AndrewM

All,
Thought I would drop a line over here in case in might be of future use to someone, or maybe even now.
Had a Autronic EFI system installed in my 930 a while back. After having low rpm backfires, mid-range detonation, poor cold start and idle issues, I set out to find a good tuner for this system that lives here in the Midwest/East coast. Well, I found THE guy....not far away in Illinois at: www.speedlab1.com
It was well worth the 6 hr drive. After a half day on the dyno I had picked up 20 hp and the car runs razor sharp, all detonation gone, all backfiring gone.... I cannot say enough about Bob Payton and the work he did to get this car running right. Not only do they tune but they install also.
All the usual disclaimers....... I'm just one hell of a satisfied customer.
Hope this helps someone.
Drew
86 930

Auto_Werks 3.6

Drew, Thanks for this post and feedback. I just left Bob a voicemail to see if he can help me with a new project. I haven't found many places working with autronic, so this will at least give me some place to start.

AndrewM

No problem....glad to see the post has been useful!

Drew

jimculp

I bought my SM4 from Bob and he was great to work with. It was a difficult intallation (remotely) and he stayed with me through the rocky parts. He's a good guy.

I think he told me about your build a few weeks back Andrew. Sounded like you were making good power. I sent him a copy of my dyno sheet for reference.

So you have no exhaust popping in gear with no throttle?

AndrewM

Pretty much all gone, one will sneak by once in a long while.
I'll be going back in the spring to get an idle control valve installed. Might get the built in EBC system activated also....but I'm at .95 bar already and the boost builds pretty quickly already so I might pass ........maybe
Drew

jimculp

I don't know if I want to get rid of my popping

My AFR's are a 16 with trailing throttle, so I'm not sure how it's possible for me to still have popping. Anyway- great to hear you had a successful build.

m42racer

Is the Fuel system sequential or batch? Is the Ignition Wasted spark? Do you have a fuel cut when the engine goes into the vacuum? Very commonn for these engines to pop on the overrun if the fuel is still been injected and with wasted spark? If this is the case, you could have 20 :1 AFR, but the Cylinders that are on overlap and been fired with the waste spark will ignite the Fuel in the Exhaust. Measure the vacuum or see what the MAP is on your Fuel Map and then look to see if you are still injecting fuel. Vacuum means no or less air to mix with fuel. Lambda sensor if used measures Oxygen not fuel content.

jimculp

I should have said that I believe my AFR meter "peaks out" at 16:1- it's an AFX from NGK.

I haven't heard of sequential vs. batch fuel delivery- only sequential ignition. If I were to guess I have sequential with Autronic SM4. I run wasted spark. Thanks for the info.

nathanUK '81 930 G50

Jim, do you know if you have a cam sensor?

Stock EFI cars cut fuel by RPM (say above 1500RPM) and a switch on the throttle (when the throttle is shut).

jimculp

Mag sensor on the crank, hall sensor on the cam.

nathanUK '81 930 G50

You should have sequential fuelling then.

jimculp

Alrighty then.

bogey1

Dr. Drew, glad its running better. Having lived through it with you, and "in-line" for sooo long, I am glad you found someone to get it running properly. I wish he was closer to GA, maybe he could get mine running a little cleaner to pass emissions with a temporary program! does anyone think its possible to program the unit to pass an emission, then load the regular program back in?

AndrewM

I would ask him....I'ts really easy to switch programs, takes longer to hook up the cable to the ECU. LOL
I can't see why he couldn't write a "cleaner program" for emissions, since your stuck doing this on-line. Then back to the original program....BUT it might be worth the trip to go and get it done right.
Are you keeping her or it she still up for sale?

m42racer

Remember a rich condition can show up on Lambda sensors as lean. The popping could be a rich condition