When Well Enough Can't Be Left Alone; Backdate, EFI/ITB, AC, and more!

[Mixed76]

"I practiced my leathercraft on the strut brace for a clean bespoke look, just like everyone else."

Perfection

Sent from my Pixel 7 using Tapatalk

[Showdown]

Here’s the STL file for printing the desk clock housing:

https://www.dropbox.com/s/hb2ijgvjzx8gws7/clockHousing.stl?dl=0

[Showdown]

Well gents, as is the norm lately I haven't had much time with the car. That said, I did get to squander away part of Saturday to tinker with it inside and out.

The first order of business was to execute a wholly blasphemous procedure that will make knees weak: raising the car.

I have had my car quite low for a while and thus far almost all of my driving have been North of the City through the North Shore- communities with multimillion dollar homes and roads that cost just as much and are almost free of the defects and potholes that plague the rest of the city/state/country. Driving these roads with a very low car was wonderful; it tracked well, it was stuck to the road and it never bothered me.

Last week I took the car into the City proper and well, let's just say that for a rough ride like that some people pay houses of ill repute fine money. It was just brutal and wholly unsustainable and I wasn't even going all that fast. Given that I plan on actually driving the car on all roads this wouldn't cut it.

When I first tinkered with the suspension I swore that I'd never do it again, it was so brutal. I thought that replacing the bushings and installing adjustable spring plates would solve the problem but oh was I wrong.

Getting the spring plates out required all the swear words plus a few that I've now got on trademark, heat, and a goddamn crowbar. A CROWBAR. Fortunately I was able to get them out undamaged and reindex the torsion bars without issue. During the install process one of the threaded bosses for the bolts that hold the spring plate cover on stripped out. Ugh. So out came the dremel, angle grinder and welder to weld on a nut to the boss.

And just so it's known, I will be power washing the inner fenders soon...







Eventually after a few more hours than I had budgeted for the car was back together and raised a bit. I took it out for a quick drive on some gnarly roads and holy cow was it a revelation. It drove so much better, felt better, handled better and wasn't painfully rough. The change was totally worth it though at times I wondered what the hell was wrong with me for seeking out this punishment. It's never a Porsche project until something that you thought would require one wrench looks like this:



If I ever have to tinker with the suspension again though, I'll be converting to Rebel Racing solid bushings. That said, I'm pretty happy with where the car is sitting now and there's room to go up or down depending on my whimsy. I know it looks high but there's only about a finger width between the top of the tire and the bottom of the fender. It's not the look I would love to have but I want a car that drives good, not just looks good.



With the car driving so much better I then loaded up the laptop and went out to do some highway tuning, specifically leaning out the fuel at cruise. Driving up and down the highway with hand on the wheel and laptop pulling fuel out and reloading the tune is...interesting. Best performed on an empty highway or with a friend- neither of which I had so it was...interesting. Eventually I did get the tune leaned out and now a highway cruise I'm hovering around 17:1 without any backfires, missfires or stumbling. Hopefully this means I'll be a wee bit more fuel efficient on log drives than when the car was at 13.5 HA!

There's still work to be done on the scaling of the vertical axis but for now it's running so well that I'm a bit hesitant to change anything until I have a larger data set to analyze.



I have to say that now, being very comfortable with TunerStudio and my EFI system, it's a real pleasure to hear of feel something with the car and fire up the laptop and not only be able to see it in data, but fix it in a few minutes.

The skies saw me having a lot of fun and conspired to end my day early so back to the batcave I went to tinker with the interior.

After getting my new seats I wanted to return to the interior because in comparison it looked decidedly meh. My dash inserts are 2mm fiberglass sheets that are spot glued into the aluminum trim tray. When I made the first set I made a few spare sets of the inserts thus allowing me to change out the dash material in a matter of minutes. And so I did. The updated dash uses the same twill fabric as the seats and is angled to match the side vents. I like it, but if ever I don't and want to change it... 5 mins is all it will take.



While I had the dash apart, I replaced the hazard switch with an unmarked toggle, because I love unmarked toggles. I also turned an aluminum knob for the light switch; something a bit more...raw and homemade. I'm debating switching that with a toggle too but I have to do some reverse engineering of the light switch flow first.



