964 3.3 Turbo EFI Conversion using Syvecs (Life Racing) Engine Management

[Spenny_b]

Originally Posted by jsveb

Spenny, I completely missed this. I am so sorry to learn this. You don't deserve such a situation. You have been so meticulous.

I really hope something great comes out of this.

Cheers matey, yeah, not good but I can take comfort in what I've discovered this evening....

[Spenny_b]

Ok, so I deliberately left things at a convenient place last night; the heads for 4-5-6 were off (still attached to the cam carrier) and I could see pretty much the full stroke of #4 bore, but decided to leave the cylinder removal until today.

BTW, using an engine crane to lift the cam carrier+heads assembly makes life a lot easier; the oil return tubes really grab the carrier casting, gently lifting it using the crane is a lot easier and less brutal than trying to heave it off. Just in case a newb is reading.

#5 cylinder was first to be removed, and it kind of set the tone for the other two on that bank....completely mullered rings....

#4 = all 3 rings smashed to pieces
#5 = top ring snapped in two places, and oil control ring smashed to pieces
#6 = top ring snapped

(for reference, the leak downs were #4=19%, #5=2%, #6=6%)

Thankfully, all 3 cylinders on this bank look to be good, no evidence of scoring and the integrity of the Nikasil plating looks fine. I'm not getting my hopes up just yet, they need to be measured before I'm happy.


Next, time to strip the 1-2-3 bank down and repeat the process. Better news...

#1 = Broken top ring (in 2 places), oil control ring not as badly damaged as #4, but still has chunks missing in 3 places
#2 = All rings are fine
#3 = All rings are fine

So, during the break between stripping each bank, Steve and I were chatting about what could cause such catastrophic failure of rings on the RH bank - he's never seen something this drastic.

For those who have been following the build for a while, you may remember that whilst on the engine dyno last year (in fact, exactly a year ago), we had a serious set of electrical problems, the most severe being that we lost the lower plugs on 4-5-6, plus the top plug on #6. Wrongly wired pin in one of the amp connections, plus another amp that was intermittent, which fixed itself "magically", and still seems fine now.

The best theory we have at the moment, is that this loss of ignition (and about 140bhp), caused excessive richness, detected by the Lambda but only at a global level across the whole engine. An auto correction was made, possibly causing it to run abnormally lean, and therefore hotter....the excessive unburnt fuel was at the same time washing the bores, removing oil obviously. With the increase in temperature, plus dry cylinders, it's plausible that the rings had massively increased friction, causing them to shatter.

The same cylinders that we had ignition problems with, are the same ones that havve utterly destroyed rings. What it doesn't explain is why #1 is also damaged.

Anyway, some horror shots for you, in no particular order apart from being 4-5-6...













And some fragments...(this is just #4!)



Short block and a bench full of parts...





And the expensive stuff...



Next job is to measure everything, which isn't likely to be this week as I need to get it all up to Steves and use the SBD shop Mitutoyo kit.

[Tippy]

That is seriously nauseating

[911 tweaks]

Spenny_b... I also have been following your build with great interest in doing such a build... after all of this time, effort,grief & expense, keep your chin up...! You are doing a fine job with what can happen when pushing the frontier on anything...!!! This will be conquered... hang in there... The second time is always at least 1/2 the time of the original build... carry on... Best of luck... Bob

[Spenny_b]

Originally Posted by Tippy

That is seriously nauseating

Yeah, I confess to feeling like I was going to throw-up a few weeks ago when all the evidence started to make sense. The same sensation you get on receipt of really bad news when your legs go to jelly. I did stop short of hyper-ventilating though, lol!

Originally Posted by 911 tweaks

Spenny_b... I also have been following your build with great interest in doing such a build... after all of this time, effort,grief & expense, keep your chin up...! You are doing a fine job with what can happen when pushing the frontier on anything...!!! This will be conquered... hang in there... The second time is always at least 1/2 the time of the original build... carry on... Best of luck... Bob

Thanks for the kind words Bob, for sure, we plough on and see what needs to be done....second time's always a better build anyway, haha!

[Costa P]

Spenny......im at a total loss for words!
Pain.....feeling such pain for you mate.

[304065]

Spencer: while I join the chorus of bemoans for the wasted parts and time, I am very impressed that you had the judgment to correctly diagnose and then immediately attack the problem. And you are rewarded with bits of shattered ring RIGHT where you expected.

