So, you have to weld up the Isky adjustable guideplates? I am thinking about going with these also but didn't know you had to weld them. LMK later Clint

 

The heavily worn plate in the photo has less than 2K miles.



This picture shows the position of the two rockers twisted a bit. This guide plate has the minor wear spots and you can see that the rollers are not centered on the valve stem. 2000 miles here too.

 

Interesting. So the Isky guideplates are heat treated too? Also, do the PRs fit tighter in the slot on Iskys than GMPP? And, what about the depth of the slot? On my GMPP ones, I had to grind out a little but since the PRs were touching the guideplate.
How do you line up the Isky guideplates?

Excellent topic BTW.

Isky guideplates would make a great winter screw-around type project- cheap but time consuming.

 

Ya got to tack weld them on the head after getting them aligned. Then pull them off and weld them and grind.
If ya grind on these things it takes the case hardening out,then there is not much heat treat left.
The fit is what it is and about .025 is normal.

 

Well for ****s & giggles I set up a dial indicator jig to see how much adjustment you can get by shifting the GM guideplate side to side to get the best possible alignment.

You can only shift it .015" either direction with 7/16 studs. That does not add up to any kind of adjustability factor. I really dont see how spending lots of time getting the guide plate positioned where you want it can really help with this small of range.

Also considering that when you do get the slight wear in the groove there goes all your hard work.

Unless a GM guide plate is defective, I honestly believe that throwing the plate on is the same as taking extreme care to position it where you want using that .015" range.

The problem is the damn things are not hardened. This has turned into the most simple most complicated damn thing I have seen in a while. It aint rocket science.

Oh well, on to the good news.
We have sucessfully quadruple case hardened a single plate and it shows signs of being much harder than before. Before the process a file would easily cut into it and now it wont. Even the sound of the file is entirely different than before.
So tomorrow I will have all the new ones done the same way. This is most certainly going to help with the wear problem.

 

A few weeks ago I looked at my valvetrain (same as yours).
All 16 guideplates were almost as worn as the one in your photo.
I did not check valvetrain geometry then (used 7.200 PR). I did check
it now and it turns out I need 7.100 PR ( ).
So I put new guideplates and 7.100 PR in last weekend, but I have a
feeling it may not help.

 

You are lucky you did not lose a valve like I did.

 

.....

 

I think we need a picture of properly adjusted rocker on here. So we can all get an idea of what to look for. Anyone have one? I have don't have any pictures of mine.

All I know is that .015 made a huge difference from hitting the rocker body and hitting the center of the roller tip.

 

Ya don't need a picture it's just common sense. Get everything square and true and not in a bind.

 

Well I took my valve covers off and started checking things and the alignment is not too great with the the valves and rockers. I have the GM guideplates with Comp pushrods and 7/16" studs and I am going to wallow the holes out a little to see if I can get the alignment much better. I am running Trickflow heads so it's not just you guys having trouble. I'll let you guys know how it works out. Later Clint

 

I will go one farther in that nothing on a mod or build is a bolt on and needs to be checked and rechecked.
Most people today want that "instant" stuff and mechanic's(with DEALER mentality=flat rate) and those that throw it together don't do well in racing.

 

Ya need the Trick Flow Plates.

 

There was a post that said the GM and trickflow plates were the same thing from somebody who works for Trickflow? I would buy them but read there is no difference. LMK Later Clint

 

You all just need to get ISKY's ... They are by far the best.

Have you seen anyone on here complain about them? So you have to tack weld them ... Big deal?