'96 ECM part number difference

[Bill H.]

Re: '96 ECM part number difference

I know a couple guys who have picked up used ones on ebay and they worked fine.

92-93 are much harder to find.

[Tyler T.]

Re: '96 ECM part number difference

Jim------


Apparently, the PRODUCTION part numbers for the 1996 LT1 and LT4 PCM's were different but the SERVICE part number for both was the same.

This implies that the difference between the two PRODUCTION units was slight, perhaps involving only something related to the assembly line test procedures.

The service replacement ECM would be the same but the calibration would be different so if you replaced the ecm it would need to be flashed with the correct calibration for the LT1 or Lt4. At the assembly plant they would have had the 2 different numbers so they were installed in the correct car. There are also 3rd party venders that will repair ecms.

Tyler

[Tyler T.]

Re: '96 ECM part number difference

On furthur thought NCRS cannot afford to let this just correct itsefl. The C-4 team leader needs to hold judging on this item until it is cleared up. If a judge advises the ecm is wrong and the member goes out and gets the 'correct' ecm he can damage the engine and may not have a car that will pass state emissions. On the production line these ecms have a number that denotes which engine it should be installed with, the black box will have a number that is the same for both applications but again each engine will have a defferent calibration. If you put an ecm with the calibration for a LT 4 in a LT 1 car the more aggresive spark curves and fueling could damage the engine conversly if you use the more conserive LT 1 ecm in the LT 4 you will loose HP. The calibration is like the carb on earlier engines and each engine pacage has its correct calibration.

Tyler

[Terry M.]

Re: '96 ECM part number difference

On furthur thought NCRS cannot afford to let this just correct itsefl. The C-4 team leader needs to hold judging on this item until it is cleared up. If a judge advises the ecm is wrong and the member goes out and gets the 'correct' ecm he can damage the engine and may not have a car that will pass state emissions. On the production line these ecms have a number that denotes which engine it should be installed with, the black box will have a number that is the same for both applications but again each engine will have a defferent calibration. If you put an ecm with the calibration for a LT 4 in a LT 1 car the more aggresive spark curves and fueling could damage the engine conversly if you use the more conserive LT 1 ecm in the LT 4 you will loose HP. The calibration is like the carb on earlier engines and each engine pacage has its correct calibration.

Tyler

Hey Tyler, why not drop an email to Allen Tremain and Tom Barr (contact info is on the contact page)

https://www.ncrs.org/contact.php

and tell them how to run the C4 judging. I am sure they will value your input.

[Ken A.]

Re: '96 ECM part number difference

[QUOTE=Bill Hetzel (53669);615620]I know a couple guys who have picked up used ones on ebay and they worked fine.

Not unless the vin # was flashed into the computer. The flash for an LT-1 is different than an LT-4. The computers for all 96's are the same, but the flash that is stored in GM's computer in the sky is unique for each vehicle. All vin's from 1994 to present are "on file".
In addition the files in each computer become corupted over time and an update is a good idea. The design of these early computers was poor in that the seals leak eventually and the GM expected service life was only 7 years.

[Tyler T.]

Re: '96 ECM part number difference

Hey Tyler, why not drop an email to Allen Tremain and Tom Barr (contact info is on the contact page)

https://www.ncrs.org/contact.php

and tell them how to run the C4 judging. I am sure they will value your input.

Terry ?????

The Lt-1 and Lt-4 discussion pertains to the 96s but the drivetrain specific calibration applies to auto vs 6 speed in any year. I have no desire to 'tell' Allen and Tom how to do thier job but it is important to those who are having thier C-4 judged understand just what the numbers on the ecm represent. I assume that both Allen and Tom are reading this thread and understand the importance of what these numbers mean. Calif does not care what the number on the ecm is but you will if you have the wrong ecm in place and fail emissions checks.

Tyler

[Jim T.]

Re: '96 ECM part number difference

Jim, does your label have the double bar codes like in Charlie's last pic?

