im trying to put a 450 hp motor in my car its a 91 rs im wandering if im going to have to get a different transmission for the power or rebiuld this one or something. its got the 5 speed manual?

 

Stock T5 will not live behind 450 hp. I used to have a link to a company that beefed T5s to take big power, but I can't find it. Might check in the drivetrain section. You could also go with a T56 swap.

 

I take out T5's with my 305,l
but I've heard of guys running 383's on a T5

hp isn't the problem it's torque that'll kill it,

450 is alot of hp, what combo are you running

 

g-force transmissions sell upgrade kits for the t-5
the stock t-5 is supposedly rated at 300 ft-lbs of torque

if you are making 450 hp on a chevy small block, then you are definately putting out over 300 ft-lbs of torque

easier than getting the stock t-5 rebuilt with the g-force upgrade kit, is switching to a t56 transmission, which can handle somewhere around 450-500 ft lbs of torque

 

http://cgi.ebay.com/ebaymotors/NEW-G...00377907QQrdZ1

is that what i need?
and do i need to do anything else to my driveline?
and where can i get this t-5 upgrade kit seems it would be easier to just upgrade the one i have?

 

http://www.g-forcetransmissions.com/tran_gt-5.asp

 

The one on e-bay would not hold up. Its in the ad that it is good for only 400lb/ft torque. I have a motor with 430lb/ft and 425HP. So your motor with 450HP should certainly have 450lb/ft. I upgraded to a Punisher 700R auto that is good for 500HP from
http://www.maddog-transmissions.com

 

You know, just because a transmission is rated for 300 or 400 or 500 torque, its not going to blow up if you have 1 more than that rating. The rating is a general idea based on the relative strength of the transmission, as judged by the manufacturer. Also keep in mind, the rating is based on street tires and a stock clutch. Put sticky tires and a performance clutch in there, and the rating of the trans goes down considerably.
My stock T5 lasted thru 3 years of 400+ ft/lbs of torque at the wheels, with ET Streets and a McLeod clutch. Until I started running 12's. Then it broke on the next pass. My T56 has lasted thru the same abuse for another three years with no problems. Your results may vary.

 

put a turbo 350 in there, best move i ever made. my car had a liberty tremmac t-5 and has run a best of 10:62 1/4 with the t-5.

that trans cost me 700 dollars to have built. i since have put in a turbo 350 and it has proven very low 10sec 1/4 times. im glad i swapped and ill never look back