Oh okay so no need to really do that then. Are the cylinder heads interchangeable through out 01-04.5 on the Lb7

01-04. and yes

Okay ill be getting my heads done soon. What do you think about my fuel Injection Pump? or my Fuel Pressure Regulator?

have you prssure tested the pump?

I think so but im not to certain. What are the stock specs ill be looking for?

Its just really weird. Before we tore down the truck the first time it was running perfect and once we put everything back in and started it up it started running like this.

it should be abel to generate 23kpsi at idle. u can unplug the fpr and watch the rail pressure and what it goes up to.