304 harmonic balancer on a 360

[bjf498]

Hey guys newbie need a little info here.

Ok I have an 83 cj7 that had a amc 304 in it when I got it the 304 had some wild cam in it but other than that it was stock. Well I rebuilt the 304, and after I put around 15,000 miles on it the cam gear that drives the distributer failed thanks to a new hei I got from 4wd. I didn't know the gears would not work together.

I tore the motor down to inspect the damage it wasn't too bad but I wanted more power anyway. So I got a rebuilt 360 from s and s engines, and put all my 304 stuff on the 360 the guy at s&s said it would work fine. So far it has i don't have any bad vibrations or anything. What I want to know is can you really use a 304 flywheel and balancer? Or is it killing my internals?

And also do you think the hei killed the old cam gear because it wasn't matched? I have a set of factory matched gears i'm going to use on the 360 with that hei?

[tufcj]

Welcome to Bulltear.

AMC V-8s are externally balanced. Although the stroke is the same on the 304 and 360, the 360 has bigger (thus heavier) pistons, so the balance is different. Part of the balancing is the harmonic balancer AND the flywheel/flexplate.

You should have the 360 balancer AND flywheel/flexplate. The balancers are very different if you hold them side by side. I've seen a 304 flywheel used on a 360, it's about a 50/50 shot if it will vibrate or not. It's a lot of work to change if it does, so I'd just make sure it was right the first time.

Bob
tufcj

[bjf498]

Thats kinda what I had figured, but just because I cant feel any viberation doesn't mean its not there right?

[tufcj]

As far as the cam/dist gears, there are at least 3 "flavors" out there that have different pitches (maybe more). They are not compatible when mixed, so it's always advisable to replace them a known matched set.

Bob
tufcj