C6Antwon

I am swapping an LQ4 motor with a turbo into my IS300 and I have some gear ratio questions to ask. I am going to be using a 4L80 trans. Currently the car has 3.90 gears in it which won't work.

My choices are 3.07 or 3.42 gears to go with. I am also using a 26.5" tall tire. I want to drag race it sometimes but it will mostly be a street monster I'm leaning towards 3.07 simply because I've read turbo cars love the long gears.

Which gear would you go with and why?

DietCoke

iTrader: (18)

3.90s are best suited to the tall first gear on the 4l80, to be honest.

C6Antwon

Yes I know but I want it to trap higher than 118mph that's why I want to change the gearing. ANYONE ELSE?

atomic 6

Yes with that short of a tire, the 3.07 would be better with a turbo.


But how are you going to get a 3.07 gear for the rearend of the is300.

I didn't think that was an option.

DietCoke

iTrader: (18)

There's nothing wrong with shifting into OD on a 4l80. It isnt weak as most transmissions.

C6Antwon

Supra MKIII ring and pinion bolt right in

C6Antwon

Ok guys I can't use a 4l80 it's just too big. My question is if I get a 4l60, what year should I look for or are they all the same? Mind you the motor is an 07 6.0L.

Thanks