Stock Regulator no good?
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From: Fort Lauderdale
Stock Regulator no good? First of all, my specs:
Forged LS1, but stock heads/cam
Headers->Turbo
Walbro 255 in tank
Mototron 60lb inj
Did a fuel flow test after the pump install and came out to support ~900FWHP
Went to track last night and had some major leaning issues with only 6lb boost. Strange thing is, in 2nd gear I had no lean prob and no knock retard. In 3rd gear I had a very lean condition above 4800 and knock, and my advance was like 14 degrees! I know 3rd gear is where you get true load so I was concerned. So I went into Edit and richened up the table above 5000rpm. Did a run and same thing...
Strange
Then I thought, let me look at my Fuel Pressure. SO I watched it and my friend watched autotap. In 2nd gear no probs, then in 3rd gear no probs UNTIL 5200 RPM the FP Guage jumped from 55-60psi to 20psi in a split second.
No wonder why the car was running so bad
So I am assuming its my regulator...any comments? Good thing I ordered the CAS from ls1speed on Monday so it should be here any day...
Forged LS1, but stock heads/cam
Headers->Turbo
Walbro 255 in tank
Mototron 60lb inj
Did a fuel flow test after the pump install and came out to support ~900FWHP
Went to track last night and had some major leaning issues with only 6lb boost. Strange thing is, in 2nd gear I had no lean prob and no knock retard. In 3rd gear I had a very lean condition above 4800 and knock, and my advance was like 14 degrees! I know 3rd gear is where you get true load so I was concerned. So I went into Edit and richened up the table above 5000rpm. Did a run and same thing...
Strange
Then I thought, let me look at my Fuel Pressure. SO I watched it and my friend watched autotap. In 2nd gear no probs, then in 3rd gear no probs UNTIL 5200 RPM the FP Guage jumped from 55-60psi to 20psi in a split second.
No wonder why the car was running so bad
So I am assuming its my regulator...any comments? Good thing I ordered the CAS from ls1speed on Monday so it should be here any day...
definitely the first thing i would do.. you could also check the voltage to the fuel pump, and go ahead and run a relay right off the alternator to it for more voltage... even with that though i dont see how one pump was calculated to support 900fw.. i would stop at 700 fw on one pump.
Thread Starter
TECH Enthusiast
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From: Fort Lauderdale
When I installed the Walbro I ran 12 guage wire through fuse from the battery to the tank. Used a relay and wired it in so the stock pump wires trigger the relay.
Then I did a volume flow test off the rails and it pumped about 8lbs of fuel(or about a gallon) out in 1 minute...
Spoke with a sales rep for Delphi over phone and we worked out the 900HP number from a forumula he gave me and he said that sounds about right for that weight of fuel....
Then I did a volume flow test off the rails and it pumped about 8lbs of fuel(or about a gallon) out in 1 minute...
Spoke with a sales rep for Delphi over phone and we worked out the 900HP number from a forumula he gave me and he said that sounds about right for that weight of fuel....
Originally Posted by MIGHTYMOUSE
definitely the first thing i would do.. you could also check the voltage to the fuel pump, and go ahead and run a relay right off the alternator to it for more voltage... even with that though i dont see how one pump was calculated to support 900fw.. i would stop at 700 fw on one pump.
Pulse Dampener. Just keeps the injectors' pressure pulses
from making any jiggy pressure waves in the tubes that
might dither around the shot delivery.
The regulator is back in the tank. As I understand the late
model fuel lines, the feed comes up to beside the engine and
from there spits to a rail feed hose and the return line to the
reg. So all forward drop up to that point, from flow losses and
so on, should be nulled (kept in regulation).
Huge pressure dropoff seems like it would have to be a fuel
line, fuel filter or fuel pump power supply problem. Can't see
the regulator suddenly opening up, with -less- return flow
needed. But once return flow goes to zero (injector demand
exceeds supply) all bets are off, for pressure. Seems like a
supply-side problem.
Why 3rd is any different than 2nd is a mystery.
from making any jiggy pressure waves in the tubes that
might dither around the shot delivery.
The regulator is back in the tank. As I understand the late
model fuel lines, the feed comes up to beside the engine and
from there spits to a rail feed hose and the return line to the
reg. So all forward drop up to that point, from flow losses and
so on, should be nulled (kept in regulation).
Huge pressure dropoff seems like it would have to be a fuel
line, fuel filter or fuel pump power supply problem. Can't see
the regulator suddenly opening up, with -less- return flow
needed. But once return flow goes to zero (injector demand
exceeds supply) all bets are off, for pressure. Seems like a
supply-side problem.
Why 3rd is any different than 2nd is a mystery.
