91greenbird

iTrader: (4)

what kind of rocker arms does it take self aligning or not does it use guide plates? How much lift can it handle without being machnined. What kind of locks and retainers does it use? What lenght pushrods. What can i expect a shop to charge me for installing 1.94 int valves and 1.5 exhaust valves new seals (basically rebuild the head)?

Air_Adam

416-equipped engines did not use self-aligning rockers in stock form. That only started in the mid 90's if I remember right. The 416 heads had very narrow pushrod holes drilled in the heads to keep them aligned.

Sonix

iTrader: (1)

That's right. Pushrods are sized based on the cam. Flat tappet length for flat tappet cam, roller length for roller cam. It takes normal retainers and locks. If you want to upgrade to 10° you upgrade both retainers and locks.
Cut for larger valves cost me $80.
You have to measure to find out how much lift it'll take. You can use offset locks to increase that.

91greenbird

iTrader: (4)

so its not self aligning and it doesnt use guideplates? Its a flat tappet cam summit only list length and i have no idea

Sonix

iTrader: (1)

There's three ways to align your rockers:

Most factory heads (pre 1987) simple used a slot for the pushrod. You then did NOT use guideplates, and you used NON-self-aligning rockers. Common, works great.

Method two and three is to drill out the slot so it's just a hole. Some aftermarket heads come this way. You can then use self aligning rockers, OR guideplates.

Use one method only. There is no "good" or "bad" way.

If your pushrods aren't bent, just reuse them.
Otherwise;
Pro-form, "stock length".
http://store.summitracing.com/partde...w=1&N=700+150+

Looks like thats 7.794". To be honest I never remember numbers like that. I just use "stock length". Depending on the cam and heads, you may want to just buy a length checker, mock it up, and buy the length you need. They are sold in .050" increments.

chesterfield

From what I've read, Chevy switched to self aligning rockers across the board in 1987. from what I've seen in person, 1987 up heads have narrow slots. Here's a pic of a 14102187 head showing this. that is a 5/16" pushrod. I don't see how the slot could be any tighter than it is.

Sonix

iTrader: (1)

Yea, Chevy went to SA rockers in 1987, so they shouldn't have been using both. But I can't argue seeing the slot, and SA rockers on the same head .
My 1982 416 castings had the slot. *Most* post 1987 heads had the hole rather than the slot (from what i've read). The punchline is that you really only NEED one way to guide your rocker, pick your favorite one. Generally if you have more than one, it can cause bind.

chesterfield

I don't know why you would say that chevy shouldn't have been using SA rockers on a head with a slot. Where did that rule come from? I can't recall ever seeing a 1987-up head with a hole and not a slot. But I can recall seeing alot of them with a slot like the one in the picture.

Sonix

iTrader: (1)

Well you don't need more than one method of aligning the rocker/pushrod. If you have more than one you can induce bind, that's why I say they "shouldn't" be using more than one. This is more referring to guys who use SA rockers and guideplates (no-no).

Aftermarket heads usually have just a hole, and you can use either guideplates or SA rockers.

The factory heads i've seen have the slot, but they also had non-SA rockers. I'm trying to remember what the Vortec heads had that I was looking at before....?