Pump shimming

[Dagnuten]

think about it this way, with more pressure it will not only fill the injectors faster, but will have more fuel pressureized in the injector, helping it to spray right.

and it's not really a crank-it-as-high-as-it-will-go scenerio, but international specs say the fuel pressure should be at 68psi to be running correctly. My truck when putting the fuel gauge in was at 42... but I've had the regulator stuck and it burned out my pump, I think the spring, regualtor itself is shot. Anyway, when shimmed, I gained throttle response and my sotp dyno said I had better acceleration. I figured thats because it was set so low in the first place, before the shim it would starve for fuel when I floored it.

I still got problems though, I think my regulator is sticking or something because I jump form 60 to 70 psi at idle and can drop to 30 for a second, then jumps back up at wot. More to play with...

[Ramsmoker]

Your absolutely right on the pressure. Injectors are multipliers so if the pressure going in is higher, the pressure coming out will be higher. I was never happy with the stock regulater even with a total rebuild. Mine is real steady with exturnal reg. and that could be due to the larger diaphram.

[cebulmer1]

Just be careful with the pressure (LOL), it doesnt like to much!!!(LOL)