Observation: A no-spark, fuel present condition shows as a LEAN condition to a wideband AF meter. The O2 sensor works by comparing the difference between the % oxygen in free air to the % oxygen measured in the exhaust gas. When the mixture is rich, the combustion event has consumed more O2 than stoch, hence there is less O2 in the exhaust. When it's lean, less O2 has reacted, so there is more present in the exhaust. If you lose the plugs then you end up with even MORE O2 in the mix, hence it shows as lean.

My money is on the ignition malfunction firing way early resulting in classic detonation. I don't see any erosion of the ring lands in your photos, but I'm looking at them on my mobile.

You are on the right track to mic everything up and that will make your next step perfectly clear.

Persevere! She shall howl again soon.

[Tippy]

Originally Posted by Spenny_b

Yeah, I confess to feeling like I was going to throw-up a few weeks ago when all the evidence started to make sense. The same sensation you get on receipt of really bad news when your legs go to jelly. I did stop short of hyper-ventilating though, lol!

Best wishes and speedy recovery!

I like the explanation above, makes sense as a possibility.

[fredT]

Sucky luck Spencer

I'm sure you will get it right, but this is gutting to hear nevertheless.

Makes me think I personally did the right thing with my shortcut to hotrodding, as as a checkbook mechanic this sort of stuff would would have cleaned out my wallet as well as my soul!

Hoping you'll get good wind and plain sailing going forward!

[Spenny_b]

Thanks for all your well-wishes guys, appreciated

Originally Posted by 304065

...My money is on the ignition malfunction firing way early resulting in classic detonation. I don't see any erosion of the ring lands in your photos, but I'm looking at them on my mobile.

Hmm, I'm not so sure...Dave the dyno operator was wearing the det-cans on every run that was made right up to the final run on the Friday evening (I seem to remember posting a photo of said Dave wearing said headphones!).

From what I understand, if we did have det, it would *likely* only shatter the top ring, it'd have to be monstrous to destroy the 2nd ring, but to bust all three? Steve's never known that, and I'm pretty sure from speaking with Chris, that he hasn't either (stand to be corrected though)....you'd also expect to see evidence of det on all 6 cylinders, but 2&3 are fine.

Originally Posted by 304065

You are on the right track to mic everything up and that will make your next step perfectly clear.

Was hoping to do this at lunch but stars didnt quite align - instead I've borrowed Steve/Craigs bore gauges and digi micrometer. Frankly I feel like death-warmed-up this evening, so it'll have to wait a few nights.

The planned way forward, before I disturb anything in terms of cleaning, is for me to try and book a days vacation and get up to Birmingham and speak directly with Fred @ Omega, see what his diagnosis is by examining the tell-tale markings (and see if he'll measure them on his rig, as I don't yet know the measuring points on these pistons, nor the original drawing dimensions)

Originally Posted by 304065

Persevere! She shall howl again soon.

Yeah, hoping. Fecking car.

[911 tweaks]

May I suggest as I bet you are going to do is examine the assembly tools used to get the pistons into the jugs AND to double check all of the measurements = jug dia and its wanted tolerance to piston & rings... I am leaning twds the rings getting damaged during piston/rings install and/or inaccurate tolerance btwn jug and piston & rings... The head phones would of clearly herd any pinging/knocking if it was happening... jmho... Also, depending on what compression you are running, now is the time to possibly alter that while the engine is apart...

[boosted79]

Ring end gaps?

[Raceboy]

If rings are broken, it is 99% sign of a detonation. If pistons are not melted, it means that detonation has not caused pre-ignition yet.

[Ken911]

Since you had detonation make sure the tops of the cyclinders are still round. Mine were not. When i sent them for replating i was told they were no longer round and should be replaced or cryo treated before they could be rebored and replated. I couldnt afford new ones so i had them cryotreated before they were rebored and replated.

[Spenny_b]

Time for an update

A trip up to see the 2 guys who own Omega in Halesowen (near Birmingham in the Midlands) was interesting, if not entirely successful in 100% diagnosis. This was over a month ago now, so bear with me while I try and remember the minutiae of the hour or so I spent there.

