Stall tuning required?
I put a 2800 stall in my Nova and it would not up shift with my foot to the floor, it would run up on the rev limiter and not shift until I lifted a little. Factory tune bases shift on vehicle speed not rpm, the stall converter throws this out of whack.1-2 shift and 2-3 shift never had my foot to the floor long enough to get a WOT 3-4 shift 
Thread Starter
Staging Lane
Joined: Jul 2016
Posts: 61
Likes: 0
I put a 2800 stall in my Nova and it would not up shift with my foot to the floor, it would run up on the rev limiter and not shift until I lifted a little. Factory tune bases shift on vehicle speed not rpm, the stall converter throws this out of whack.1-2 shift and 2-3 shift never had my foot to the floor long enough to get a WOT 3-4 shift
I put a 2800 stall in my Nova and it would not up shift with my foot to the floor, it would run up on the rev limiter and not shift until I lifted a little. Factory tune bases shift on vehicle speed not rpm, the stall converter throws this out of whack.1-2 shift and 2-3 shift never had my foot to the floor long enough to get a WOT 3-4 shift
This is incorrect.
Whenever the pcm goes into WOT mode it shifts based on RPM. Part throttle shifts are done by MPH. I have tuned 10+ vehicles and never touch the WOT MPH shift table. I only adjust the WOT shift RPM table.
You shouldn't need any tuning unless you get a slip code. Its kinda a toss up. I have only had one vehicle do it and it was my personal car. I do like to adjust the part throttle shifts with a big stall but its not required.
This is incorrect.
Whenever the pcm goes into WOT mode it shifts based on RPM. Part throttle shifts are done by MPH. I have tuned 10+ vehicles and never touch the WOT MPH shift table. I only adjust the WOT shift RPM table.
You shouldn't need any tuning unless you get a slip code. Its kinda a toss up. I have only had one vehicle do it and it was my personal car. I do like to adjust the part throttle shifts with a big stall but its not required.
Whenever the pcm goes into WOT mode it shifts based on RPM. Part throttle shifts are done by MPH. I have tuned 10+ vehicles and never touch the WOT MPH shift table. I only adjust the WOT shift RPM table.
You shouldn't need any tuning unless you get a slip code. Its kinda a toss up. I have only had one vehicle do it and it was my personal car. I do like to adjust the part throttle shifts with a big stall but its not required.
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Sorry, but this isn't correct.
WOT shifting uses both MPH and RPM in an AND statement for shift logic. Both inputs must be equal or greater than reference for a shift to occur.
A good way to correctly tune shifts is to make a MPH x RPM spreadsheet in excel using your gear, tire heights, transportation ratios and observed convertor slip. I set the RPM about 200 lower than desired and MPH 1 or 2 lower than what the spreadsheet tells me. Then I can micro manage it from there.
The reason I do it this way is that MPH has less number resolution and therefore updates slower than RPM. On a high HP car with gears, RPM moves quickly! I find it easier to get exactly the desired shift RPM by working backwards and using all the tables available.
WOT shifting uses both MPH and RPM in an AND statement for shift logic. Both inputs must be equal or greater than reference for a shift to occur.
A good way to correctly tune shifts is to make a MPH x RPM spreadsheet in excel using your gear, tire heights, transportation ratios and observed convertor slip. I set the RPM about 200 lower than desired and MPH 1 or 2 lower than what the spreadsheet tells me. Then I can micro manage it from there.
The reason I do it this way is that MPH has less number resolution and therefore updates slower than RPM. On a high HP car with gears, RPM moves quickly! I find it easier to get exactly the desired shift RPM by working backwards and using all the tables available.
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Verdad Gallardo I do it every time I tune a vehicle. I have never touched the MPH table. Just last week I had the trans freshened up in my car because it wouldn't make the 2-3 shift above 6400 rpm. Turned it down to 6 till i got it fixed and then turned it back up to 7K. I dont see how I can get lucky on 10+ vehicles.
I do it every time I tune a vehicle. I have never touched the MPH table. Just last week I had the trans freshened up in my car because it wouldn't make the 2-3 shift above 6400 rpm. Turned it down to 6 till i got it fixed and then turned it back up to 7K. I dont see how I can get lucky on 10+ vehicles.
I like to match the tables, then adjust the mph shift to be lower than the rpm. This way, if there is any trans slip, the rpm will cause an upshift. If the mph is higher, you could burn a clutch completely out instead of having enough left to limp home. I would be more worried about properly matching the part throttle stuff with a stall, since the factory settings are low enough to build a lot of extra heat with much of any higher stall rpm. I suppose it is always worth repeating that an extra trans cooler is never a bad idea with a higher stall.
Thread Starter
Staging Lane
Joined: Jul 2016
Posts: 61
Likes: 0
I like to match the tables, then adjust the mph shift to be lower than the rpm. This way, if there is any trans slip, the rpm will cause an upshift. If the mph is higher, you could burn a clutch completely out instead of having enough left to limp home. I would be more worried about properly matching the part throttle stuff with a stall, since the factory settings are low enough to build a lot of extra heat with much of any higher stall rpm. I suppose it is always worth repeating that an extra trans cooler is never a bad idea with a higher stall.