Went to the dyno today. Gained 24rwhp/19ftlbs at 8600 rpm. We never ran it up beyond that.

At 8600 the Walbro 255hp is taking a dump. This is the second one to fail on me. Fortunately I was on the dyno when it started failing.

Add to that a need to upgrade to RC1000 injectors. I need a reliable adequate fuel supply delivered at the correct pressure.

What to do? Dual pumps? Booster pump? Aeromotive pump? Voltage booster? New larger fuel lines? New tank?

If you have tackled the inadequate fuel supply issue, please tell us what you did. Pictures would be nice.

Thanks in advance.

Update 3/16/08

It turned out not to be the pump but the small hose clamp used in the tank. It was loose when I pulled the pump. ponder2.gif Every time I turned the screw it would pop internally and loose tension.

Diagnosis: A bad hose clamp. banghead.gif

It was recirculating the gasoline in the tank and not putting out the pressure needed. rolleyes.gif

I went down to the marine hardware store and picked up some new hose clamps that are far stronger appearing.

The pump is apparently still good.

 

i would say go twin walbros, what size injectors are you using now? you said u gained 24hp and 10ftlbs, what was the original number?

 

Currently running RC 750s. Those gains were at 8500rpm, a 1000 rpm prior to my previous session and yet stronger.

I'm considering the Bosch 044 inline as a solution to this problem. I want to go away from the Walbros. They are obviously not up to the task in my estimation.

 

my tuner ran into the same problem... he is going to see if a inline pro fuel rail and a Booster pump is going to help my fuel problem...

 

i meant what hp and torque are you making now? 500?

 

Close but not quite. With a little fuel I expect 300 torque and over 500 rwhp.

 

I have been researching this problem as I expect to be using 1000cc
injectors and I think fuel delivery may be a problem. I looked at the flow rates and pressures, injector duty cycles, etc. The Walbro and the Bosch are actually very close in delivery. Short of going with a Weldon (big $) Airmotive is gravity, I am going to use an intank Walbro with another inline Walbro and upgrade the pressure line (-8) and leave the return alone. Increase flow of 30-40% . I've been told by a respected tuner this setup is good to high 600whp setups.

 

I just pulled my tank to sump it and go with the a1000 ill snap some pics today of the subframe removed for you so maybe ypu can get some creative ideas

 

you only have a couple options... you can use an intank walbro... then from there run a -8 or -10 line with a inline walbro or bosch 044. Next option is to sump the tank. from there i would run a -10, if you want to run a aeromotive pump i would not get the a1000 although it is rated high, it does not support too much power, The eliminator supports much more. Weldon pumps are a lot of money but work great. The best option which i had done on one of my previous cars was I sumped the tank, ran -10 line with a Y then put two bosch 044's. then another Y and ran that line straight to the fuel rail. or you can run a dual sump, and two -10 lines then the two pumps then a Y into a single -10. No matter what once the walbro starts to lose fuel pressure on higher HP dyno pulls, you are running into big money. You have to run pre and post filters also. Here are a couple pics where i got my ideas from when i did mine.

 

s2k has its fuel tank above the diff so its a tad tricky. im just awaiting Full Race sump kit to have it welded on and ill post pics