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samgm2
August 4th, 2011, 12:58 PM
Off the methanol stuff for a while.

I have a couple of questions for those that have done it before. I am getting ready to do a conversion of a 1986 Corvette (C4) to the following: 2010 L92 with VVT and AFM (DOD). The original transmission in the Corvette was a 700R4. I've done a modification on my brothers C4 to a 4L60E in which I put in a bored and stroked LQ9 (to 427 cubic inch). This allows torque brace to work because the tail stock can be swapped pretty easily.

What TCM would be the best (a T42?) Does anything have to be done to marry the TCM to the ECM or is strictly CAN bus communication now? The older LS1 computers controlled both engine and transmission.
Does anyone know what number of OS I should look for to work with the E38 I am putting in? The OS of the E38 I am looking at is a 12625455. I believe that one supports both VVT and AFM. Any issues I should know about?

I put an LS6 into a Mazda Miata a few years ago and it is fine but as you might expect a bit over powered and can sometimes be a bit tough to control. I am looking forward to the vette modification and think can kill to birds with one stone since I can tune for Methanol! :-) It's all about the number of birds you can kill with one stone. A true Jedi can often kill more than 20 angry birds with just one stone...

Sam

Mr. P.
August 5th, 2011, 03:00 AM
...I've done a modification on my brothers C4 to a 4L60E in which I put in a bored and stroked LQ9 (to 427 cubic inch)...
Off topic -

Feedback please on the big crank in the LQ9, would you do it again? And what did you do to the 4L60, parts & tuning-wise, to make it live? Or did it?!

Mr. P. :)

ScarabEpic22
August 5th, 2011, 06:22 AM
Sam, since it sounds like you want to keep VVT and DOD/AFM active, you need to use either an E38 or E67 ECM paired with a T42 TCM. Are you going to use a 4L60/65/70E trans instead of the 700R4?

Do you have a throttle body, accelerator pedal, etc for the swap already? You probably know this, but the ECM year MUST match the tb and app otherwise it wont work correctly. If you're keeping a newer 4spd auto, GM never offered VVT and AFM/DOD paired with a 4spd to my knowledge (anyone else know?). Going to have a similar setup as 68problemchild then, might want to read his threads on the nightmare he has had getting the right ECM and TCM OSs to talk to each other.

http://forum.efilive.com/showthread.php?14596-First-drive-L92-with-VVT-and-4L70E-LOG
http://forum.efilive.com/showthread.php?16503-Shutting-down-torque-via-B2515
http://forum.efilive.com/showthread.php?16435-L92-4L70E-work-around
http://forum.efilive.com/showthread.php?16428-Torque-management-kicking-in-Posted-log.-Engine-backs-down-at-6000-rpm

Taz
August 5th, 2011, 06:57 AM
Hello Sam,

Erik was correct to point you toward 68problemchild (Patrick) threads - L92 with VVT (no AFM) paired with a 4L70. The ECM and TCM never really "liked" each other !

The only OEM pairing of a Gen IV V8 with an A4 (4L70) that featured both VVT and AFM - that I can think of - was the Sierra / Silverado equipped with the L76 (6.0 L).


Regards,
Taz

ScarabEpic22
August 5th, 2011, 11:05 AM
Ah brain fart, I thought the GMT900s had a combo like that, Id use a tune/pedal/tb from one of those trucks. Should save yourself lots of headaches down the road.