ztrips

OK, my stock LT1 heads have guide plates, but I'm reading that the LT4 hotcam kit uses self-aligning rockers. Does that mean the guide plates must be removed? If I'm only buying rockers, should I get non-aligning rockers?

Confused....

mothersworry

I run the 1.6 non self aligning Crane cams gold series. Seems to be successful for eveyone that has used them. You may want to go with 7/16 studs and guide plates. Just a thought.

FD2BLK

For almost the exact amount you can get 7/16 studs, guideplates and harden pushrods with non-self alinging rockers. I went this way because if I ever need to replace the rockers I have a lot more choices and they will be cheaper.

ztrips

Are there any clearance issues with the crane gold vs comp pro magnums? I'm running the '92 mag valve covers... I've removed the drip tabs already.

FD2BLK

I don't know about all valve covers but there is a diference. The Pro-Mags use larger trunions and the problem is not with hitting the top but rather they hit the baffles. The cranes fit better and require no mods other then the drip tabs you already removed. The Pro-Mags are not that big a deal to get in there and here is a link to better explain.
http://www.hotss.com/Members/scott_vaca/pro-mag.htm

Corvette Kid

What LT1 ever had guide plates stock?

ztrips

Mine I guess... 1992. It had them on there when I took the heads off. No indication that the previous owned put them in. Factory cam, lifters, pushrods, why add guide plates... I've heard that GM used guide plates with self-aligning rockers to make assembly easier. Not sure if there is any truth to that...

Corvette Kid

It's quite possible. Many L98s did, I just never heard of it on an LT1. But there are quite a few differences in early and later ones , different head castings, etc.

fixit

The link mentioned for modifying valve covers deals with the older metal covers, what the h-ll do you have to do with the plastic covers????

VenkmanP

They are just for assembly. They are not guide plates.

ztrips

OK, so I guess the gaps on the guide plates are .374" and I need .324" gaps to run non-aligning rocker arms. Any thoughts??

Tom Piper

The early LT1 engines had guide plates from the factory -- they also have self-aligning rocker arms.
The purpose of the guide-plates was to hold the push rods in position until the rockers were put on.

The later LT1 engines had heads with smaller holes in them that supported the push rods until the rockers were assembled.
So, the early LT1 heads are different than the later LT1 heads.

My '92 LT1 came from the factory with guide plates and self-aligning rocker arms.

Tom Piper

mothersworry

Everything he said. My 92 had guide plates as well stock.

FD2BLK

I posted the link for an example, I have not done the corvette covers but they may be similar to the billit ones I did. I had to remove part of the supports for the bolt guides, it would be a simple job on cpomposit covers if it needed to be done

Here are some pics of what I had to remove, notice i only had to mod one side (The side the R/R trunions sat on.

ztrips

OK, so I think the plan will be non-aligning rockers with new CC guide plates and hardened push rods. I can just unscrew the studs and replace the guide plates and re-install the studs, right?

Hotred94

The LT1s that came with guide plates are not really guide plates. Like Tom Piper said, they are factory guides to hold the push rods in place during assembly, but they are not real guide plates in that they are loose fitting and they are not hardened. It makes no sense to put real guide plates on heads with self-aligning rockers because they will conflict with each other and cause premature wear. One will be forcing the push rod into the other. That is why the ones you have (if they are true factory pieces) will be loose fitting, because they are meant to hold things in place for assembly and not to actually align and hold the rods. I suggest you stick with the self-aligning rockers and don't worry about the assembly plates. Hope this helps.

ztrips

I've heard that if you're looking at running higher RPM's (I've actually heard over 5500.. and I will be..) then guide plates are much more effective than self-aligning rockers. I figure I'm replacing the rockers either way with rollers, guide plates are not a lot of money and all good pushrods seem to be heat treated anyway why not go to true guide plates and non-aligning rockers? Am I missing something?

Redeasysport

Your options are cut the drip tabs, buy a set of LT4 covers,or try to find an aftermarket cover that will probably need rework around the altenator are.