Why do advertisements say "Not for factory hydraulic rollers" and some say "for hydraulic roller cams", and some don't mention it either way?
All I want to do is buy a kit thats not ungodly expensive without any hassle. Cloyes makes a heavy duty true roller kit for about $30 but it doesn't specify if its for roller cams or not.

doesnt the roller timing chains have the thrust plate to keep the cam from walking? and I think the $30 cloyes timing chain is a roller but not the TRUE roller...the true roller is up around 60 bucks.(assuming its a double roller)

Ryan

All roller cams have to be constrained in some way because there isn't the bevel built into the cam to hold it the way "flat" tappets do (they are not flat but concave, that is why you can not mix them up on a cam swap).

The "factory" roller has a special step ground into the cam and uses a plate to hold the cam in place. After market vendors like Crane and Comp, and Crower, et. al. use a combination of roller cam buttons and thrust plates (shims) to hold the cam in place; and they require a specially reinforced timing chain cover to compensate for the trust of the distributor gear (driving the oil pump).

http://photobucket.com/albums/f63/3454545/?action=view&current=DSC02849.jpg

If it doesn't say it is for a roller it is for a flat tappet cam. Which are held in place by the valve springs holding the cupped bottoms of the "flat" tappets against the rounded cam lobes.


Larger Dave

Thanks... I think Im just gonna play it safe and get a new ZZ4 gear and chain. Thats the engine I have afterall, so I know it'll work. Too bad I can't have a dual chain/gear . It rubs on the block... :(