Zed'er

I just purchased a set of Comp Cams roller rockers 1412-16, and was wondering if I need to use guide plates with them? I have to get my block line honed and would take the heads in at the same time, if need be. Building a budget 350, and trying to save as much as possible. If guide plates are needed, can that kind of machine work be done at "home"?

Sonix

iTrader: (1)

what heads are you using?
roller cam or flat tappet?

i'm not familiar with those rockers (via the p/n), if you could save me the time, do you know if they're self aligning or not? (I guess that's the gist of your question, but...)

do at home: do you have a mill at home? drill press? if not, doubt it.

Zed'er

They are non-self aligning. They are for a standard hydraulic flat tappet cam. I do have a large drill press, and access to an even larger automated one. The heads, I'm not too sure of. I will be moving all my stuff across town to my garage later this evening. I believe I have some 441's, 462's and some other set of smoggers. I have a set of 327 heads that already have 2.02's in, but I'll have to check the numbers on those too (I know they are not camel hump).

Apeiron

If they're non-self-aligning, you need guideplates or you need slotted heads.

Zed'er

Do you mean elongating the actual holes where the pushrod goes throught the head? Is it usually expensive to get the bosses milled down for guide plates?

iceman02

iTrader: (1)

No, some heads have a slotted hole for the pushrods. The slots are wide enough for the pushrods, but not wide enough to allow the pushrod to move side to side, thus acting like a guideplate. Other heads have big pushrod holes that, without guideplates or self-aligning rockers, would allow the pushrod to move side to side. These type heads will require guideplates or self-aligning rockers.

Zed'er

So what actually makes a rocker self-aligning? I thought roller cams required self-aligning rockers.

Apeiron

A self-aligning rocker has flanges at the tip on either side of the valve stem to keep the rocker and pushrod from twisting out of position. Non-self-aligning rockers don't have these flanges, so guide plates or the slots on the head limit to the motion of the pushrods to keep things from twisting. Because the pushrods are rubbing against the sides of the slots, hardened pushrods are needed as well.

The cam doesn't have anything to do with whether the rockers are self-aligning or not.

tommy z-28

iTrader: (1)

Can self aligning rockers (from a 92 roller block) be used with 416 heads with slots, and stock gm pushrods from an engine with the slotted heads (non-self aligning rockers)?

Sonix

iTrader: (1)

if you have a drill press, you should be able to use an endmill and take down .4" or so from the rocker studs. (then be using collared threaded rocker studs as well).
the guideplates are dirt cheap, hardened pushrods are fairly cheap too.

ape - I guess my stock 416's use pushrod slots in the heads, therefore have stock hardened pushrods? I thought you only needed to buy hardened pushrods (among other reasons) if it were rubbing against the guideplates...


tommy : you usually want only 1 method of aligning the pushrods/rockers, pick one.

1) slots in heads
2) guide plates (cheap)
3) aligning rockers (very pricey)

tommy z-28

iTrader: (1)

Sonix:

Crap. I have a whole set of self aligning rockers with pushrods. Can I drill out the holes in the 416 heads to the same size as stock self aligning holes and use all the selfaligning hardware. Or is this a bad idea.

Zed'er

So, I would be able to use these rockers as is on one of my 305's without guides (they are all 416 heads) because the stock rockers on them now do not have any sort of flange on them, or push rod guides. But I would need guides to use them on a typical 350 head. I might have a set with screw-in studs already. I assume they would still need to be milled down by the thickness of the guide?

I'de use the 416's on the 350 if I were to put 1.94's (which would be cheap for me as I have a valve machine and seat grinder) in but I am using domed pistons, so there goes that idea.

Sonix

iTrader: (1)

tommy: I'm not an expert, so don't take my word as gospel here, but you should be able to enlarge the pushrod slots, and use the SA rockers, you *may* be able to use both, but like I say, i'm not an expert. Someone else here would know....

zed'er: you own your own valve machine and seat grinder, and you're asking questions about this? geez, how much was that machine???

Zed'er

Actually, it was free (inherited), but technically, it's my wife's, lol....