jgiachino

Does anyone with the GDP Perfromance System Kit have an issue with the last 1/4 tank of fuel? I've seen some posts on here where people have to fill up at 1/4 tank in order not to run low / starve the motor.....

I want the gdp so i can safely turn up my smarty and keep good pressure....but i'm one of thoses that always has 1/4 tank or less in the truck....I want it to work like stock....is that possible with the GDP 392?

If the answer to the above is no way to replicate stock....is there anyway to run a switch that works the 392 or the stock in tank pump? I suppose as a worse case, you just switch to the stock pump to use the last 1/4 tank??

Thoughts?

Dang

I have found that my FP gauge bounced around when I going down a steep decline or I come to abrupt stop when at or below 1/4 tank. I called Richard at GDP about this and he said that since they only have one baffle in the tank, the fuel will slosh around pretty good and you will get "bounces" in your reading below that mark. If you stay on flat gound, you will probably be fine below that mark, for a while.

wap

I run down to an 8th and then much less than that and like Dang said my FP guage will bounce around from about 20 down to 10, wich is still higher than stock but then I know it is time to fill up.

I did the vent mod at the same time and now even with 1/4 left in the tank it will still hold about 30-33 gallons.

On mine if the GDP will not pick up the rest of the fuel I can crawl under the truck and swap the conections from the GDP to the stock pump and get the rest of the fuel out, but this would only be for emergencies. It would be easy but not as easy as flippin a switch.

skynyrd

its not the pump that causes the issue its when you replace the pick up tube in the tank it you try to keep the pick up tube to pretty much stock and cut the tube at like 22.5 degree instead of 45 and as close to the bottom it helps some. i get my fuel pressure gauge bounceing around at about a 16th of a tank. but that only happens during braking and right turns.

RamNu2

You guys all seem luckier than me my guage holds around 6psi until half tank then drops to 0 when I come to a stop or take off the truck just falls on its face then slams you into the seat when it picks up again. I am going to call Richard again today.

Dang

6 psi? The 392 should come with a factory setting of about 17psi. Did you change the settings on the regulator?

jgiachino

Talked to Richard today (nice guy)....he said factory setting is 17-20psi....and that i should cut the bottom of the pu tube per instructions...but that the lack of baffels in the tank design does cause some minor issues at low fuel levels....

Also said that if you follow the install instructions for the perfromance kit (not for the competition kit), you can add a switch to alternate between the gdp and stock....this would give a work around for the low fuel issue....

Snoxracer

I used the plastic tube and cut it at a little bit of an angle (touching the bottom of tank behind orginal in tank pump location) and don't have any problems now. But I was having problems when the tank was below 1/4 and I was still running thru the stock pump.

RamNu2

I switched guages when I spoke to Rich and my psi is actually around 20 untill I decide to up the ante then it drops down to about14-17psi.

jwb600

I try to keep mine around 1/4 of a tank or more. ive been told its hard on any pump to run the fuel low all the time

06CTDforAU

I've heard that and that is also what I have been told. I just ordered a GFS-392 Comp System. I hope it works out good for me......

jwb600

it should. thats what I run. if you have ever heard a fass pump and the noise they have, this is nothing like it, very quiet and mine has worked great since it was installed. I would buy the system again. I also have the big line kit