When one is using roller tip rockers are guide plates needed
 

I'm just curoius because when I had my heads build I had guide plates installed but when looking at another set of heads im thinking guide plates arent nessasary. I cant see how the push rods could fall out. The comp package said, 55-70 something have self alligning rockers and guide plates arent nessasary but these 83 heads look like they could hold the push rods inplace without guide plates. Am I on crack? Whats the deal.:confused:
Thanks.
SSC:)

I wouldn't think twice about adding guideplates when unneccessary. It's insurance. I think it really depends on the type of rocker arms and/or style of head. i.e. non self aligning need guideplates and self alligning could depending on the head. Im probably wrong. You're using hardened pushrods, right?

Yea im using hardened push rods, the ones that came with my crane solid cam kit. I'm just thinking guide plates are not nessasary for most applications. I would like to put some roller tip rockers on the Firebird but I dont want to pull the heads and as far as I can tell the heads are identical uptop. So I dunno.
SSC:)

There are 3 possible systems for locating the rocker on the valve stem tip: the push rod slots in the heads, guide plates, or self-aligning rockers. One and only one of these should be in effect.

If your heads have slots for the push rods that are no more than .015" larger than the push rods, then you don't need guide plates or SA rockers. If the heads have large holes, then you need either plates or SA rockers. If your rockers are SA, then you need to have the large holes without plates.

The overall best system is guide plates and screw-in studs. You should use that system if possible.

i wonder how many time RB has had to type this response? saved me from doing it, and he's better at getting it said than i am.