Changing gears in my 4T45-E....questions.

[mfuller]

mfuller, what do you have your gear ratio set as? 3.91 or 3.29. when i changed the gears in the 06 malibu, i went from a 3.69 to a 3.42. but i had to put the gear ratio at 3.05 because that is the differential i was using, and i noticed stock it had 3.29 instead of 3.69. when i put it to 3.42 like i though, it messed everything up. 3.05 is right on. its strange. i used HP tuners for that one though. i have tried to dial in trans settings with DHP PT, but its not as user friendly, and they use different tables from the comp for some reason. im going to try HPT when i get my grand am back up and running tho. and prob the DHP PT also. i like HPT trans tables better

I still use the stock 3.05 differential, so the new 33/37 drive/driven gears are supposed to yield a FDR of 3.42.
I used the DHP PowrTuner.
Under the Gear Ratio section:
Calculated Pulses per Revolution - 37.08 (stock is 35)
Pulses per mile - 24964 (stock is 25080)
Drive Sprocket Ratio - .89 (stock is 1)

I plan to tweak it further using both the PowrTuner and HPTuners, once the new motor goes in (with the 1280 cam).

[gectek]

yah...i use HPT so much, i forget how DHP is...lol. ill have to look at my config files to see what i have. maybe thats why i have problems, because i did not change anything but gear ratio

im running the 3.29 diff with 38/32 gears...giving a 3.91 ratio...all gear heh