I have a built trans with 3.29 gear but have never changed the trans tune. The speedometer is correct, and listed as a 3.29 in the speedo tab, so I'm guessing the reluctor wheel was replaced when built. Had a 3200 stall convertor, but it was toasted so it was replaced with a stock GTP convertor. Not sure what the old one was, just know that it was smaller in diameter and blue. Not sure if the flywheel is stock, heard of people using a GT flywheel for some reason!?! The problem is a vibration under throttle, and it seems to lock up quickly and bog down mostly in 4th, also takes quite a bit of throttle to unlock. If I am passing a car and hit the gas it will stay locked unless I hit about 1/2 throttle then unlock. All suspension parts have been replaced on the front end to rule that out on the vibration. So my question is, I've heard of people using a stock GT tune when switching to 3.29 gear. Do you think this would help/hurt my problem, and which tabs do I need to change if this could fix my problem? Sorry for the long post, just want to get as much info out there as I can...
Just an fyi...I was told what was in the speedo tab was correct because they changed the relucter wheel. Obviously I will take whatever advise you give since what they said is not working, just thought I would throw that info out there...
I get this error when trying to open, "Unable to open file. Index was outside the bounds of array". After searching I guess I need a newer version but it's not on my customer page. I'll email support. Thanks for the help, I will let you know how it works when I get everything in order!
Ok, everything up and running, tune flashed. Shifts feel a little weird at light throttle, 30% throttle or above feels pretty good. Didn't do a wot run. Also when the TC locks it's like it hits a wall, really kicks hard and kinda bogs down. Still seems like it takes quite a bit of throttle to get it to unlock, and my speedo is off by 5 mph. I really appreciate the help, I know nothing about transmissions!! I attached the file I flashed.
Gears were said to be a 1" 3.29 GM chain-set from the original trans owner, and the re-builder but I really have no clue. I have to go by what they say because I know nothing about them. I do know the install was pushed off a few days because they ordered a different relucter wheel, but not sure if that changes anything. The tire size I originally quoted is correct.
I am throwing a P0730 code now.
I attached the scan of 3rd gear. I have also attached the current file flashed to my PCM. I changed the MAF tables due to a throttle body and MAF install. Not sure if it makes a difference, but thought I would let you know.
Ok, at 2100 RPM in 3rd gear with a 3.29 drive ratio, you should be actually going 50 mph, not 55-56 mph as per your scan. Note that your calculated gear is .875, not 1.00
And I'm positive that you don't change the reluctor wheel when swapping sprockets. You need to reinstall the stock GTP reluctor wheel.
Might be worth trying to set the speedo tab the same as a GT to see if the calculated gear ratio is 1.00 & the P0730 code clears.
Ok, should I leave everything else you changed the same? If it helps at all, looks like it might be a 34 tooth reluctor wheel. ZZP sells them for gear set changes, but I did read somewhere that someone changed their 34 tooth back to the 30 tooth for easier tuning. Not sure if that changes your advise at all, I will try the GT speedo tables.
Update: So I changed to stock GT tables and my speedo was off by 10, GPS=65, HUD=75. The only way it is spot on right now is if the gear is set to 3.29 and the tire size is 23.00. 3rd gear was .984. I double checked my actual tires and they are 25.625. Is it possible with the reluctor wheel change the gear has to be set at 2.93 and my current tire size?
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