6L80E Hard Down auto Shift
Thread Starter
Racer
Joined: Dec 2019
Posts: 310
Likes: 41
From: Chicagoland
6L80E Hard Down auto Shift
2007 Corvette with a stock 6L80E.
Mods are an EForce making 7psi and headers. It has been dyno tuned.
It makes 430wtq at 3000rpm and
450 wtq at 3200rpm.
Since being tuned,
when Im cruising along around 35 to 45 mph in Drive and floor it it downshifts into passing gear as it should but it hits the lower gear/passing gear so hard it feels like something is gonna break.
This is with run flat tires so its not power going to the ground its the trans hitting hard, too GD hard.
A friend has the same car with same mods except his down shift does not hammer into passing gear. His down shifts smoothly.
My car up shifts on its own (not using paddles)in D and S fine.
Using paddles to down shift like for a roll race works fine.
Its just the automatic downshift, when in D under hard accel that hits too hard.
Any ideas on what this is?
This winter its going back to same shop for a fuel sys, flex fuel conv. and tune.
Thanks guys
Mods are an EForce making 7psi and headers. It has been dyno tuned.
It makes 430wtq at 3000rpm and
450 wtq at 3200rpm.
Since being tuned,
when Im cruising along around 35 to 45 mph in Drive and floor it it downshifts into passing gear as it should but it hits the lower gear/passing gear so hard it feels like something is gonna break.
This is with run flat tires so its not power going to the ground its the trans hitting hard, too GD hard.
A friend has the same car with same mods except his down shift does not hammer into passing gear. His down shifts smoothly.
My car up shifts on its own (not using paddles)in D and S fine.
Using paddles to down shift like for a roll race works fine.
Its just the automatic downshift, when in D under hard accel that hits too hard.
Any ideas on what this is?
This winter its going back to same shop for a fuel sys, flex fuel conv. and tune.
Thanks guys
Burning Brakes
Joined: Jun 2003
Posts: 846
Likes: 105
From: Knoxville TN
I wouldn't floor it and go WOT from a cruising speed or high gear as from what I've been told that is a good way to tear something up.
Either ease accelerator down gradually to get it to downshift a gear at a time or pull shifter in S and bump down with paddles and then floor it.
Either ease accelerator down gradually to get it to downshift a gear at a time or pull shifter in S and bump down with paddles and then floor it.
Supporting Vendor
Joined: Feb 2011
Posts: 3,523
Likes: 885
2024 C6 of the Year Finalist - Modified
2020 Corvette of the Year Finalist (track prepared)
2019 C6 of Year Winner (track prepared)
There is a LOT of torque management built into the tune whenever you try downshifting from 6-2 or even 5-1. That's why the car will actually feel quicker if you only lay into the throttle slightly instead of flooring it.
Although it can be tuned out I wouldn't recommend it.
Last edited by subfloor@centurytrans; Dec 1, 2020 at 11:44 AM.
