Fuel supply for a high horse LS

[Stomis]

So this winter Im planning on gearing my truck up for a higher horsepower motor down the road. Ive already got the exhaust beefed up and the next thing other than a t56 behind the LS is getting more fuel to the motor. Right now Im running a standard walbro 255 fuel pump. Its like the go to pump for anything sub 600hp but having more never hurt. Considering I want to move to a 408 or possibly bigger down the road Im really hoping for 700+ at the crank, plus the possibility of dry nitrous will bring up fuel demands.

My fuel cell is currently wired for dual pumps but has anyone ever seen individual pumps ran to each rail? Im thinking I would still need a crossover between the two rails to keep the fuel pressure consistent but I dont think Ive ever actually seen someone not Y the two pumps together.

@Team208Motorsports?

 

[folkenheath]

I have heard of people doing that, never done it myself, I think you are better off running both pumps to a Y in the same line. Then if you want you can setup the 2nd pump to only run above a certain throttle, or RPM, or boost, under a certain fuel pressure, etc. That should allow them to run cooler and last longer. Plus if you wire it correctly, if one of them ever goes out, just swap the wire and now the secondary pump is the primary and you get get home and fix the secondary pump.

If you have high HP demands, then you need to split the line into another Y before the rails, then connect each rail to the same regulator after the rails. If you run them in series then the first rail can potentially starve the 2nd rail fo fuel if you are using really high flow injectors.

 

[bigblock72]

So this winter Im planning on gearing my truck up for a higher horsepower motor down the road. Ive already got the exhaust beefed up and the next thing other than a t56 behind the LS is getting more fuel to the motor. Right now Im running a standard walbro 255 fuel pump. Its like the go to pump for anything sub 600hp but having more never hurt. Considering I want to move to a 408 or possibly bigger down the road Im really hoping for 700+ at the crank, plus the possibility of dry nitrous will bring up fuel demands.

My fuel cell is currently wired for dual pumps but has anyone ever seen individual pumps ran to each rail? Im thinking I would still need a crossover between the two rails to keep the fuel pressure consistent but I dont think Ive ever actually seen someone not Y the two pumps together.

@Team208Motorsports?

Dual fuel pumps can be a headache to plumb.

I like this pump for high horsepower setups. http://walbrofuelpumps.com/walbro-f90000267-fuel-pump-e85

They have been quite reliable but require good wiring and connections to support the 15 or so amps they draw. On street driven cars I set them up with a resistor to drop the voltage to around 10.5 volts (4-1 ohm 10 watt resistors in parallel epoxied to a heatsink) and a second relay to bypass the resistor that is wired to come on at WOT or 2-3 psi of boost.

 

[Stomis]

I have heard of people doing that, never done it myself, I think you are better off running both pumps to a Y in the same line. Then if you want you can setup the 2nd pump to only run above a certain throttle, or RPM, or boost, under a certain fuel pressure, etc. That should allow them to run cooler and last longer. Plus if you wire it correctly, if one of them ever goes out, just swap the wire and now the secondary pump is the primary and you get get home and fix the secondary pump.

If you have high HP demands, then you need to split the line into another Y before the rails, then connect each rail to the same regulator after the rails. If you run them in series then the first rail can potentially starve the 2nd rail fo fuel if you are using really high flow injectors.

Hmm mm I see what you mean.

 

[Team208Motorsports]

Run single large enough pump and done. There are plenty of large intank options. Don't add complexity too the lifeblood of your engine, unless you want to keep rebuilding that engine.

 

[bigblock72]

Run single large enough pump and done. There are plenty of large intank options. Don't add complexity too the lifeblood of your engine, unless you want to keep rebuilding that engine.

x2

 

[RootBreaker]

it took me to turn 43 to finally say... do it once, do it right, pony up and dont look at the expense as any other way costs more and creates headaches...

 

[Stomis]

It was always in the plans to do dual pumps when I built the fuel cell. But then again the options for a single pump supporting 800hp in tank were pretty astronomical 2 years ago.