Switching from 258 to 304. Need help!

[Hacksaw]

Hi, I just bought a nice running AMC 304 v8 with the CJ engine towers to bolt this thing in. My question is, my factory trans is the TF999. Will the flexplate from the 258 bolt on the 304, and is it the same balance as the 258? I know everything elese will work, just didnt know if I needed a different flexplate? Also, will my factory ignition box work with the v8? Thanks guys.

Shawn

 

[John N]

The factory ignition box will work, there's no difference. You do need to get a 304 flexplate. They aren't too expensive, I got one for my 360 from 4 Wheel Drive Hardware. AMC V-8s are externally balanced, the flexplate is unique to each displacement engine.

 

[Hacksaw]

I asume that the torque converter will still work. If so, will this produce a higher stall speed with the v8 rather than the v6? Most of the apps. I have delt with like, cheep hot roders using a vega torque converter which is arround 8 inches will give you a much higher stall speed than a stock torque converter behind a small block chevy engine. Will this be the same with the AMC apps?

 

[John N]

Smaller torque converter equals higher stall speed. I run a stock converter, the same one I used with a 258. You don't want a higher stall speed for offroad, it would keep you from being able to crawl or go as slowly offroad.

 

[RobertFoster1977]

Hacksaw, you're going to need to change the frame mounts ?

 

[Ron84cj]

Hopefully he finished his swap by now. This thread is from 14 years ago. Lol

 

[Oakley]

Well sometimes it takes awhile