87 L98 TPI "pee pee pee pee" noise coming from the valves

The stamped rockers used on 87+ L98's are self aligining. As you stated above, you only need one of the 3 ways to align the pushrods. Either slots in the heads, self-aligining rockers, or guide plates. GM put plates on the heads and installed self-aligining rockers. FWIU the plates are not functional as guide plates. So, if he put non-self-aligning rockers on he's got a push rod thats wobbling back and forth, probably against the plate creating the vibration and squeak.


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thanks so much cobalt !!!

I googled the casting number on those heads and plates and came up with this: L98 Retainer Squeak . I think this guy has the same problem you have.

wow this is getting more and more confusing ....

I'm following you.

What's the great unknown here is what type of rocker is being used...

The link above doesn't want to work for me, can you post the url?
Edit- Nevermind. I think the prob's on my end.

If GM put SA rockers on the 128 heads
anything bad could happen if i switch to NSA + GUIDEPLATES ?

Whats the visual difference with a Stamped SA an NSA ?
Thanks

remember i have the zz4 cam...should i replace the studs ?

http://www.thirdgen.org/techboard/t...r-pushrods.html

Yes i saw that link..so i think i will be fine with NSA + guideplates.-
Now about the pushrod...which lenght is recommended ????
thanks

The rocker arm tips have a notch which the valve stem tip sits in to keep it centered.

Got it !
SA on the left ...NSA on the right !
i think i will use NSA because my valves IIRC doesnt have that little head
for the SA to align

Except yours are stamped if they're stock. No roller, but yes. If you do use the NSA rockers put in real guide plates and hardened pushrods.

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You might have less of the valve tip showing if the valves were cut during a rebuild. But it's there.

And if the tip was cut, this could allow a SA rocker to contact to top of the retainer. That could cause the squeak, as mentioned.

Non SA rockers and hardened p-rods w/proper g-plates it is, then!

BTW, I wonder how well the nylon-like guideplates work. Supposedly, you can use non-hardened pushrods w/them.

AFA p-rod length goes, there are length checkers that are inexpensive that'll let you measure for the correct length. Comp has them, IIRC. Others as well, I'm sure.

You want the swept area of the valve/rocker tip to be centered on the valve tip.