Putting 455 in son's 72 Skylark and we have 2 th350s that were behind buick 350's. Will one of them work for a while. Do we need different torque converter on a big block? Or is it a waste of time sell em both and buy a 400 and get stall converter. Just trying to save money right now and with 2 we could blow one up and still have a spare. Maybe buy a good converter and use one of the th350s. They both have stock converters right now and stock internals.
It will work unless you monstered the engine and are gonna beat it like Michael Jackson. (no neutral drops, no reverse to low "J-hooks", no sprag rolling burnouts) Unless you know the condition of the trannys, you might get real good and playing the tranny hokey pokey. You will need to move the crossmember, different yoke and new driveshaft. If you are in a location that you can sell them and get a TH400, that would be my preference. (and I would do a rebuild) Converter is 12 inch in the TH350 and 13 in the TH400. You will get a bit more performance from the smaller converter due to less mass, and bit more stall behind the BBB and about 10% less parasitic loss. But he's young, and a lot of the fun is smiling and doing this stuff over and over, until you get older and then you just sigh and do it over and over.
I have a TH350 behind my 455. Ran a 13.03 @ 101 at the Nats this year with Drag radials. The converter you use will depend on matching it to cam you are using.
Sure it will work. Torque converters are interchangeable between 350 and 400, but the torque of the 455 will stall the 350 converter higher. If you aren't hooking it up with sticky tires at the track, it should be fine for awhile.
Ya just around town cruiser stop light racer for now don't mind changing trans out few times if needed So probably just run them for now with or without a stall depends on cash when it goes in I guess if they break I guess they are free.
I have a TH350 in my Camaro behind a 500hp 454, no slicks or traction devices but it does foot brake launches on the street with a 275 drag radial or with a 235 street tire for 50' burnouts.
I have gone thru a few TH350s with small block engines, once changed over to TH4oo my problems became much decreased. Switch Pitch only comes in a 400. Bruce Roe
Properly built, a 350 will handle a very stout 455. Properly built means more than a cheap shift kit abs a stock rebuild kit. Machine the direct drum to fit a 5th friction, use premium friction material. Replace all the bushings. Leave the 1-2 accumulator functional. You could delete the 2-3 accumulator with no trade off. The later cores usually have bearings instead of thrust washers. A aftermarket pressure regulator spring would be a worthwhile upgrade. Replace any plastic accumulator pistons. Unless your making 650 plus hp, a 350 will live. If your making less than that and tearing up transmissions, it’s time to find a different builder.
I’m curious, what does your car run/weigh? Since this is a Buick forum, I’m guessing it’s safe to say the sprag didn’t break due to excessive RPM! Did the trans hit 2nd gear hard enough to knock the dash out of the car? I have built many 350s for 3700-3800 pound cars that run low 11s with nothing more than a 5th clutch in the direct and some simple cheap valve body upgrades. I haven’t luck with the EBay intermediate sprag races. I think it’s better to either use the factory sprag, or make sure you buy a race from a reputable company.
I was running 2.56 gears and doing burnout 1-2. Trans guy said hard on it better to do burnout in 1st or go 1-2-3. I put the drum in anyway to be sure.....
