# Automatic Transmission - To answer the question about 4.10 with A4

performabuilt2
06-08-2008, 06:57 PM
dont do it, I have a stock 01 t/a other than tuning and 3000 stall went 13.1 on a 188 60 with 273s changed to 4.10s this week went 13.1 on a 191 60 and was on the limiter at roughly 1100 feet not a good combo with a stall IMHO maybe better with stock stall, RPMs on the highway running 75 3000 and used 1/2 tank in roughly 90 miles :chug:

SSkillz
06-08-2008, 07:31 PM
Did the 1/8 mile times change? I have a pt 4400 and got some 4:10's waiting to go in but I dont go to the 1/4 track most of the time its 1/8.

performabuilt2
06-08-2008, 07:38 PM
not really maybe 2 mph in the 8th I was redlining at around the 1000 and the motor just stopped pulling if you can turn it to 7gran or so and make power It may work for you but this was a real world test nothing changed but the gears and it didnt do anything for me

9000th01ss
06-08-2008, 08:30 PM
Before I make a change like that I do a simple math equation.
Say (for some odd reason) your shooting for mid 12's.
Whats a common MPH for Mid 12's, say 115 MPH.

Take rear gear x 355 x MPH / tire diameter = RPM at 1:1 final drive or rear gear x OD ratio if shifting into OD.

4.10 x 355 x 115 / 25.5 = 6564 rpm

If you want to lock the converter:
4.10 x 336 x 115 / 25.5 = 6212 rpm

If you want to go into OD:
4.10 x .7 x 355 x 115 / 25.5 = 4594 rpm

If you want to get some tall slicks:
4.10 x 355 x 115 / 28 = 5977 rpm

boola1341
06-08-2008, 08:52 PM
glad i didn't go with the 4.10's.

performabuilt2
06-08-2008, 09:00 PM
yeah I was only going into 3rd it dd shift into od one time after it bounced of the limiter