Downshift issues

[someguy360]

Hi Guys.

I have had an issue develop in my VS for the last few weeks, wondering if anyone has any ideas.

Relevant info on the car: V6, Full exhaust, Tune, Corvette servo, 3.45 Diff.


What used to happen when I wanted to downshift is simply tap the accelerator, the car would drop down a gear and take off.....now I have to put my foot almost 3/4 of the way down before it even considers downshifting.


I have serviced the trans, checked the error codes (only had error 97 which is the charcoal canister solenoid which has been faulty for ages), checked and put a spare TPS on, cleaned MAF, checked for blockages in the intake and also checked the tension on the accelerator cable and still no luck.

Anyone got any ideas?

Only other thing I can thing of is that the car was tuned before the 3.45's went in, but it seemed ok for a little while

Thanks

[Brett_jjj]

The speed sensor ratio needs to be adjusted in the tune to suit the lower diff ratio, otherwise the auto wont shift correctly and the speedo will read wrong.. When I was doing tunes for people, I did a few for blokes who had a lower diff ratio, and when I tested the tunes in my car with the standard diff ratio, it stuffed up the shifts etc and it needed to be reved a lot harder to shift up or to kick down etc

[someguy360]

Thanks Brett

Have sent Steve from MACE a PM to see if he can alter the tune for me (tune was by MACE)

[Brett_jjj]

No worries, let us know how you go with it.