Fuel pressure = zero when dumping clutch
07-18-2011, 08:07 PM
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Fuel pressure = zero when dumping clutch Hi,
I went to the track yesterday. Current setup is a Walbro 255 in-tank with hotwire kit. When I dump the clutch, front end goes high up in the air and fuel pressure goes down to zero. I tried tank 1/2 full and 3/4 full and see no difference. Voltage is good 13.2-13.6v. I think the demand is too great for the pump. What do you recommend? Dual setup? 1/2'' line with pressure regulator + return? Baffle needed in the tank? Every time I shift gears, pressure goes down to 50-55 psi. Systems is leak free I think, pressure stays at 45 psi when key off and 63-64 psi when pump on at idle. Killer set-up or solution needed
Want this bumper to touch the ground! Stock fuel line by the way
Thanks
I went to the track yesterday. Current setup is a Walbro 255 in-tank with hotwire kit. When I dump the clutch, front end goes high up in the air and fuel pressure goes down to zero. I tried tank 1/2 full and 3/4 full and see no difference. Voltage is good 13.2-13.6v. I think the demand is too great for the pump. What do you recommend? Dual setup? 1/2'' line with pressure regulator + return? Baffle needed in the tank? Every time I shift gears, pressure goes down to 50-55 psi. Systems is leak free I think, pressure stays at 45 psi when key off and 63-64 psi when pump on at idle. Killer set-up or solution needed
Want this bumper to touch the ground! Stock fuel line by the wayThanks
07-19-2011, 06:34 PM
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Discovered tonight that the alternator stud was loose. Aluminum melted on treads because of bad connection!!! I think that's a part of my problem.... The accesory belt was almost off the binder pulley too!! I supposed that the alternator was trying to increase voltage and it was overloaded. Maybe that's why 2-3 mph were missing in addition of lack of fuel pressure.
Now it's time to repair and go back to the track to try again!!
Now it's time to repair and go back to the track to try again!!
08-07-2011, 11:03 AM
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Finnaly, still have the same problem even if electrical is ok I reinstalled a new Racetronix pump with stock bucket unmodified and ventury also new fuel filter is in. Have hot wire kit too. Pressure is 60-62 psi normal condition. When I dump the clutch, pressure = zero as soon as the car leaves the line. At top end, pressure = 50 psi and the car is lean around 13.6-13.8 I think it's time for a dual set-up 
Are stock line with pressure regulator in-tank ok for a dual set-up? Baffles in-tank needed (car is a 2002 camaro) Do you think the big pressure drop is related to pressure regulator reaction time or location? Car is around 550-600 rwhp
Lonnies, do you ship in Canada?
Thanks for your help
I reinstalled a new Racetronix pump with stock bucket unmodified and ventury also new fuel filter is in. Have hot wire kit too. Pressure is 60-62 psi normal condition. When I dump the clutch, pressure = zero as soon as the car leaves the line. At top end, pressure = 50 psi and the car is lean around 13.6-13.8 I think it's time for a dual set-up Are stock line with pressure regulator in-tank ok for a dual set-up? Baffles in-tank needed (car is a 2002 camaro) Do you think the big pressure drop is related to pressure regulator reaction time or location? Car is around 550-600 rwhpLonnies, do you ship in Canada?
Thanks for your help
08-07-2011, 08:39 PM
#6
Yes I ship to Canada....
You have to take into account the G-forces acting against the fuel system under hard acceleration. This works against the pump when you launch the car. The rear mounted regulator is not helping you compensate for the pressure loss either since it is in the tank.
Also at 550-600rwhp, the single pump is already at its limits, even when the car is not moving.
Feel free to call if you want to discuss in more detail.
You have to take into account the G-forces acting against the fuel system under hard acceleration. This works against the pump when you launch the car. The rear mounted regulator is not helping you compensate for the pressure loss either since it is in the tank.
Also at 550-600rwhp, the single pump is already at its limits, even when the car is not moving.
Feel free to call if you want to discuss in more detail.
