hello my name is darreni have a toy you might find is funmy ride is a mazda b1600 pickup \ r33 gtr skyline \ toyota ????im using 1000 cc injectorsHKS stage 2 cams custom turboms123 toyota diff2 2jz intank fuel pumps and 1 wallbro 256.lph externalI STILL HAVE NO FUEL PSI OVER 60% THROTTLElast dyno was 450 wheel HPplease helpthank you [IMG][/IMG]
Modified by dantos at 1:22 PM 1/7/2010

Moved to Hybrids

I am pretty new to car building so forgive me if this is stupid. is your fuel pressure boost referenced to increase psialong with boost. wondering if at 60% throttle you are getting enough boost to partially overcome the injectors and not enough fuel is spraying in.

how do you know you have no fuel at 60% throttle.do you have a fuel pressure gauge? or is the car stuttering when the throttle is opened up that much.

also is that 60% smashing the pedal to the floor(accelerating hard)or driving steady with the throttle open 60%?

why so many fuel pumps. the one walboro should have been enough for that amount of horsepower?

450SX! wrote:I am pretty new to car building so forgive me if this is stupid. is your fuel pressure boost referenced to increase psialong with boost. wondering if at 60% throttle you are getting enough boost to partially overcome the injectors and not enough fuel is spraying in.

how do you know you have no fuel at 60% throttle.do you have a fuel pressure gauge? or is the car stuttering when the throttle is opened up that much.

also is that 60% smashing the pedal to the floor(accelerating hard)or driving steady with the throttle open 60%?

why so many fuel pumps. the one walboro should have been enough for that amount of horsepower?

If he's using the stock RB20 FPR it's boost referenced. If I was running a decent amount of boost I would upgrade though. The 255lph in-tank pump has been proven to be reliable up to 450 lots of times. I assume the inline version would be pretty similar. I would definitely lose that odd pump configuration. I'm thinking each pump is wired up to the same relay or something. That will kill the power availability on that circuit. Each pump needs it's own hot lead and relay IMO. Troubleshooting wiring from the bench is rough, especially given the vague description.

WD

no all pumps run 12v direct on 6wg low boost 25 psihi boost 36 psimax boost 41 psi turbo (boom)elect fuel psi gauge in dashsoft acceleration no problemshad 2 Aeromotive fuel pumps it lasted 6mot each

just got rb 30 block sent to rebuild to 5.3 literneed to fix fuel prob firstAeromotive fuel not for every day driving to exp to change every 6 mot

Rex wrote:Moved to Hybrids

sorry wrong place thank you

just busted my lsd will get a new one later

depends on the pump, some are advertised as not being for street use.with aeromotive they also suggest their voltage regulator to help increase the life of the pump.

your fuel pumps should have fuses in line between them and the batteryas well as a relay.6awg can carry a lot more than those pumps need. My aeromotive A1000is meant to be used with 10awg according to them and for daily driven use. the walboro only needs 20 amps to produce 140psi of pressure. http://www.inlinefuelpumps.com....jpg

Something I read about quite some time ago was the cooling benefit of the in-tank pumps. I know it's stupidly obvious, but I've read alot of horror stories about using in-line pumps and having them fail. Mostly because they just aren't designed for the prolonged use of daily driving.

The best setup I came across was dual in-tank 255lph pumps. They supported 767whp on a 351 that was running quite a bit of boost. In singular form they have been proven, as I've already said, to easily and reliably support 450whp on 2 liter applications running boost in the 20's.

One thing I'll note. You don't need 100lb or 1000cc injectors when you're only making 450whp. I can make that much with 550's. Larger injectors are harder to control and unless required, simply aren't a good choice. Neither are 3 fuel pumps when a single DOES work just fine.

The problems I see are 100% operator error.

WDRacing wrote:Something I read about quite some time ago was the cooling benefit of the in-tank pumps. I know it's stupidly obvious, but I've read alot of horror stories about using in-line pumps and having them fail. Mostly because they just aren't designed for the prolonged use of daily driving.

The best setup I came across was dual in-tank 255lph pumps. They supported 767whp on a 351 that was running quite a bit of boost. In singular form they have been proven, as I've already said, to easily and reliably support 450whp on 2 liter applications running boost in the 20's.

One thing I'll note. You don't need 100lb or 1000cc injectors when you're only making 450whp. I can make that much with 550's. Larger injectors are harder to control and unless required, simply aren't a good choice. Neither are 3 fuel pumps when a single DOES work just fine.

The problems I see are 100% operator error.

i am not getting enough fuel flow from one pump i have planty presher from one pump i looking at getting 900+ hp (1000cc injectors) rb20 is test engas rpm goes up psi drops because flow drops (6awg for test only)

Well you have much to learn if you're aiming for 900+ and you're practicing on an entirely different motor...

I don't know what your problem is. Either the pump is bad, there is voltage loss under load or there is a restriction. The single 255lph pump will easily support 450whp, that's just fact man. I thought you were using 3 pumps anyway? If it's losing fuel flow under a load then something is wrong. Only 3 things I can think of, voltage, defective pump or a restriction somewhere up line from the pump.

Do you have the in-tank pumps pushing through the in-line pump?

WD