I am wanting to upgrade my 98 TA from the current 2.73's to either 3.23's or 3.42's, and can't make up my mind. I have a few questions.

What is the RPM's at 60 MPH with 3.42's in an LS1 A4 car?

What is the RPM's at 60 MPH with 3.23's in an LS1 A4 car?

Would the 3.23's be a pretty noticeable increase in performance?

Also..would it be ok to buy used GM gears, or would you guys go with new Motive's or something similar?

Would it be better to buy 3 series gears that will work with the 2 series carrier, or just buy regular 3 series gears, and shim or whatever. Sorry to sound so stupid, but honestly I don't know much about rear end internals.

Thanks in advance!

 

1753 rpm at 60 mph with 3.23 gears.

1856 rpm at 60 mph with 3.42 gears.

3.42 will be a bigger/more noticeable increase over 3.23, but both are an increase over 2.73.

Used gears are fine, but I would still buy new. Depends on the wear, and miles on the used unit.

Buy a gear made for 2 series carrier. If you shim it you need longer bolts, and the thread to gear contact is not as much.

 

why would you want gears for a 2 series carrier? I'd go ahead and buy 3.42's for a 3 series carrier. those are more common and easier to find a good posi unit for. 3.42's seem to be a well rounded gear for auto cars. a good stall makes all the difference.

 

He has a 2 series carrier, so he needs 2 series gears UNLESS he buys a 3 series carrier. See if you can't find a totaled out 6 speed and just swap the whole rear? Probally almost as cheap & less headaches setting the gears up.
Mike

 

I assume motive offers 3 series gears that will work with a 2 series carrier. I prefer to used Motives or GM gears. Richmond does, but I don't want to go with Richmond because a lot of ppl have complained that they are noisy. Maybe just a rumor??

 

You're honestly not going to notice the difference between the two, both are great with a good stall.