It's known that when you swap a 749 ECM you loose functions for the EGR, CCP, and Air Injection because of the SyTy bin. I however want/need these functions to work being that I live in CA.

I've done all the searches and read every thread there is on this site about the 749. It seems to me that there are only 3 ways that I'm going to be able to make a bin that will do what I want. I can either:

A) Swap in a 749 ECM, re-pin the connector, use a V8 MEM-CAL with the SyTy bin, and install a 2 Bar MAP sensor. Then add the extra parameters for the EGR, CCP, and Air to the bin as I was told I can do.

B) Keep the 730 ECM, re-pin the harness as I would for a 749, use a V8 MEM-CAL with the SyTy bin, and install a 2 Bar MAP sensor. Then add the extra parameters for the EGR, CCP, and Air to the bin.

OR (this is my crazy idea)

C) Keep the 730 ECM, NOT re-pin the harness, use my current F-Body bin and V8 MEM-CAL, install the 2 Bar MAP sensor, and then add the extra parameters for running under boost that are in the SyTy bin into the F-Body bin.

It seems to me that if you could do option C I would get the best of everything, not having to swap ECM's, not having to re-pin, being able to operate under boost, AND have use of the EGR, CCP, and Air! I don't see why option C can't be done unless the re-pinning is required for the 2 Bar MAP sensor but from what I read here it simply puts out half the voltage per kpa right?

So is there any reason you could not do option C ??? I mean I'm no guru but members here told me that I could add the parameters for the EGR, CCP, and Air to the SyTy bin, then why can't you just add the boost parameters from the SyTy to the F-Body bin and then tune as needed for your needs?

Will this work or am I just crazy and misinformed?

 

Why do you loose all those functions?.
The Syclone has at least EGR and CCP, that I recall.

Unless you develope Source code, you'll only be limited to small patches.

 

Option C is A LOT more complex than you would think. It requires in depth knowledge of the 68HC11 and the assembly language used for it's programming. You'll also need to completely disassemble the AUJP, fully comment it, understand all routines that use MAP, and expand upon the VE tables. This project could take ... years.

Tim

 

This is do-able. Not real easy but do-able. You could start by studying the ANHT hac as it is very near to the f-body code.

There is one thing very different about the 8D code vs most (all?) of the other SD code: 8D uses ideal gas law to calc the BPW. The others use the simple VE * ~AFR * ~T * MAP * BPC to calc the BPW. This makes it difficult to study other boosted code.

All in all I'd love to see someone tackle this project and public domain it.

RBob.

 

Thanks, I'm glad to hear it is do-able but it looks like it would be a task WAY over my head. However like you said, it would be great it someone did do it and made the code available. Hell, I'd even help pay for some of the labor involved if anybody seriously wanted to tackle it for me. If it was done it would definantly be the hottest thing for all of us 3rd genners with forced induction. Heck I'd imagine the person who does it could charge for it to recover some of their time they put into and people would be more than happy to pay (I know I would for sure) as long as it's within reason like less than $100...

 

John Gwynne (sp?) actually started this project years ago. However, he never finished it. Somebody should still have the code that he started. As far as I can remember ... he modified the code to READ a 2-bar MAP sensor. But, that's all it did. It read the 2-bar MAP sensor and put the output into the ALDL stream. It didn't actually use the 2-bar sensor reading for any lookups or calculations.

Tim

 

Awesome, that code would be the perfect starting point! Just need to get ahold of it now. Is he a member on this board?

 

According to Rbob the EGR is wacky when the bin is switched to 8 cylinder. I havent chased it down but something in the calcs gives a bad number. His suggestion was just to disable the EGR.

AFAICT the SyTy and Sunbird don't show the CPP in the wiring diagrams.

Bob

 

How about option D. Who cares about if the EGR and CCP actually function? The smog tech has no way of knowing which ECM is in your car and if those things are being properly controlled. You don't need EGR to pass emmisions, and CCP has nothing to do with a yearly emmisions test.

But thats just me. I'm a fan of KISS

 

When the $58 code is set to an 8 cylinder the airflow calc always returns a value of zero. IIRC this only affects the use of the EGR.

RBob.