Hi all,

I am putting a 305 TPI an 700-R4 from a 1989 Camaro into my 82 Trans Am with a 165 ECM and I have a question about VSS. I've done lots of searching and I think I have an idea of what to do, but I need to check.

The 700-R4 uses a cable for the speedo and this connects to my car's speedo no problem. My car has the factory 1982 optical 2000 ppm VSS on the back of the speedo and from what I understand, all I need to do is connect the ECM wire from the speedo mounted VSS directly to the ECM and I don't need a buffer box of any kind. Right?

Do I need to change any parameters in the ECM? I read some people talking about changing a bit flag to change between optical and magnetic VSS or something but I can't for the life of me find a flag to do this in TunerPro RT. I'm using the AUJM bin and with the 6E XDF. Do I need some sort of hacked XDF file or something?

Any help would be appreciated.

 

For the 165 ECM, the output wire from the speedo buffer box (green?) goes directly to the ecm's VSS input. The optical/magnetic option only applies to the 730 ecm.

For the check engine light, you need to remove the buffer box that inverts the signal from the old CCC ecm, and directly connect the SES wire to the ecm (applies to 165 and 730 ecms).

 

Oh that is good news! That's one problem solved, easy as pie. Thanks also for the tip on the check engine light.

 

No problem. PM if you have more questions - I did a TPI intake swap to our 83 TransAM (LG4 non-CCC) about 3 months ago and most of the details are still fresh in the old memory bank.