Saying a claimed HP and doing a claimed HP are two different things. You need to look at all the things I said before to find out if its truley the pumps or you have something else going on. Do you have a hotwire kit on the truck? Even my 420 pump did nothing until I changed the wiring to the fuel pump with a booster wire to add the right voltage to it. From there it was golden.

Rick

 

I appreciate your help Rick, but the only thing that you said before was to get a Bosch pump. Based on that and everyone else's replies, I went ahead and ordered a Walbro 255 in-tank kit. Is there a problem with the stock wiring not supplying enough voltage to the pump? Can I just power the pump with a relay that the stock pump wires energize, and then run a fat wire from the relay to the pump? Thanks.

 

 

pretty much, or you can buy a F-body racetronix hot wire kit and run with that.

Rick

 

New pump fixed it. Now comes a lot of tuning to get rid of the excess richness I kept adding to make up for a weak pump. Thanks for all replies.

 

Cool, where did you get the kit? And, did you reuse the stock wiring?

 

Texas Speed and Performance (Do I get a partial refund now, Brian?). The wiring is stock still from the tank to the fusebox, I have no fuel pressure drop whatsoever now (still running the MagnaFuel inline). The pigtail that they sent with the kit doesn't plug into the stock plug, I removed both plugs and butt-spliced it. That is probably what was intended, the instructions don't really apply to trucks. All of the information I needed to install it is on this forum. They sent a piece of fuel line, I didn't need it. I cut the very end off of the stock plastic line and hose clamped it to the pump.