Going to get these.

They have some by Summit, Comp Cams, and Crane I believe.

What size are the stock pushrods, 5/16" or 3/8" ? Going with new hardened pushrods, is one better than the other sizewise? Do the both fit the head OK? Also, there is flat and raised....difference?

Guideplates:
Crane: Small Chevy 5/16" $24
Comp: Raised 3/8" & 5/16" $27
Comp: Flat 3/8" & 5/16" $24
Summit: 5/16" Flat $16
Summit: 3/8" & 5/16" Raised $17

There are no "LT1 specific" guide plates are there?

Thank you!

 

Guideplates: About any will do. I used Comp Cams.
Pushrods: 5/16 is stock diameter, 7.200 is stock LT1 length.

Get one-piece hardened pushrods.

 

As stated, the SBC uses 5/16" OD pushrods. Raised vs. flat guideplates is a pretty fine distinction. I prefer the raised, as they control the PR closer to the valve, but both work fine.

All pushrods are not created equal. Even if the O.D. is the same, the wall thickness is important along with the obvious differences like materials and method of construction. You want a PR that is strong enough not to flex, but no heavier than it needs to be. Stock or mildly modded cars can get along with a stock or stock replacement PR. Cars running bigger cams with higher spring pressures, especially if run at high rpm need a better PR.

I like the Comp Cams Magnum PR or equivalent. They use 0.080" CM (I think it's 4130) tubing. Stockers are a less expensive 1010 alloy and have 0.065" wall thickness if I remember correctly.

And getting the correct length is also important. Using a bigger cam and/or high ratio rockers requires a shorter pushrod. And you need a "case hardened" PR for use with guideplates, as also mentioned by "nateh".

Rich Krause