Can you just change the RPM for WOT shifts or do you have to change the MPH as well?


I've got the GM847 in my car and on my old tune the HP peaked at about 6600RPM, but on my new tune the car is shifting right around 6100. I am going to the track tonight and would like to change my shift points before then, and change them as/if needed at the track.


TIA,
Eddie

 

You will have to change the MPH if you have not modified the tables to shift by RPM only.

 

I haven't done anything like that, this is a tune that I got from Ion at MadZ28. To shift by RPM only is that the whole 1-2 @ 0mph 2-3 at 200mph thing?

 

Oh well, I just changed the shift points a little and am getting about another 250-300rpm out of each gear, I'll see how it goes at the track tonight and mess with them a little more there if I need to.

 

to shift by rpm lower your mph so it is met before the desired shift rpm is reached. you can do that using the kickdown tables. if you are dynoing the car and want to hold third gear then you can change the manual mode/up down shift table to have real high values. 2>3 can be set at like 255 mph and so can the 3>4 shift point. also don't forget to change your ecm constants table for the low PRNDL upshift and downshift speed threshold. you can set those at 255 as well.