[leejoy]

Hi

Ok, I finished the motor, got the subframe connectors on and have a 3.08 gear posi rear end with stock suspension. It's a 72 Nova with a 550 HP BB Chevy. The trans is a stock Turbo 350 with a new shift kit. I need to start planning now for this next fall's work on the car. Should I keep the Turbo 350 and rebuild it - stronger, or put in a Turbo 400................I"ve never rebuilt a automatic trans..........

Before you say "trade it in for a Turbo 400" remember the turbo 400 is heavier, longer (have to shorten drive shaft) and the crossmember has to be relocated and possibly replaced with a different one. that's a lot of extra work and more money that I don't want to spend and do if it's not necessary. Right now the Turbo 350 is holding up but perhaps not for long. After this recent engine rebuild (and the upcoming larger carb) I won't be surprised if it destroys itself under a load taking off from the line. I've seen performance professionally rebuilt Turbo 350's advertised for up to 500+ HP. I know very little about this and need several opinions. By the way I have standard street tires in the back, little wider than stock but not your "hook up" racing slicks. So if your thinking this car is going to pull the front end off, it won't because it smoke the tires instead. that works in my favor as far as not destroying the trans right?

thanks for your reply.

Lee

[Centerline]

Although the TH-350 can be built to handle that amount of horsepower it will in the long run cost less to go to the TH-400 and that trans will last longer. Relocating the crossmember is not that much work and shortening the driveshaft will cost about a hundred bucks. There's a reason GM put the TH-400 behind their high performance big blocks you know.

[Chazmac]

The short T350 and short T400 are the same length overall.
Getting a T350 to live in your car is not difficult, but there are some things to consider.
I sent you a PM with some advice

[leejoy]

Originally Posted by Centerline

Although the TH-350 can be built to handle that amount of horsepower it will in the long run cost less to go to the TH-400 and that trans will last longer. Relocating the crossmember is not that much work and shortening the driveshaft will cost about a hundred bucks. There's a reason GM put the TH-400 behind their high performance big blocks you know.

thanks buddy. I am considering your comments.

[icemangearhead]

I have been running a TH350 behind a 650 HP 427 for 10 years and it has yet to fail me..I am running TCI internals but it was home built. I am running a 3000 stall and a 950cfm carb.
Stick with what you have till it blows. It will be a while. If this is your dailey driver go to a 400.
I have lots of friends that run BBC with TH350 and it will let you know before it completely goes out. If driving daily the performance will gradualy fall off for a couple of weeks. The first gear to go will be Reverse. once this happens it is time to start thinking about your other options.