I also removed the vinyl from the kneepad I made and wrapped it in the same leather as the seats. It's a subtle change but it makes a huge difference as you look at and touch it all the time. I think it was well worth the effort.



And finally I pulled the hidden USB port and replaced it with...a hidden USB port, this time with one that has USB-3 fast charging and USB-C fast charging so that I Can charge my laptop if I need. First world problems.



On the 13th I have a rallye (the first one was skipped due to a...blizzard) so I'll probably not chance anything on the car in the next two weeks. Plenty of smaller interior projects to play around with if I feel the urge.

[LJ851]

I wouldn’t feel comfortable running an air cooled engine at 17 to 1 AFRs…

[AG81]

Julian,

Really love the insert material and the toggle switches...... reminds me of one of Dad's old airplanes.

[chrisbalich]

Originally Posted by LJ851

I wouldn’t feel comfortable running an air cooled engine at 17 to 1 AFRs…

There are times when my car runs at 1.11-1.15 Lambda. (16.32-16.91AFR)
Cruising RPM with almost no load, there's no reason to pile on a bunch of fuel. Once any load is applied, the Lambda/AFR plummets back down into a 'safer' range.

This is the beauty of EFI. You can very specifically dial-in the calibration.


What I want to see is the timing map that goes with that VE map.

[PeteKz]

There is such a thing as too lean. Even though the car may not be missing or hesitating, at some point you start losing fuel efficiency. Unfortunately, determining that point requires a lot of dyno time and calibrated fuel flow, or a lot of experimenting over long distances on the highway with meticulous records. And it depends on the particular engine/vehilce combination, fuel type, and other factors. In the past, I understood that to be not much above lambda=1.1, but I've also heard that modern engines can run significantly leaner at better efficiency and without hesitating, so "it depends." But hey, have fun playing with it, and see what works best for you. I'd like to know what results you get.

[Showdown]

Originally Posted by AG81

Julian,
Really love the insert material and the toggle switches...... reminds me of one of Dad's old airplanes.

The car isn't a "theme" or "art" car but I am pulling a lot of cues from my time as a kid with my father at his airport where he flew hand-built sailplanes. It's a nod to him introducing me to the 911 and the fact that though he lusted after one his whole life he never owned one... The "euro" license plate I have is actually his tail number.

Originally Posted by LJ851

I wouldn’t feel comfortable running an air cooled engine at 17 to 1 AFRs…

Keep in mind that this is a stock 2.7 CIS car so it's already pretty fuel efficient and was built to be that way so running near 17 shouldn't be a big issue. If and when I change cams that will have to be addressed but that's for another day...

Originally Posted by chrisbalich

What I want to see is the timing map that goes with that VE map.

Stock 2.7 timing. I'm still running the dizzy. Jamie and I were talking about some options that may come in winter... muahahaha!!

[LJ851]

Obviously you can tune your car in whatever way makes you happy. An air cooled Ducati idling at 16.x to 1 AFRs will glow the headers cherry red for several inches off the head.

It would be interesting to monitor the cylinder head temperatures with those low load AFRs.

Love the build, thanks for sharing.

[911 tweaks]

stk 2.7 cis set up in this order: valve adj, ign timing, idle speed, ign timing, idle speed, fuel mixture @ f/d, set idle speed, adj mixture @ f/d, set idle speed, check ALL again after taking car for a rip...(afr of 13 - 13.8 using an exhaust co tester...)
Enjoy...

[Showdown]

Originally Posted by LJ851

An air cooled Ducati idling at 16.x to 1 AFRs will glow the headers cherry red for several inches off the head.

It would be interesting to monitor the cylinder head temperatures with those low load AFRs.

Love the build, thanks for sharing.

I'd say it's a good thing I'm not riding a Ducati, then!

~40 mins on the highway cruising at 16.7-17:1 and my oil temp was pegged at 190. My oil cooler fan wasn't on either. Ambient temp was low 60s and humidity was low.

