In the next couple weeks, we’re planning to swap the 700r4 for a TH350. I’ll provide as much info as possible about the current and future combo. This is strictly an 1/8 mile bracket car. It will never see the street. I don’t know what it weighs yet, but it’s completely stripped down to aluminum dash and single race seat. Electric water pump and alternator are the only accessories. Enough weight has been shed that the front end sits so high it almost looks like a gasser.

CURRENT- 350 flat top with Vortec heads. Springs to support .500 lift and 1.5 roller rockers. I don’t know what cam is in it other than the PO said “it’s an RV cam”. Whatever that means, aside from probably making low end torque. It is a flat tappet. Edelbrock rpm and Holley 750 DP. Stock rear end, not sure the gearing. Car originally is an 89 Firebird 305 Tbi.

FUTURE- we have a 383 eagle bottom end being installed at a machine shop now. The plan is to run nitrous as that is what we’ll have the gap set for the rings and then determine future roller cam selection.

Hoping to make 500+ and run 7.0 index. A 9” rear end is in the plans probably for the fall and before the 383 goes in.

But, we have someone offer to help us with the trans swap in a couple weeks and I’d like to order a converter. Any advice would be greatly appreciated.

 

I assume you want a converter just for the future 383 nitrous engine and whatever it ends up being, you’ll run with it in the current 350?

i liked Edge racing and PTC

 

Yes. I don’t know much about converters, I just don’t want to buy anything twice. That was sort of my thought process on the 750 carb. It’s probably more than I need now, but should be a good fit for the 383. Hoping to accomplish the same with the converter.

 

Spec out the motor, get an idea where you will make power, rpm range etc. plan the tire size you’re gonna run and gearing. Then call one of the converter companies you want, talk it over or fill out a spec sheet and have them put something together. Good news is, if heavier nitrous use, the converter will be fairly tight, and act abit tighter on the 350 probably since stall speed is based on torque output, so it may work ok for both for now. But a good 383 shouldnt have too much issue goin 7.0’s. Could get there on motor, def on a 100-150 shot. And a 150 wont change converter too much. You’ll probably want something that stalls closer to 4000 for race. Touch tighter if always spraying. On a weaker 350 it may stall 500 or more rpm less. Hard to say, a rv cammed 350 has a lot of off idle torque, but it will still be fun with too much converter. Its a sacrifice to buy once cry once…

or just get a cheap shelf unit 3000 stall for the 350 and get a good one later

 

I'd reach out to a reputable converter company and give them the details of your setup and see what they recommend.