I have modified my engine enough that the stock ecm doesnt run the car correctly. Rather than prom burning I am looking in to buying an aftermarket ecm. I was wondering which ecms would plug into my existing harrness because I dont want to have to replace it.

 

The prom is what needs "adjustment", the ecm just collects the data directs the information to the proper address in the prom and then sends the output signal to the appropriate hardware to make the physical adjustments.

 

Right..

And now to answer your question. The holley commander 950 works. A few other companies produce some aftermarket programmable ECM's that work with your stock wiring harness. I cannot remember offhand, so You'll have to do a search. I researched this a while back.. Expect to spend about 800.00 min..

-- Joe

 

The Holley will work good but won't plug into the stock harness.

 

Well it will, they sell this silly adapter.

-- Joe

 

here's what i sent holley:

I have an 89 tpi camaro with a modified engine (heads cam etc..) and I am running into problems with the stock comuter. I was wondering if the commander 950 ecu would work for my car and if it would just plug into the existing wiring harness or do I have to change it.

Thanks




and here's what i got: ?

Hello,
You do not plug into the factory computer, you will use the commander harness that comes in the kit. This will control the timing.
Thanks


Does holley sell the adaptor or does some one else?

 

You can go with.

DFI 6.32
DFI 7.0
F.A.S.T
Holley

all you need is a interface cable fasttrackperformance can help you out.....

The only plug and play unit i think is tha haltech E6GM but is getting old......

PS. I have exactly tha same problem!...dont have the money for s new ECM and dont have the stuff for
PROM burning.....

 

Come on guys....obtaining the prom burning equipment is not that exspensive ...I mean, if you're reading and posting on thirdgen.org it probably means you own a computer....that means you have half of what you need to burn proms anyway... Why spend just under $1000 for someone elses engine management system which will only allow you to adjust what THEY want you to have access to, when for around $200, the only limitation is how in depth YOU want to go? The factory piece can do anything the aftermarket can at a fraction of the cost...I'm not trying to say the aftermarket management systems are, in any way, inferior. They have their good points too... any way....it's your money....spend it the way you want to.

 

Hey,

Actually the the factory stuff we have is "ok" but its far from superior.

And I'm not saying the aftermarket stuff is much better, cuz if it was I'd be running it - not burning proms.

I kinda dig the LS1 setups though. But thats off topic.

-- Joe

 

Ya, them clowns at GM just spend millions ever year working on this stuff to make marginal equipment.
Shame they don't have the brains to save all that money....

The aftermarket stuff is just meant to be easy to work with. Half of them don't even allow for TCC management.

Actually other then possibly a few $5K ecms even can be mentioned in the same sentence as GM.

The trick is leaning what all you can do with the stockers.
There are hundreds of variables, and learning there interactions takes alot of effort.

 

I was looking into an aftermarket ECM unit, like the Holley Commander 950, but my concern is that I have an auto and the car is a regular traveler, so I also want to keep my cruise control. On their website, Holley states that the Commander does not manage cruise control or the torque converter lock-up. How would you guys piggyback the stock ecm to control just these two items and allow the Commander to do its thing?