Hey 'sup guys.

I've bought a ZZ4 camshaft to put in my new 350. My previous engine was an all mighty 305 TBI from a 89 Camaro.

The 305 was using a HEI 2 connectors type distributor. I red somewhere that if I wanted to use that distributor with my new ZZ4 camshaft, I'd have to change the gear on the distributor. So that's what I did, and bought a 10456413 melonized gear... and it's loose on my distributor shaft. There's a lash of about 1/16...

How come? So I need to change my distributor? What if I run the engine with my old gear?? What's the difference between 'em (exept what they are made from).

Any help would be GREATLY appreciated.

Thanks a lot.

 

Sounds like you got the wrong gear, there are 2 different shaft sizes GM used. The factory gear is supposed to be melonized anyway, just use it.

 

You know I've got a ton on the shelf, but never looked at 'em side by side. I'm told they are different, and it will chew up the cam..

 

One is Bronze alloy (for roller cams) the other is steel (for flat tappet cams)


~M~

 

If you are re-using the distributor from the '89 LO3 TBI, you do not need a different gear for the ZZ4 cam. Both are factory roller types, and like madmax said, they use melonized gears on factory roller engines.

You don't want to use a bronze gear on a factory roller cam.

 

Thanks a lot guys... I will follow your recommandations!!

 

I wanna jump in on this. I know that you need a special gear to run roller cams, but what if you going the other way putting a ZZ4 dist. onto a flat tappet cam?

 

No problem. The melonized gear will work on either type.

 

Thanks.

 

GM factory roller cams don't require a bronze gear like most aftermarket roller cams do. They somehow integrate a hardened gear onto their roller cams that is basically the same as on their flat tappet cams.