Adding powerdyne SC to my 5.3 truck. Fuel pump holds 61 lbs and injectors running at 70% of capacity at WOT . Will be running 10 pounds boost Max. Think I need a a fuel pressure regulator or will I have enough fuel as is?

 

You will need a boost referenced regulator so that when boost rises so does fuel pressure to compensate. Look at it this way, Under boost the injector tip will also see that pressure. So if you have 10lbs of boost on the tip of the injector, You'll have to increase incoming fuel pressure a like amount to make the injector put out the same amount of fuel as it did when not under boost.
Basically boost tries to push fuel back into the injector if you don't do something to compensate for it you'll end up running lean.

 

Are you saying n/a it runs 70% duty cycle on the injectors ? Or it does with the blower ?

Boost referencing can give some extra capacity, as long as the pump also has more capacity left. And when you need bigger injectors, you'll still need bigger injectors anyway.

If you are only going to run 10psi and never more, I'd just spend the money on larger injectors and/or a better pump as needed. With 61psi base and 10psi boost on a stock style un-referenced setup, that still leaves 51psi of actual fuel pressure across the injector which is fine.

 

Thanks for the replies. Been working doubles so have not had a chance to respond.

I get 61 lbs and 70% of duty cylcle without the blower at WOT.

This is a 2005 so it is "returnless". Adding / changing the pump and or regulator means lifting the bed or dropping the tank.

 

You don't need to boost reference as long as you have enough injector. If the pump holds 61 PSI, you will effectively be at 51 on 10lbs boost, which is enough.

 

IMO try it and see, or just fit larger injectors and try it and see. If the pump struggles, stick a BAP on it.

Means you dont need to touch the tank.

But either of those options will be perfectly fine.