Crunch

Turbo 400 users:
What rear-gear ratio and tire size are you using??
Also, please indicate if you still drive your car on the street/highway.
I'm changing my setup to a TH400 this season, would like some input.
Thanks.

BIGBOS

I drove my car on the street all the time, took it to the track with my moser 12-bolt with 3.73's and a 3500 converter (non-locking), I spun around 3000 on the highway at like 60-65 on 27" QTP's.........I'm changing my converter to a 4000, and my tire is a 28" now......

For the street its an awesome tranny, especially with the manual valvebody, get a trans brake if you plan on racing it, that will help you a lot, trust me.......

Crunch

Yes mine has the transbrake, reverse manual valvebody. And I still have the 2-step. I'm using the B&M hammer shifter console with the T-handle with the T-brake button.

Reckless

iTrader: (9)

Mike Brown (9.85 car) has been running a TH400 with 28" tires at the track and 3.50 gears. He traps 138 with no problem. He also has traction issues from time to time

Hawkn01

iTrader: (1)

I'm getting ready to make a change to the turbo-400 with t-brake and a 4000 stall myself. I'm not sure which gear to run though. I currently have a 3.73 with a 26" tire and was thinking about a 4.11-4.30 with a 28-29" tire. Any suggestions or advise would be appericiated.

Crunch

Well, I would like to keep my highway RPM's as low as can be expected with a TH400. I think I'll try 3.42 rear gears, and 26" ET Drags.
My trap speed should be around 130MPH.

Pro Stock John

iTrader: (34)

28/10.5 slick + 4.11 when I had the 7.0 litre stroker + 4L60E

I have two gears at home, one is a 3.70 and the other is a 3.50, I think I am doing the 3.70 at this time.

smokinHawk

iTrader: (48)

well if i ever switch to the t400 id have to get my trap speed fast enough so i could use a low gear like 3.23s what would i have to trap 150's?

CHRISPY

With a big powered turbo car launching off a transbrake I wouldn't worry as much about rear gear if you are running a decent converter and still want to drive the car on the street.

The brake will allow you to launch off full boost and the optional 2.75 first will give you plenty out of the hole. I think a 3.42 combo with 28 inch DR's on the street and 26-27x10 inch slicks at the track would work very well and still allow you to get some semblance of gas mileage. I also think you wouldn't need to go quite as high on the stall as an NA car. Maybe 3000stall. Thw extra torque of the turbos really helps



Chris

Pro Stock John

iTrader: (34)

Seems like all the turbo LS1 and LT1 guys don't need a lot of gear and they peak ~6000 rpms... So I would start low and go from there.

Crunch

This is all good info!
I think I'll stick to my plan then: 3.42's, 26" ET Drags, 3200 stall, TH400 + T-Brake.
I can't wait to let her rip when the track opens!