[Fot] oil supply to the valve gear of a TR-4

[Greg Solow]

I you have a stripped block, and you look down the oil hole drilling from 
the rear main bearing that goes to the rear calm bearing bore, you will see 
that there is a manufactured in restriction in that hole right near the main 
bearing. I can't tell you the exact size, but I think it is around 1/8" or 
so. The rest of the drilling is larger than 1/4".  So this is the hole size 
that meters oil to the cam bearing.  I grind a groove with a die grinder 
that has a 1/4" ball  burr on the end. I try to go about 1/8" deep and 3/16" 
or so wide into the iron of the block.
    If by chance you get to much oil flow to the head, you can meter this by 
installing a jet into the horizontal hole in the head that has a bolt 
plugging its open end on the rear of the cylinder head.  You can remove the 
bolt, tap the hole and screw in a plug with any size hole in it you wish. So 
this can be done with the engine installed in the car and the head on, if 
the drilling and tapping is done before hand.  I drilled one head to accept 
Holley main jets as metering plugs. I have never had to make use of this 
feature.
                                                                             
    Greg Solow