Originally Posted by 911 tweaks

stk 2.7 cis set up in this order: valve adj, ign timing, idle speed, ign timing, idle speed, fuel mixture @ f/d, set idle speed, adj mixture @ f/d, set idle speed, check ALL again after taking car for a rip...(afr of 13 - 13.8 using an exhaust co tester...)
Enjoy...

I'm not sure you've followed along: stock 2.7 internals with an EFI ITB conversion; no more fuel distributor.

[911 tweaks]

Ok no prob… if efi itb… I would set up idle with afr no leaner than 14… same reasons still apply as this is still an old air kuhled engine…. Afr beyond idle speed & engine with load dependent on total build specs….JMHO

[eastbay]

Hey, I had to raise my car too. I could probably go 1 more spline on the back and a few more twists on the front yet. No shame

[nospiners]

I love those subtle interior changes !!! What's next with the engine ?? Pyrometers ?? It wouldn't surprise me ...

[pampadori]

17:1 at light throttle, low load was leaner than i could tune mine. It just wouldn't do it without missing. 15.3 was about it. And this required me to have about 40-45 degrees of advance.

Why do you think that raising the car a little bit helped with the ride so much? bump stops?

I've heard the race guys say that you have to trim some of the stops on the rear shocks if you got much below euro height.

[Showdown]

I hardly know a lot about suspensions but it seems to me that if one starts radically altering a stock suspension, it’s destined to perform with diminished results.

As my suspension is stock, the degree to which I lowered it coupled with the cruddy roads was just a combo too far.

I think to go that low I would need stiffer torsion bars or to start adapting the suspension as a whole system to accommodate that ride height and I’m not keen on that.

Whatever the reason, the return to a more reasonable height just makes the driving experience so much better. I guess they knew what they were doing back then!

[chrisbalich]

Originally Posted by Showdown

I hardly know a lot about suspensions but it seems to me that if one starts radically altering a stock suspension, it’s destined to perform with diminished results.

As my suspension is stock, the degree to which I lowered it coupled with the cruddy roads was just a combo too far.

I think to go that low I would need stiffer torsion bars or to start adapting the suspension as a whole system to accommodate that ride height and I’m not keen on that.

Whatever the reason, the return to a more reasonable height just makes the driving experience so much better. I guess they knew what they were doing back then!

Imagine if you had low-profile tires.
I can confirm that getting a quality ride at a low height is not the easiest thing to do. (I'm debating new shocks instead of the wide body I shouldn't do.)

[Showdown]

Originally Posted by chrisbalich

Imagine if you had low-profile tires.

I DID!! I had 50 series Dunlop Direzzas on 16" Fuchs. It was unbearable. I'll keep those for if I ever do a track day (hahaha!!) or when I just get sick of them collecting dust and want to sell them...

One of the reasons I'm weary of starting down the suspension rabbits hole is watching how much you've had to do to get the results you were looking for. While impressive, it's a cautionary tale for all but the bravest

[chrisbalich]

Originally Posted by Showdown

I DID!! I had 50 series Dunlop Direzzas on 16" Fuchs. It was unbearable. I'll keep those for if I ever do a track day (hahaha!!) or when I just get sick of them collecting dust and want to sell them...

One of the reasons I'm weary of starting down the suspension rabbits hole is watching how much you've had to do to get the results you were looking for. While impressive, it's a cautionary tale for all but the bravest

Don't tell anyone, but I'm not done yet.
Not by a long shot.

[rwest]

Originally Posted by Showdown

I hardly know a lot about suspensions but it seems to me that if one starts radically altering a stock suspension, it’s destined to perform with diminished results.

As my suspension is stock, the degree to which I lowered it coupled with the cruddy roads was just a combo too far.

I think to go that low I would need stiffer torsion bars or to start adapting the suspension as a whole system to accommodate that ride height and I’m not keen on that.

Whatever the reason, the return to a more reasonable height just makes the driving experience so much better. I guess they knew what they were doing back then!

Julian,

Lowered cars suck in the real world, good on you for raising it up to a reasonable level. When I bought my car it was fairly low and I got sick of literally picking my front license plate out the street when backing down slight inclines. When I redid my suspension, I raised it up to Euro height and am slightly tempted to go a tad higher.

Best,
Rutager