Yes it does and I made an error on the numbers/letters, the first part should of read 86BSand not 8685.

[Jim T.]

Re: '96 ECM part number difference

Jim, agree with Pat. Do you have pictures?

The bottom of the label is sometimes removed. If yours is intact it will be twice the size of the one I posted.

Charlie I took a picture today using my wife's IPAD.

[Terry M.]

Re: '96 ECM part number difference

Terry ?????

The Lt-1 and Lt-4 discussion pertains to the 96s but the drivetrain specific calibration applies to auto vs 6 speed in any year. I have no desire to 'tell' Allen and Tom how to do thier job but it is important to those who are having thier C-4 judged understand just what the numbers on the ecm represent. I assume that both Allen and Tom are reading this thread and understand the importance of what these numbers mean. Calif does not care what the number on the ecm is but you will if you have the wrong ecm in place and fail emissions checks.

Tyler

Tyler,
I have struggled in judging a C4 at a chapter meet, and am looking forward to doing that again soon. I had occasion to spend some time with experienced C4 judges at both the Arizona Regional and the Northwest Regional, and while I learned a lot from them on both occasions I am no where near where I would want to be when faced with judging a C4 again.

I do know that both Allen and Tom are going way out of their way to train potential C4 judges because they want effective and accurate C4 judging all the way down to the chapter level. That will not happen soon enough, but at the same time it will not happen quickly. I do not believe we can assUme that they are reading this, although they may be. I will suggest again that you, and anyone else who finds what they think are errors or omissions in ANY judging manual, contact the appropriate National Team Leader. We can not assUme that they already know about the point under consideration nor can we assUme they are reading this unless they tell us so in a post. Having been a National Team Leader for over a decade I can assure you technical comments are welcome and the only way a change will be effected in a judging manual is if that suggestion comes to the attention of the Team Leader -- sometimes even more than once. Don't count on someone else to do it.

[Joe L.]

Re: '96 ECM part number difference

Tyler,
I have struggled in judging a C4 at a chapter meet, and am looking forward to doing that again soon. I had occasion to spend some time with experienced C4 judges at both the Arizona Regional and the Northwest Regional, and while I learned a lot from them on both occasions I am no where near where I would want to be when faced with judging a C4 again.

I do know that both Allen and Tom are going way out of their way to train potential C4 judges because they want effective and accurate C4 judging all the way down to the chapter level. That will not happen soon enough, but at the same time it will not happen quickly. I do not believe we can assUme that they are reading this, although they may be. I will suggest again that you, and anyone else who finds what they think are errors or omissions in ANY judging manual, contact the appropriate National Team Leader. We can not assUme that they already know about the point under consideration nor can we assUme they are reading this unless they tell us so in a post. Having been a National Team Leader for over a decade I can assure you technical comments are welcome and the only way a change will be effected in a judging manual is if that suggestion comes to the attention of the Team Leader -- sometimes even more than once. Don't count on someone else to do it.

Terry------


As I've said before, C4's are the most complex and high parts content Corvettes ever built (and that likely ever will be built) and will thus present judging challenges like no other Corvettes.

[Terry M.]

Re: '96 ECM part number difference

Terry------


As I've said before, C4's are the most complex and high parts content Corvettes ever built (and that likely ever will be built) and will thus present judging challenges like no other Corvettes.

Amen Brother!

[Jim S.]

Re: '96 ECM part number difference

In an attempt to add additional clarity to the question of what are correct ECM numbers for the 1996 LT-1, here is a pic from my 21k mile convertible. I believe it to be an unmolested car. Note, the service number is 16214399 (as mentioned by several others) and the detachable tab is still in place.

1996 ECM.jpg

Jim Simpson
1996 Arctic White/Torch Red Convertible

[Jim T.]

Re: '96 ECM part number difference

Pat my original owner 1996 LT4 has the following printed on the attachment to the ECM.

16230041 BSDF

Service Number 16214399

8685DFK260721794*

Error above, should be 86BS, not 8685