Long story short, this has stumped them both….I’ve stumped two guys who must be considered some of the leading authorities on piston design. Fantastic, if you’re going to do something, then *really* do it…

So, they can’t tell me the absolute root cause for the shattered rings. What they can tell me, categorically, are a few things that have NOT been the root cause….which you have to say, is almost as useful.

1 - First off, it’s definitely not detonation. No evidence of det on the piston edges, nor any deposits on the pistons that would usually accompany pre-det.

2 - Secondly, a theory that perhaps it could be related to some missing sparks whilst on the dyno (and perhaps bore wash) is also not the cause.

3 - Thirdly, there's no evidence of fretting on the ring ends, not even point contact, so incorrect ring gaps are extremely unlikely (especially since 2 cylinders are perfectly ok; that would have to be one helluva an unlikely tolerance stack-up to not see the problem on 2 of 6)

Other observations are:

1) That they don’t know exactly which rings these are….crazy as it sounds, they have the appearance of a steel ring but have the rigidity of a cast iron ring. The rings were supplied to me in a JE Pistons box (and dammit, I’ve had that empty box in my toolchest for 3yrs, until a few months ago when I had a clear-out). However, the packets with the rings were not sealed, and so they could’ve been any hokey old ring set, and knowing the outfit who supplied them, this is entirely plausible.

2) The chamfer on the inside edge of the compression rings is way bigger than they would ever spec, meaning it’s flexing significantly, perhaps excessively (for those who don’t know, this chamfer is used to allow the rings to behave a little like a window squeegie, exerting pressure onto the cylinder wall with piston motion)

3) The oil control ring should be flexible; Fred cited that their oil rings can literally be un-curled without snapping. At this point I start having 1980’s flashbacks and the ultra flexible material they made spectacles out of! When we got hold of one of my oil rings, it broke like a dry biscuit - very little elasticity, FAR too brittle.

4) There is a decent amount of scuffing on the piston skirts. More on the pistons with broken rings.

(As an aside, it’s at this point that Fred and Benk explain the intricacies of piston design, with not only a tapering of the skirt, but also an asymmetrical barreling between the bottom ring land and the bottom of the piston, in addition to the oval nature (in plan view) of the skirt. Some very big radii, think approx 1m in places.)

This scuffing has likely been caused by the lack of control of the piston in the upward stroke, by virtue of the rings being destroyed, causing excessive rocking. Still usable, but….

…when Chris and I then had a very long chat over FaceTime shortly afterwards, it appears that the diameter of the skirt is smaller than a brand new 98mm CP Carillo item that Chris had to hand in the shop. This starts to add up….the set of pistons I bought were the last of a batch run commissioned by [he who I’ll not name again] ….the old knackered pistons that [said person] tried to offload onto me were out of his 935 replica endurance race car….so, chances are, these pistons were of the same batch intended to spend many hours at WOT and running massive boost….and heat. Not a good candidate for a road piston, of course.

Which is disappointing.

So, the first item on the shopping list is a set of CP Carillo pistons. Chris and I have discussed at length, the ball is in my court to obtain some dimensions and send them over, so that a set of designs can be finalised which maintain the same compression ratio as we’ve dyno’d and mapped with. The engine is going to need re-dyno’ing again anyway, in order to perform a controlled running-in, but this is likely to only need 2 days dyno time - Day 1 to bolt it to the rig and fire it up, Day 2 to do some mapping, double check and refine. If we go radically altering the CR by more than 0.1:1, it’s really a case of all-bets-off and start again. No thanks.

The next thing to check were the cylinders. Steve & Craig very kindly lent me their Mitutoyo bore gauge set and the relevant digital micrometer….conscious that John is reading …so I made sure that everything was stored in the cooler confines of the garage for a day before measuring, lol!

Each barrel was measured both per the diagrams in Waynes book, but also per the Porsche factory manuals, plus in an area below where the rings travel at the bottom of the spigot. X & Y directions of course, I spent a good couple of hours doing this myself, noting, checking, re-checking, because frankly, I was aghast with some of the dimensions I was seeing. Time to make a journey up to SBD and ask Craig to mark-my-homework. In fact, we repeated the measurements, him measuring, me scribing. Sure enough, give or take the minute differences due to measuring locations, the dimensions were very similar to mine. Bugger. They’re well-worn; in fact, Chris commented that he’s not seen a set of cylinders this worn since stripping a race motor after 5 seasons of hard use. The good news is that they should be fixable.

