fuel pump assistance from anyone please

**01blackbird** · 04-26-2008, 08:01 AM

I'm looking to upgrade my in-tank fuel pump to at least 240 LPH or higher. My T/A is a 2001 returnless system. I'm being told that there is not one on the market, that the ones being sold for LS1 f-bodies are only good for the 98-99 cars that have a return fuel system and the 2 different fuel systems require different type of pumps (the way they are processed). Can anyone shed some light on this, any sponsors with some insight? Thanks for any help.

**0rion** · 04-26-2008, 09:17 PM

you were told wrong. 98+ f-bodies all have a returnless system. The main difference is in the tank and pump itself. The 98's use a metal tank that has baffles in it, the 99+ f-bodies have a plastic tank and the pump is in a bucket with a venturi feed. The only return systems that I'm aware of were on the vettes.
You may check with Matt at Harris Speed Works and see what they have to offer pump wise. I have the racetronix kit in mine that I *thought* was a 255L/hr walbro but after looking at their site I see they state it's a 235 L/hr @58psi. The kit is PnP compatible with the msd pump boosters so that's an option too.
Here's a link to the racetronix kit for the 99+ f-bodies. I highly recommend the kit, it's a great kit and racetronix has done their homework on it. The install instructions were great.
http://www.harrisspeedworks.com/shop...cat=330&page=1

**mrr23** · 04-27-2008, 04:26 AM

i have the walbro 255lph intank pump and the racetronics hot wire kit. the person you spoke with was told incorrect.

**01blackbird** · 04-27-2008, 08:08 AM

Thanks for the input guys. It's been a few years since I've had a 98 or 99 fbody in the shop to work on and I couldn't remember thier fuel system set up so I was taking his word on it.

**01blackbird** · 04-27-2008, 08:17 AM

Originally Posted by mrr23

i have the walbro 255lph intank pump and the racetronics hot wire kit. the person you spoke with was told incorrect.

Let me ask you this, do you have the low or high pressure pump that is offered by Walbro? And what is the hot wire kit all about? Is that to keep higher voltage to the pump instead of the varied voltage? Thanks.

**0rion** · 04-27-2008, 02:08 PM

The hotwire kit goes directly to the back of the alternator to keep the voltage up, so yes. I'm gonna have to look at the pumps again because I could've swore that the racetronix kits had the 255l/hr pump but HSP's site says differently.

**01blackbird** · 04-27-2008, 06:07 PM

Do any of you guys have any issues with too much fuel pressure running these hot wire kits? It seems like at idle or at lower speeds where fuel pressure demand is low that it would be too much.

**0rion** · 04-27-2008, 08:06 PM

your regulator should keep that from being an issue.

**mghawk57** · 04-28-2008, 04:03 AM

Does a 2002 Trans Am have a returnless system and/or a fuel pressure regulator?

**0rion** · 04-28-2008, 07:08 AM

Originally Posted by mghawk57

Does a 2002 Trans Am have a returnless system and/or a fuel pressure regulator?

yes, returnless system with a regulator in the tank.

**mghawk57** · 04-28-2008, 08:17 AM

Thak you - I've got that answer now 3 times - must be right - should have asked
here 1st

**01blackbird** · 04-28-2008, 03:43 PM

Originally Posted by 0rion

your regulator should keep that from being an issue.

Your making me feel better about it, thanks. I was e-mailing one of our sponsors (neweraperformanceparts) and he mentioned that the fuel trim pcm self learning will also assist my changes but he recommended a good engine tuning which I planed on getting next month anyways.

**mrr23** · 04-28-2008, 05:58 PM

Originally Posted by 01blackbird

Let me ask you this, do you have the low or high pressure pump that is offered by Walbro? And what is the hot wire kit all about? Is that to keep higher voltage to the pump instead of the varied voltage? Thanks.

i have the high pressure. the hot wire kit just keeps a constant 13 volts by running a larger wire from the alternator to the plug in at the tank. here's a pic of the harness

http://www.racetronix.com/product/RX...99-FPWHG-2.jpg

**mrr23** · 04-28-2008, 06:02 PM

Originally Posted by 01blackbird

Do any of you guys have any issues with too much fuel pressure running these hot wire kits? It seems like at idle or at lower speeds where fuel pressure demand is low that it would be too much.

fuel pressure at idle is 58psi. at WOT it drops slightly. with the hot wire kit, the fuel pressure went to 62psi and stayed around 58psi all through the rpms.

**01blackbird** · 04-28-2008, 06:27 PM

Originally Posted by mrr23

fuel pressure at idle is 58psi. at WOT it drops slightly. with the hot wire kit, the fuel pressure went to 62psi and stayed around 58psi all through the rpms.

Sounds good to me. I just ordered the pump and hot wire kit. Hopefully I'll have it by this weekend to install. Thanks again.

**Frost** · 04-30-2008, 04:37 AM

Actually, our cars ARE return style fuel systems, just different than what pops into your head when you think of a return system. If you follow the pump's output line from the bucket for a few feet under the car, it goes into a TEE fitting. Of the TEE's two "outputs", one goes up front to feed the rails and the other returns (yep, there's the word) to the bucket where it goes through the regulator and back into the tank. The issue with this of course, is that a regulator in the tank on a short return has a problem keeping the fuel pressure really regulated up front during high demand or transistional demand.

**mghawk57** · 04-30-2008, 04:58 AM

So Frost are you saying after a given horsepower that a dual in tank system won't work and than you have to set up a new fuel line and true return.

**Eagle** · 04-30-2008, 06:27 AM

IMO, to really see the benefit of a dual pump setup you need to increase the size of the line running to the fuel rails anyways. At that point the existing feed makes a great return! Tons of great info on this at ls1tech too...

-Eagle

**knappbunch** · 04-30-2008, 07:20 AM

Originally Posted by Frost

Actually, our cars ARE return style fuel systems, just different than what pops into your head when you think of a return system. If you follow the pump's output line from the bucket for a few feet under the car, it goes into a TEE fitting. Of the TEE's two "outputs", one goes up front to feed the rails and the other returns (yep, there's the word) to the bucket where it goes through the regulator and back into the tank. The issue with this of course, is that a regulator in the tank on a short return has a problem keeping the fuel pressure really regulated up front during high demand or transistional demand.

were you in virginia beach this week end for the car show?

**knappbunch** · 04-30-2008, 07:23 AM

Originally Posted by Frost

Actually, our cars ARE return style fuel systems, just different than what pops into your head when you think of a return system. If you follow the pump's output line from the bucket for a few feet under the car, it goes into a TEE fitting. Of the TEE's two "outputs", one goes up front to feed the rails and the other returns (yep, there's the word) to the bucket where it goes through the regulator and back into the tank. The issue with this of course, is that a regulator in the tank on a short return has a problem keeping the fuel pressure really regulated up front during high demand or transistional demand.

i eas told by sean at va speed to buy a set of rails and bigger injectors use the stock line a return and run dash 8 to tank with high flow pump. I have an 02 ss with sts. they say with the new 255 pump they just put in my injectors are still at 107% duty cycle. what should I do.