T5 behind a big block?

How well will a T5 hold up behind a 396? I don't race, but sometimes burn a little rubber......searched for awhile but nothing on a big block. Thanks

 

It all depends on how you drive it, what the vehicle weighs, and the gear ratio in your rear end. If you don't try to hard launch and power shift with it, it should be fine. I've got a t-5 behind a 300+ horse SBC in a 1900 pound Roadster Pickup, and I'm not having any issues at all. Then again, I'm not going crazy behind the wheel either! Good Luck.

 

I had a NWC T5 behind a 402 in my 66 C10 longbed fleetside and it lasted through quite a few John Force style burnouts, greatly impressing all my friends... until I twisted all, and I do mean ALL the teeth off the input shaft. In hind sight, I wish I would've been a bit more reserved with the weight of my right foot.

 

The highest torque rating available in a T5 is the aftermarket T5z at 330 lb/ft. A decent 396 will make 400 lb/ft. If you put your foot down, it's over. Do you really want that handicap always with you?

 

To my knowledge, GM never put a T5 behind anything bigger than a 305. If they won't put it behind a 350, what do you think your BB will do?

Devin

 

The torque ratings on T5s are misleading. That said, I wouldn't run a T5 behind a big block...will it last? You could baby it along and it would last forever, but where's the fun in that?? One hard 2-3 shift and it's probably over with a big block...

 

As long as you don't run slicks, drag radial etc. you should be ok. I made 200+ passes with wc t5 in my 2,700lb car and slicks pulling the front wheels on launch. All went ok till I swapped in a kevlar clutch i'm trying a Tremick t5 with some G-Force upgrades at the track this weak.

 

You want my opinion? A stock 396/350 would be taxing on even a world class T5 with how much power it makes. It's been said, one hard 2-3 shift and it's ka-blammo.

I'd be keen to just sell the T5 to someone with a small block and toss a T56 behind it. It's apt to take a WHOLE lot more abuse.

 

Agreed, those transmissions can't handle that kind of torque. Burnouts are one thing, there's less load because the tires aren't hooking. But one real good 1-2 or 2-3 shift where all that power connects, especially in a heavy car... forget it. You'll blow that trans all over the pavement.

 

I wouldn't run one any longer than I had to on a decent small block, much less a big block, unless it was in a very light car. I ran a WC Ford in a supercharged (517rwhp) 5.0 Mustang coupe once, and it didn't break in the short time it was in there, but I had a Tremec TKO ready just in case it did. Small motor, but the Vortech was pullied for about 15lbs boost so it had plenty of torque, even down low.

If you NEVER powershift it, and don't do any racing with sticky tires, it might last for a while. I'd pick up an LT1-style T56 ('93-97 F-body), though, and sell the T5 if it were me.

 

Its great for cruisng down the highway but its the weakest link in the drivetrain. I always have that doubt when I punch it.

 

I'd tend to agree with Ernie on this one. He seems to really know his stuff about T5s.