CT Downshift times in normal special and select

[el es tu]

What would be a safe amount to lower these values and get a noticeable improvement (6l80 corvette)? I know with upshifts it needs to stay over .2 but I wasnt sure if the downshifts needed to stay significantly higher...

Thanks!

[topher455]

Actually the downshifts can have much shorter times than the upshifts. Start by removing about 25% then go drive it and see what you think. IIRC some of the sport downshifts on some stock cal's are 0.00 Also CT downshifts would be tought to really hurt anything since the engine speed and load are so low. HTH

[bluegoat06]

They're close throttle downshift times, just leave them stock, if you lower them too much, the CT downshifts would make the car feel jerky/clunky during CT downshifts when you're on decel or coming to a stop. There is no need to lower the times on everything you see, I have base times set at .19ms in my GT, but I use the shift inertia/torque adder tables to add some spice to the shift based on requested torque, the car feels stock at low throttle input, but the shift times are decreased at higher inertia profiles. The reason you see some cals with base times set to zero is because GM uses shift inertia adders/ torque profile adders and other tables, to model the shift time and shift feel. There is no need to mimic those base shift times , if your car didn't come with those values set to zero, the base times are just that, the difference in year models and calibrations was in the shift inertia adders/ torque adders etc, etc. if you set the times to zero (if your car didn't have the base shift times set to zero), the car would shift like crap because the other modifiers are not set correctly. With this transmissions, try to keep it simple, and you'll do more with less , it's easier to understand how it works if you take the time to modify the tables slowly and keep the changes simple and small. you wouldn't believe the difference .05ms would do as opposed to .30ms in the base shift time table. If you remove too much from the base shift time, the shift would become jerky and shitty.

Have fun.

[topher455]

True. I have some time removed from mine just because I raised my part throttle shift mph a bit for a more sporty feel when driving. Esp when slowing down at closed and light throttle to get the downshifting and engine braking that many sports cars have. So I had to firm mine up. I control my G8 much much differently than the factory originally did though. It is the result of about 8 months of development and Im very pleased with it.

To the OP Blue is 100% correct though. Even .02 in a shift time table can make a world of change. This is a fine adjustment type deal. Large coarse changes will give you nightmares!!