I was at the track today and I was talking to a diesel guy and I was telling hime how my overflow valve was ticking. He told me to put a brass plug in it and drill it out to 50 thousanths or so and therefore holding more pressure for the injection pump and therfore having more top end fuel. Sounded a little fishey to me. Any input?

 

Might work ok for an all out race only set up but i sure would not try it on anything else! You could end up doing a lot of damage to your pump with too much internal pressure due to a wrong guess at that about 50 thousanths hole i would think !

 

Yeah I wasnt to sure. Figured I would ask the experts.

 

A better way to do it would be to shim it. If you put in a new OFV, keep the shims (tiny washers inside) from the old one.

I have the shims in my new one from my old one, and it gives me about 35-40 psi cruising, but still has enough room for the ball & spring to do their job of relieving pressure. I did this to keep it above 15 psi @ WOT on the dyno.

 

Don't do it unless you have a fp gauge, same goes for stretching/shimming the spring.
FP in excess of 40psi is known to blow out internal injection pump seals costing you big money to repair.

 

Thanks for the input!