The plan of action is for me to ship the cylinders back to Chris for him to get them stripped, re-plated and honed to the same spec as they would’ve left LN with originally. The pistons will be ordered, with the relevant rings (this time we'll be using 1mm not 1.5mm per the Omegas, which were designed for JE rings). Chris or Mike will then gap the rings, check everything, and assemble the pistons into the cylinders for a trial fit. New Wrightwood gaskets are going to be used for the re-assembly.

Realistically I’m planning on this all now happening towards the backend of summer, for an autumn rebuild. Feeling more than a little broke at the moment, need to sell some tin to get some commission payments! Mind you, it’s not helped by me having a mad-moment a few weeks ago and buying a new daily driver….F10 LCI generation M5….has to be one of the performance bargains of the moment (in the UK at least), unbelievable amount of car and performance for the money, I’d highly recommend. A complete weapon of a chariot that’s still scaring the crap out of me. Never owned a V8 before, so another box ticked. I’ll chuck up a pic of it at some point - for some reason Photobucket isn’t playing nicely, not allowing me to upload any content.

So that’s where we’re up to….trying to retrieve an errant wrist pin spring that (sods law) managed to ping its way into the crankcase. Have had a couple of attempts to see it (bore scope) and fish for it (magnets of different types), with no success yet. Fingers crossed I don’t end up stripping the bottom end for one bloody clip.

[Brainz]

Very sorry to hear, but sounds like you've got a great plan. As always, thanks much for posting your experience - - very educational. Look forward to hearing your progress later this year.

Side note, I watched the Speed Academy 930 series on YouTube (a couple times, actually) . Chris and the team at TurboKraft are truly top-notch, and nice guys to boot. I've been really impressed with the help they've provided you and others on this forum. So professional. Best wishes.

Sent from my Nexus 6 using Tapatalk

[Spenny_b]

Originally Posted by Brainz

Very sorry to hear, but sounds like you've got a great plan. As always, thanks much for posting your experience - - very educational. Look forward to hearing your progress later this year.

No worries, and thanks for the encouragement!

Originally Posted by Brainz

Side note, I watched the Speed Academy 930 series on YouTube (a couple times, actually) . Chris and the team at TurboKraft are truly top-notch, and nice guys to boot. I've been really impressed with the help they've provided you and others on this forum. So professional. Best wishes.

I've said it before, along with many others; Chris is an absolute top bloke, and somebody who I very much regard as a friend.

I've only spoken briefly to Mike once, a long time ago, and not spoken with John, but with their diligence and talent, I imagine that they're also great guys to have in the TurboKraft speed-shop.

(I've also watched a number of the Speed Academy videos, very good they are too)

[Pat RUFBTR]

Hello Spencer,
I have unfortunately just discovered your driving problem, I am great disgusted for you, stand firm and especially do not discourage you! We are with you.

Patrice

[fredT]

Hey Spencer how's it going?

What is going on with this?

Cheers

[Spenny_b]

Hey Fred,

Well, we're underway again, have been for some months although most of that time has been spent investigating, planning, cleaning....saving....

The cylinders are now back with LN via Chris at TurboKraft, to be reworked in readiness for a set of CP Carrillo pistons. Chris is going to handle this part once he has the cylinders back.

In parallel, I've been focussing on the ignition system - trying something which I don't believe anyone else has yet experimented with...a real case of "why not, whilst I'm at it". A fair amount of extra work needed, but I'll reveal all, once it's complete.

The 12x Denso (Honda CBR600) pencil coils are going to be up for sale very soon, as-are the 4x 3-channel Bosch amplifier units that drive them....if anyone's interested, then do send me a PM. All immaculate condition as you'd expect after only 3 days actively running on the dyno and 300 road miles afterwards.

The engine half of the wiring loom is back with Simon @ Sileck for reworking, or rather, in anticipation of me giving him the nod that my experimental project is good, then he'll start the rework.

Did have half a thought to also look at swapping in some new cams - again, while I'm at it....but frankly the budget just isn't there, and after discussing with Chris at length, the 964 Carrera cams should still be absolutely fine for what I need.

That's about it really. Will post some pics once there's stuff worth photographing, but yup, it's underway again, thanks for checking in!

Cheers
S