PonyKiller87

Im trying to pick out the new parts that I plan on getting for my engine but Im not sure about a couple of things. What I want to do is put a set of the Comp Cams Pro Magnum Roller Rockers on so I figured I should replace the springs, retainers, and all that stuff while Im at it to. I looked on the comp cams web site and picked out the valve springs they recomend for my cam.
My first question has to do with some advice Vader gave me a while ago. He said I should remove the Spring Rotators(I think thats what he called them, I put a picture in the yellow arrow is pointing at them). Anyways I looked at the comp cams retainers and they look nothing like the stock ones(red arrow) they are flat and not cup shaped like whats there now. So do I reuse the cup shaped part or is that not needed with the new retainers? Along with this, Do have to put shims in to make up for not having the rotater things??? If so how do I know how much to shim them?
Ok next question, With the Roller rockers they come in 1.52 ratio and 1.6 ratio. If I got with the 1.6 will that mess up the valve geometery that Ive heard people mentioning on here. Will this affect the length of push rods that I need?
Any help with this would be great. Thanks and sorry about the long post.

RB83L69

The thing you have the yellow area on is a rotator. It exists only on the exhaust Throw it in the garbage.

The thing with the red arrow is an oil splash shield. It's equally ineffective and worthless dead weight. Throw them in the trash and use PC type seals, I prefer the Teflon ones from Crane or Comp.

What I usually have done, is to get the machine shop to cut the spring pockets all the same; I have them use a .030" shim for 1.25" springs, and cut the larger pocket only to that depth, to avoid hitting water; that way they're alot easier to shim for correct installed height.

The very top piece is the retainer. Get those with your springs, to match whatever springs you use.

Rocker ratio does not mess up valve train geometry, if it's set up correctly in the first place. Different ratio rocker arms look the same to the cam, lifters & push rods, except that the push rods are slightly closer to or farther from the rocker studs. For optimum geometry, you choose push rod length so that the tip of the rocker travels (slides or rolls) the shortest distance across the tip of the valve as it moves through its operating cycle.

PonyKiller87

Ok

Rotators and Splash Shields - Garbage

By PC type seals do you mean the ones that look like a little cap as opposed to the o-ring kind? If so I already have those, not sure if they are teflon though.

The heads are on and it all back in the car so I dont think I will beable to get any machine work done. ( I had them in to get threaded studs during the summer)

I picked the steel reatainers that are recommended for the springs, the titanium ones were just way to much money. (everything will be comp cams)

I did some more reading about the geometery on comp cams web site and its pretty much what you say, doesnt seem to tough. I think Im going to wait on the pushrods and see how the stockers fit then go from there. Ill probably go with the 1.6 rockers.

Now heres the new question. There are 2 different springs recommended for the cam that I have, how do I determine which to use? Ill attach the spring table from comp cams, the springs are the 981 and the 983. They look like they are almost the same?

RB83L69

The 983 doesn't have a damper, the 981 does. The 981 would be the preferred one.

The Perfect Circle seals are the ones that have a metal band around them, that clamps them to the valve guide. They're Neoprene or Viton or something like that. The Teflon ones are just like them, except for the material. They're in the Comp catalog so you can look at a pic there. There's another type, commonly referred to as "umbrella" seals, that look like little umbrellas; those are slightly larger than the guides, and stick to the valve stems, and ride up and down with the valve, and are merely a splash shield over the guide. No metal band. If that's what you've got, I'd recommend replacing them while you are doing the springs, with the PC type. You can get those from Fel-Pro also, I don't recall the part # though.

PonyKiller87

ok cool, I have the kind with the little clamps on them.

Well I guess that about does it then until I get the parts and I can see how the push rods look.

Thanks for all the help.

PonyKiller87

RB,

I have another question related to all this stuff that you may beable to help with. Like I said at the begining I am getting the Comp Cams Pro Magnum rockers. My question is they dont list them as Self alinging or non SA, so A how do I know what they are, B how can I tell if my stockers are SA, and C will I need guide plates if they arent SA ? The rockers and everything on there now are the stock stuff for a 87 L98.

RB83L69

A & B. Look at the tip of the ones you have now. If there's a little ridge on either side of the tip, spaced apart such that the valve stem wuold just fit in between them, they're SA. Since your motor is 87, it should have that kind. They list them as 86-back and 87-up, you have the 87-up variety.

C. There are 3 alternatives for locating the rocker on the valve stem tip. They are: slots in the heads that fit tight to the push rods where they pass through; large holes in the heads where they pass through, and guide plates; or large holes in the heads, and SA rockers. One and only one of these must be installed: no more and no less!!!! If your heads are stock 87 pieces, they will have the large holes, so they need either guide plates or SA rockers, but not both.

Slade1

The picture he has of his heads look like they're the self aligning type rockers.