AK71CutlassS

Looking to do a 350 to 455 swap this summer. I have 3.73 gears. The 455 will be around 500HP and 550-600 on the torque. I do have a TH400 that can be rebuilt. I will be 50/50 HWY AND STREET. what's my options? With the least amount of mods to car?

oldcutlass

The least amount of mods would be to get the T350 beefed up dramatically if that's whats currently in the car. The best option is to rebuild and beef up the T400. This will require the addition of a kickdown switch, modifying or replacing drive shaft, moving the trans xmember back and some ebrake cable changes.

Olds64

As long as the TH400 has a BOP bell pattern that would be an excellent choice. No need to hunt for a transmission when you already have one.

AK71CutlassS

Yeah i was thinking about overdrive but not sure yet. Yes the TH400 is BOP. I will get some quotes from local shops on rebuild prices.

AK71CutlassS

Should I get it built for later down the road adding the gear venders OD?

Olds64

A Gear Vendors unit is quite pricey. You would spend much more on the Gear Vendors unit than you would on a rebuild. That being said, I've only heard good things about Gear Vendors.