Aeromotive 340 Stealth Fuel Pump
Joined: Sep 2003
Posts: 3,067
Likes: 7
From: Home of the Rolex 24
Was on the dyno a few days ago and had a similar problem. After my fourth run at 19lbs of boost we noticed it started leaning out slightly after 6500 rpm. We decided to up the fuel pressure because the duty cycles were getting kinda high and the problem got worse. After two more pull where I had to lift off earlier and earlier because my AFRs were rising quickly, the operator did a run with outside watching the mechanical fuel pressure. He said the pressure rose from 45 to 60 but at high rpm would take a dive and that's where I would be lifting throttle. Luckily the motor didn't get hurt but I'm a little puzzled as I thought this pump would support over 500whp. I only made 418 at 18.8lbs. I'm gonna change the fuel filter and fuel pump as I have a new Walbro 400 in my garage and see if the problem goes away. Also I will check the wiring for anything fishy. Also, I was running 1 oz per gallon Protek R and the tank was almost completely full.
[QUOTE=G's 3rd Gen;11004030]What exactly are you experiencing? Falling off under high load or absoluetly no pressure at all?? Explain please.
Fuel pump lost pressure while i was driving, good thing i wasnt under boost. Got the car home and checked the power, filters and frp everything checked out ok, i clamped the return line to try to build pressure wouldnt go above 18 psi.
Fuel pump lost pressure while i was driving, good thing i wasnt under boost. Got the car home and checked the power, filters and frp everything checked out ok, i clamped the return line to try to build pressure wouldnt go above 18 psi.
Hmmm...
http://www.supraforums.com/forum/sho...-charts-review
I noticed on the dyno we had a leaning condition when we got down to 1/4 tank, we attributed it to low fuel now, I'm wondering if it was the pump?
http://www.supraforums.com/forum/sho...-charts-review
I noticed on the dyno we had a leaning condition when we got down to 1/4 tank, we attributed it to low fuel now, I'm wondering if it was the pump?
Installed the Walbro 400 this afternoon and much better. As soon as I started the car fuel pressure was 50psi at the regulator with the vacuum disconnected. Turned it down to 45 and went out and did several second gear pulls, much better. I was going to 10.2 AFRs after 6500! Now I can back to the dyno and tune to 20psi!!!
Thread Starter
Joined: Dec 2005
Posts: 565
Likes: 0
From: YORBA LINDA (O.C.)
So how many Bosch pumps have failed over the years?
The Aero motive has been out how long? I am rolling the dice with mine and If something happens I goes I have a reason to port my block and move to a 500 turbo or soothing in that range.
The Aero motive has been out how long? I am rolling the dice with mine and If something happens I goes I have a reason to port my block and move to a 500 turbo or soothing in that range.
after having my car towed home Saturday night because i lost fuel pressure again for a second time in 3 days, I opened up my fuel pump housing and found that the feed line from the pump to the housing had pop off completely out of the push-lok fitting, pump was pumping fuel back into tank.
I decide to check the hose on the first pump that lost pressure a few days earlier and the hose was lose around the fitting, thats the reason that the pump still had pressure but was only 18 psi, some of the fuel was sipping out back into the tank since hose was lose at the fitting.
Now i just replaced the stock hoses that the pumps came with because they became soft and even started spliting, I replace them with the Gates submersible hoses and when i install them they were so hard to get them on the pushlok fitting that I didnt think they needed a clamp, well after 2 weeks of swaping the hoses they became soft and work their way out of the pushlok fittings, lucky me that both time I lost pressure car was barely under load.
Bottom line I installed clamps and pressure came back, and both pumps are working fine.
I decide to check the hose on the first pump that lost pressure a few days earlier and the hose was lose around the fitting, thats the reason that the pump still had pressure but was only 18 psi, some of the fuel was sipping out back into the tank since hose was lose at the fitting.
Now i just replaced the stock hoses that the pumps came with because they became soft and even started spliting, I replace them with the Gates submersible hoses and when i install them they were so hard to get them on the pushlok fitting that I didnt think they needed a clamp, well after 2 weeks of swaping the hoses they became soft and work their way out of the pushlok fittings, lucky me that both time I lost pressure car was barely under load.
Bottom line I installed clamps and pressure came back, and both pumps are working fine.
Last edited by BLACK MAMBA; Mar 5, 2012 at 09:23 PM.
Also lessons learned, don't go on the internet and report failures of a product until you have eliminated all other possibilities and in this case actually checked the fuel pump.
Thread Starter
Joined: Dec 2005
Posts: 565
Likes: 0
From: YORBA LINDA (O.C.)
If A picture is worth a thousand words......................... Need i say more
looks like ur stealth is just a walbro rebadged but then again what do i know, i dont use it..
looks like ur stealth is just a walbro rebadged but then again what do i know, i dont use it..
