[cbgolz]

I have a 1971 Trans Am with a 455. It is bored .30 over. It is equipped with 1970 Ram Air IV heads. to raise the compression. It runs just great, but after a few minutes of highway use, it starts to click loudly under the valve covers. We have diagnosed that the rockers are not getting sufficient oil flow. Is this because the holes don't line up? Are the head gaskets blocking the oil flow? What do we need to do to get enough oil up to the rockers? Thanks very much for your help.
Craig Golz

[Formulabruce]

Try some rocker arm clips ( deflect the oil down) and get a look at it after warm up while idling.
Did you use hollow push rods?
The screw in plug in the back of the block behind a freeze plug near distributor was or IS installed?
That right there will kill oil pressure up top.
If all thats ok, pull the dizzy and prime the motor with a dizzy shaft on a drill counter clockwise and
see whats going on. Could be you just need adjustment.

["QUICK-SILVER"]

Are those +.030" pistons dished?

If no, what kind of fuel are you running in it?

Detonation happens on projects like this. Sounds like loud valve clatter.

Clay

[njsteve]

You may want to pull a lifter and see if there are oil restrictors installed in the lifter oil galleys. It was a common speed shop modification back in the day (and ruined many a good engine).

I found them in 455HO I was building a few years ago. They look like tiny allen head set screws with a tinier hole in them. If it looks like the galley has threads in it, then they ran a tap in it for installing the restrictors.

Here's what they look like. Those red arrows point them out. Those galleys should be an empty 1/16" black hole and not fitted with a set screw with a pin sized hole in it.

[poncho-mike]

Many engine builders that are not familiar with Pontiac miss the plug that is behind the distributor. One of the things HO Specialties used to sell was oil plugs with a small hole drilled in it to oil the distributor gear. If this plug is left out, you will lose virtually all oil pressure to one bank of lifters, and the other side will be lower than it should. Does one side clatter worse than the other?

[98 SNAKE EATER]