Let’s Tune This Engine

RE-check all clearances and valve train geometry,
you don,t bend push rods unless your having clearance issues someplace
it might be a clearance issue like,
the rocker slot binding on the rocker stud momentarily
or the spring binding at full lift,
rocker under side contacting retainer,
retainer touching valve seal,
rocker lock nuts contacting inside of rocker,
have you checked piston to valve clearance!
pushrod rubbing on guide plate or slot, in heads, etc.
you should not hear metallic clicking if theres zero clearance issues,
once valves are properly adjusted
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I would agree with you there. I have a hunch too. Not new plugs but they looked good. Wires are a couple of years old.
Once you have the valves adjusted, I think getting the ignition sorted will smooth it out!
I do agree with grumpy, might be wise to do some valve train geometry checks! With a different cam and new type of cam(roller) your geometry may be different!
Will do. I did check the geometry, but I’ll check again.

In fact, that is something that I can do while I wait for the new pushrods: check the geometry with straight rods. It did look spot on the last time I checked.
I pulled out all the spark plugs so that turning over the engine would be easier.

With the pushrod length checker, I checked cylinder 1. That’s where the banana-ed pushrod came from; intake side. The geometry was still spot on.


There was a ding in the rocker, but not in the cup itself.
Once thé pushrods are here I’ll do the EOIC method and add 1/2 a turn... and not forget the setting screw :confused:

Will also need to check this guide plates. I wonder if there is contact there.
it takes hundreds of pound exceeding normal operational stress to bend a push rod,
Id be looking for the reason,
it bent and that concerns me far more than the state of tuning.
Hmmmmm. I guess I need to put this back together and see what happens. Hopefully it’ll run ok. If not, I’ll dig deeper.
Hmmm. I’ll do a compression test on that cylinder. That should tell us if the cylinder slapped into the piston.
check spring bind , retainer to valve seal, and rocker slot to rocker stud and rocker slot to rocker nut clearance
you bent a pushrod somethings got a clearance issue
The rockers I have are these double rollers


Nonetheless I’ll check them all for signs of contacting.
You might not have had the rockers off the studs, but make sure that the recess for the
polylock is up. I made this mistake before I realized there was a difference.

Yeah. I was lucky I noticed those when installing. however, if I forget to tighten poly-locks... I can certainly screw this up too.
Those pushrods in your picture are the WORST ones to have. They have pressed-in ends. And they snap off with the smallest problems.
You want one-piece formed pushrods.

Aw shit !!!! Thanks for flagging. I thought being a good brand... will replace them.
check spring bind , retainer to valve seal, and rocker slot to rocker stud and rocker slot to rocker nut clearance
you bent a pushrod somethings got a clearance issue

I have to fully agree with this statement.
Is there a way to do that on the car ?

My guess is I don’t have tools necessary to do that.

I do know that these heads can take 0.650 lift. The comp cam coils that are on there can take similar.
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