I bought a set of Comp Cams stamped steel roller tip rockers for my SBC and the info sheet that came with them says you must use guide plates with these to maintain proper rocker alignment. I really don't want to have the heads machined for guide plates. Anyone have any experience running without them? 350 horse cam, .030 over, maybe make 300-325 horse out of it with the flat top pistons. Thanks, Dennis
I've done it many times without the guide plates and hardened push rods. Not saying it's right, just saying I didn't have any problems. If I'm after any serious power I have the guide plates in anyways. The 327/350 horse cam, which is what I assume your'e using isn't that radical but the concern is probably with misalignment.
You could also try rebuilding your engine next to a guy sandblasting too. The bottom line is, it might work but your guaranteed to have problems.
You didn't mention the type of casting your sbc heads are. Early pre 86 heads have pushrod guides cast/machined into head. Later heads and Vortec heads require a "Guided" or rail type rocker..
IMHO, guide plates are cheap insurance for your cam choice. Are the heads off the engine? This is not a real big expense and any decent shop should be able to turn it around quickly. Bob
You have a basic stock Chevrolet setup, less rockers, that has worked reliably on millions of cars since 1955. My left turn customers, in entry level classes, use much wilder cams and rockers with the same stock pushrod guides. Guide plates in your situation are an expensive waste.
Sorry, hit the send button by mistake. Just send those back to Comp and buy self aligning roller rockers. Several companies manufacture them Comp, GM Perf Parts, Crane etc. That way you don't need guide plates.
Those heads you have, have small enough push-rod holes to keep the rockers aligned. to put guide plates on,the heads would have to come off and the rocker arm bosses machined down and treaded.
As well as the pushrod holes opened up. My experience is thet the roller tip rockers are basically a gimic and net so little in performance that you can only tell it on an engine dyno.
Thanks for all the responses. Just thought the improvement on the valve train geometry would be better, not looking for any horsepower gain. I'm not going to pull the head to do that. Probably go back with the original slots. Don't think GM has the old style anymore though. Need something to clear the stock valve covers that are made in the US. Dennis D
Dennis, They are just a stamped rocker with a roller tip correct? On old heads with small pushrod holes they should work just fine.
Correct, old heads, stamped rockers with roller tip. I thought I've seen motors set up like that, but the old memory ain't what it used to be, among other things Dennis D
I think the info that comp cams gives out is considering that they may be put on late heads. I have seen a lot of fellas run roller tip rockers on older engines with no guide plates. If you get to the point that you are going to wing it past the 6,200 float on that cam you may have to consider something different.
Them high revvin' days are in the past, LOL. Looking for more reliable. If I ever get the rod done I want to drive it out to Cal. to see my daughter. If it sees 6,200 someone wake me up, I've fallen asleep with my foot on the pedal! Thanks again for the help. Dennis D
Don't tell Gene Schwartz that. I think he's still shifting a small block at around 12,000 rpm. And he's winning!
Under some conditions roller tip rockers reduce side loading on the valve stem and reduce friction. But, the benefits are small. Most people don't realize that at high RPMs(varies with cam profile & spring pressure) inertia renders the rollers unable to reverse direction fast enough, at which point they just skid on the valve tip like "regular" rockers. Roller cam followers eliminate a LOT more friction than roller tip rockers. Rockers that have bearings instead of metal to metal or balls or pivots eliminate some friction.
I try to stay away from Comp Cam parts. I installed what I thought was hardened push rods along with guide plates. Made a 600 mile trip and broke 2 push rods, they wore through on the guide plates and snapped! I called Comp Cams and told them the situation and they insisted they were hardened! I have a machinist buddy who had a rockwell hardness tester and we tested them and they were not hardened! Comp Cams would not stand behind them and I was out the pushrods, guide plates and my time & labor to repair it! I removed the guide plates and went with "Sig Erson" hardened one piece push rods to replace the Comp Cam ones. You really don't need guide plates unless you plain on running some higher RPM's. I have a buddy who's been building high performance motors for almost 40 years and he keeps telling me stay away from anything Comp Cams, he's had terrible luck with them!
I'm going to use a set of camel hump heads, they have guide plates. I thought they were factory...no?
Huh? I'm missing something...again. If my camel hump heads have guide plates, is it safe to say they were added at a later time?
I have had some of those roller tipped rocker arms running on my 72 Vette with no guide plates since the early 90s and no problems at all. And I used to get on it pretty good before I got old.
I think what is being said is that the early (pre 86) stock chevy heads have small enough pushrod holes in the head, that the hole can serve as the pushrod guide, and there's no need to also use the guide plates that are bolted down by the rocker studs. Later heads have bigger holes, and need to use the guides so that the pushrods don't move enough that the rocker tip falls off the end of the valve stem.
Easy,reliable way to check for hardened pushrods is to scrape the pushrods in question with a good pocket/buck knife. You will NOT get any shavings if the pushrods are hardened.
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