John..

To those of you out there who have tinkered...

What is your total timing advance on the boosted 944 engines, and at what boost level is this happening?

I am getting ready to fine tune my Turbo 928 and I am probably going to go with a total timing of about 18/22 degrees at 14 psig. Right now I run about 26 degrees on 8 psig without issue...I can even run 87 octane there if I want to.

My reason for asking here is the early 928 and 944 2 valve engines share the same combustion chamber design. The 944 setup should work just fine in my car. I will be running sans knock sensor, retard will be done with a pressure line off the manifold.

Any advice would be appreciated. Car has JE forged pistons and stock narrow fire ring Reinz gaskets.

Konstantin

sent me an email.

Konstantin

Russ Murphy

You've got mail.

Alan C.

At 20 psi I run 20 degrees with 50/50 110/93 octane. This is with a Tec3 and AF of 12.2

Alan C.

rage2

At 13psi I run 18 degrees with 91 octane fuel. SDS AF of 12.3.

At 20psi I run 23 degrees with 103 octane fuel. Timing slowly ramps down to 19 degrees at 28psi.

Turbo's a Huntley Stage 3 unit.

Sean Hall

Alan, Rage2, What compression ratio are you guys running?

Sean

John..

So, I should be safe with 18 to 20 degrees total advance between 12 and 14 psig at the manifold.

Thanks.

rage2

Bone stock compression.

fast951

John,

Start low on the timing and build up. Most 951 cars do have the knock sensor, and it does help control knock. Since you do not have knock sensor, some of the numbers listed here may not be what you should aim for.

Danno

Rage2's ignition timing looks scary to me... <img border="0" title="" alt="[Eek!]" src="eek.gif" />

Russ Murphy

Along these lines, Fast 951, what would you charge me to develop an ignition map for my SDS long distance?

fast951

Russ,

Developing a "good" ignition map is not something you want to do "long distance". Many variations will need to be accounted for. Also it's not financially smart as it ends up shewing up time. Beneficial for me as I bill hourly, but not beneficial for you.

Getting an "Ok" map is not a big deal. Getting a "good" map is more involved.

As much as I would like to assist you, I personally do not care for a just "ok" product, so it's not a project I would want to be involved in "long distance".

My best recommendation is to find a local tuner with a "Load" dyno that already knows SDS, and have them work with you. You'll end up with a good product without spending lots of $$$. I'll be glad to assist you on a limited basis, better to email me directly.

Did I just shoot myself in the foot?

crazyracer

John, I understand why Russ is asking you. Why don't you help him developing an ok map first and then let him decide. Maybe an ok MAP is all what he is after.

Russ Murphy

</font><blockquote><font size="1" face="Verdana,Tahoma,Helvetica">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Helvetica">Did I just shoot myself in the foot? </font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Helvetica">Heck no!
John,
I do have a local SDS tuner with a dyno (my buddy Booger-WRX tuner extrodinare) that has no 951 experience. So what I'm envisioning is paying you to provide a "base" map and then fine tuning it on the dyno and consulting with you about it on an hourly basis. How's that sound to you?
Russ

Alan C.

I have stock compression as well. I have gone up to 23 degrees but didn't find any big change. So I backed it off to 20.

I do have a nock sensor but I only moitor the nock. I do not have it set to adjust the advance. The engine is fairly noisey and you can see it on the plots.

I agree with fast951. Start low and work your way up. It's a lot cheaper!

Alan c.