924Board.org

[Pascal924]

Hello,
I just bought a 123 ignition for my 1979 931.
There is a curve inside, but i was wondering of there is any experience here on the board with fine tuning of 123 system.

I have the intention to run the car with 0,85/0,9 bar turbo Boost.
This in combination with a orginigal gt Carrera intercooler and an s2 turbo.

Thanks for sharing experience or proven ignition curves.

[ideola]

No experience with 123, but this thread might be useful:
Reference Material on Programmable Ignition
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erstwhile owner of just about every 924 variant ever made

[Carrera RSR]

If it's a Mittelmotor dizzy then Michael at Mittelmotor should be able to provide some feedback on settings or at least offer the best curve. But still a rolling road tune should be performed to ensure its spot on for your car. My car is running a map provided by Michael with success.
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1980 931 - forged pistons, Piper cam, K27/26 3257 6.10 hybrid turbo, 951 FMIC, custom intake, Mittelmotor dizzy & cam pulley, H&S exhaust, GAZ Gold, Fuch'ed, Quaife
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[Pascal924]

Yes, iT is the same product.
I have seen your post with a picture of your curve.
I will compare this one and i am in touch with Michael as Well.
Did you do manny modificaties on the dyno?
Do you use the switch function between the two curves?
I want to make A switch in the dash....

This week an AFR Will be deliverd...and a manual boost controller.
Now i am still searching for A knock warning light.
I hear different story's About the reliability of those Warning lights

[Carrera RSR]

I haven't dyno'd since first install to check all was good, Michaels curve was good out the box, they appear to know what they are doing. Now I've developed some more and have installed further data logging sensors I do need to dyno again. I'm sure there is more to gain from the engine

I have a switch set up and have been using it recently with a 2* retarded curve above 4000rpm when pushing boost upto and over 1.2 bar using 100+RON fuel. I used a redundant console switch

I'm using a Zeitronix ZT-2 for AFR/EGT/Boost/pre and post IC temps. Also have a Phormula KS4 knock sensor. Had a few issues with interference which I have now pin pointed to a unscreened accessory cable. I was getting ghost det events which have now been resolved. I think most bad knock sensor results are from poor set ups. They will pick up other noise from the engine, not just knock.
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1980 931 - forged pistons, Piper cam, K27/26 3257 6.10 hybrid turbo, 951 FMIC, custom intake, Mittelmotor dizzy & cam pulley, H&S exhaust, GAZ Gold, Fuch'ed, Quaife
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[Dutch924-racer]

where did you put the knock sensor ?
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937 trackday car
Series 2 engine
951S turbo and intercooler
Fast road camshaft
Forge recirculation valve + boost controller

[Carrera RSR]

There's a spare boss on the block under the intake manifold. A little low down and away from source of ignition but at least it's far enough away from the head and the very noisy valves/cam folllowers
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1980 931 - forged pistons, Piper cam, K27/26 3257 6.10 hybrid turbo, 951 FMIC, custom intake, Mittelmotor dizzy & cam pulley, H&S exhaust, GAZ Gold, Fuch'ed, Quaife
Now www.924board.org/viewtopic.php?t=34690
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[Fasteddie313]

Sorry OT..
You are running 924 Carrera GT K26-2660GA/6.10 with the small (US S2/CGT) compressor at 1.2 bar? Thats a LOT LOT for that little compressor.. You mind sharing your pre and post IC IATs at full boost? I bet there silly high. No wonder you need to retard ignition and run 100 octane..

A bigger compressor and keeping that 6.10 turbine housing may help you out a LOT at high boost like that to keep IATs down, that has to be WAY out of the little 2660's efficiency range..
I'd recommend a compressor/cold side from a 951 /6 (cheap) or /8 (a bit bigger yet), or even k27 territory at those boost levels. Skip right over the 2664 compressor, that's not big enough yet..

That is crazy boost on that small compressor..
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80 Turbo - Slightly Modified

[WEASEL149]

Carrera RSR's post IC temps are cool.

Main risk with running beyond 1bar on standard turbo is knackering the thrust but he is well aware of that, and knowing him, it would just be an excuse for an upgraded turbo
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1979 UK 932

[Carrera RSR]

Post IC temps circa 6-10* over ambient on full boost despite seeing 100-120 pre IC. Don't plan on boosting more than 1.1-1.2bar. Ignition is 25deg on full boost usually. Usually 99RON pump fuel. Just trialled some octane additive to test limits of ignition and boost. All is good.

I was planning on using a 951S compressor on the last rebuild but was talked out of it as a modification too far too early in the build process. Hindsight is a wonderful thing and I should have gone with it. If I pop this turbo then it will be sorted during the rebuild.
_________________
1980 931 - forged pistons, Piper cam, K27/26 3257 6.10 hybrid turbo, 951 FMIC, custom intake, Mittelmotor dizzy & cam pulley, H&S exhaust, GAZ Gold, Fuch'ed, Quaife
Now www.924board.org/viewtopic.php?t=34690
Then www.924board.org/viewtopic.php?t=31252