boost map change made a difference? It does feel a little more hair-trigger, naturally. But with the new super smooth throttle pedal, this is far more manageable than it once was. However, it also feels significantly more energetic and lively...."spirited" even. With normal road speed driving, it now feels extremely responsive, with just a very gentle squeeze of the throttle to teleport you right up and close any gaps in traffic. It also means that the previous transition from normal/relaxed to full-send is far better. Not as violent or pronounced because you've been building more boost up until that point, but is nicer and more controllable, really using the strengths of the twin scroll turbo and its building of boost lower down. The profiles both have the same curve for all 5 gears, there really is no need that I can see (for the time being, at least) where we need to soften things in 1st and 2nd. Of course, if you go at it like a bull in a china shop, you'll break traction very easily, but appropriate driving presents no issues at all, even in this filthy weather. I may well have a play and build a graph that's a hybrid of both, just for the sake of playing and practising....we'll see. Chris and I did mull over that actually rather than having a multi-boost switch in the cockpit (which actually, we never change), it would be more useful to have that switch dial in different throttle characteristics, just like motorbikes do....they all deliver the same hp/torque, but in different ways. Unfortunately, it looks like my Syvecs S6+ can't do this, but the latest S7's can....but really, is it *that* useful? This is meant to be a fair-weather toy rather than a daily drive.... |
So, one of the perennial items on my "to-do" list has been to check out the ABS system. Not sure if this is common across other generations, but the 964 is known to have issues where because the ABS is never tested or used in anger, the actuators seize. First time you get to find out about this, is when you need to really stand on the brakes. Skid skid bang.
A number of years ago, a Rennlister called Michael aka "cajonfan" sat down and designed an ABS test unit for the 964 C2 (same system as used on the 964 Turbo). It uses an old ABS control unit housing into which he's build the test rig. It's brilliant, but it's been sat on my toolbox for 7 years now. I did exchange some PM's with him at the time, lovely guy and I know he was also working on a similar test rig for C4's, clearly a far more complex system with it's diffs and 4wd....but I've not kept abreast of what's available now, so if you are in the market for either, then maybe reach out to him over on that forum. Cajonfans 964 C2 ABS Tester Cajonfans 964 C4 ABS Tester thread Along with the test unit is a document with a full suite of tests to perform. The tests include things like checking the resistance of each ABS wheel sensor, simulation/activation of ABS scenarios, various voltage measurements to be taken under these conditions, and so on. Clearly you need to jack up each corner multiple times in order to check whether the valves are actuating and either locking the wheel or pumping and still allowing rotation. The one thing it doesn't do, is run a diagnostic against the ABS control unit itself. https://i.imgur.com/JmpFBLml.jpg?2 https://i.imgur.com/lqXKRSZl.jpg?1 https://i.imgur.com/R7yDQ4wl.jpg?2 (Photo's courtesy of cajonfan) Once I was underway, all 7 major tests (with their sub-tests) were done inside an hour. Thankfully my system passed each test with measurements that were spot-on in the middle of the anticipated ranges. I did note than on one particular corner, the valve seems to be reluctant and "sticky" to start with but after being exercised for a minute or so, it sounded like the other corners. If you did come across erroneous readings or malfunctioning sensors, there's also a full fault-tracing and diagnostic section in the documentation. I think I'll be adding this test routine to the annual servicing activities, knowing that the ABS can silently go AWOL. |
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How about a 2024 update on this one Spenny_b?
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I read mostly none of this and may be repititious, my 92 965 has Electromtive which is no longer in business, but all the systems have similar formats. I used the stock intercooler which is very proficient, 3.2 manifold, crank sensor, head temp sensor, map sensor, air intake sensor. Bob
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How about an update Spencer?
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