getting a mild build: vortec heads, intake, mild 298/298 duration cam. with the 5.7 injectors, which pump should I get? Is the 305 tpi pump enough, or do I need a walbro 190?

 

Either one should work. Dont know what the flowrate is on the TPI pumps, but I would imagine that at around 14-20 PSI, it should flow enough.

 

I'd go with the Walbro so you have no worries later on if you need more fuel. Dropping the tank is alot of work. I'm running the Walbro 255.

 

I am currently using a pump from Harris Performance. It's 255pph which is ~40psi @ 12v. It is under $100 shipped.

 

I would think a 255 is overkill if I would be running around 20 or 21.

 

I would recommend a Walbro 190lph pump. This pump at TBI fuel pressure can support ~450hp and you will have no prob getting the fuel pressure down like you would have if you threw a 255lph pump in your tank. (assuming your running around the stock fuel pressure) If you plan on bumping the FP up to upwards of 20psi+ then I would suggest a 255lph.

 

Doesn't the tbi have a return style FP setup? I always thought that the regulator cut it off at the predetermined PSI and just returned the excess to the tank. I could be wrong though.

 

That is true. However the return line for the TBI setup is designed for the stock pump flowing ~13 psi. With a 255lph pump in the tank so much fuel is being deferred to the return line that it cant keep up with the pump, raising the overall fuel pressure of the system. In short, the return line is too small for the 255lph pump at stock fuel pressure.

 

is it too small with a 190? and is the feed line ok?

 

190lph pump is much more practical for a tbi setup

 

I got a 190 for sale. In car right now, but bird is going on the choppin block real soon.