I Got A 2002 Camaro Z28 With Lt Headers, Airbox, And A 150 Shot Of Nitrous. I Went To The Dyno Just To See What Power Range I Was In And We Had To Take Out The 150 Gas Pill And Put A 200 Gas Pill In Because I Was Running To Lean.

The Problem I Have Is Myfuel Pressure Runs At 54 Psi At Idle. But Whwn I Hit The Nitrous The Fuel Pressure Drops To About 25 Psi. Is This Normal Or Is This A Big Proble?

Thanks For Any Help

 

Not normal and a pretty big problem, that is a very large drop. I assume a stock fuel system? Even your FP at idle is a bit low. Maybe start looking into a aftermarket pump, like a Racetronix kit. When was the last time the fuel filter was changed?

Matt

 

Running a 6 speed or the mighty 4L60E AT? I know something about what you are going through. There is a solution. Matt helped me noodle out my issues.

 

Its a six speed. The car only has 38,000 miles on it. But i did change the fuel filter about 8 months ago.

Yes, stock fuel system.

Thanks

 

I knew somebody was going to whip you with a NOODLE, you had it coming!
Hawk

On a serious note i would be looking at a Racetronix Pump.

 

How big of a shot can you run before you max out the racetronix pump system.

 

Hell I knew you'd mess with my noodle. LOL. Still he's right...and you have to appreciate the senseless humor..er ah I mean sense of humor. As John Candy said, I want to party with that guy.

To your thread...From my experiences, i'd say with a six speed and a Racetronix you'll be good. If you are using an AC Delco fuel filter and it's installed properly probably not the issue. Running out of pump may be. Even a Walboro 255, essentially the same pump with a relay and high current supply line (aka Hot Wire kit) would be an improvement. I've heard 650 rwhp on a Racetronix...i believe i maxed mine out on n20 at 585 rwhp with an AT/3600 stall/4.11...the math will give an equiv 6 speed anothe 100 rwhp or so compared to my car.

 

Macon i'm watching you! And that can't be a good thing.

Taking it to P.M.
Hawk

 

Sent you a PM.

 

Voyeur! LOL. To the thread owners...this is a great example of a Cold Fusion man and NX man who get along just fine...see it all good when we are having fun. The advice is real. The jokes are ...well uh a breath of fresh air.

 

Out of the box the Racetronix kit will support right around 600 rwhp. Adding in a fuel rail mounted fuel pressure regulator & return will improve on some of the factory fuel systems limitations therefore pushing support around 650 rwhp. Adding a boost a pump to the Racetronix harness (there is a provision for it) will allow for a bit more HP support.

Matt

 

Matt please explain how the Fuel Rail pressure regulator works. The Boost a Pump uses a transformer to up DC voltage to what (variable from 13- ? Volts DC)? What's you opinion on how that effects the life of the pump too. Thanks.

 

Does he need to post twice????

Now off to the BASEMENT for me.
Hawk

 

Your basically relocating the fuel pressure regulator from the rear of the vehicle up to the front, as close to the fuel rails as you can be. Now your fuel pressure will be more stable where it needs to be, at the injectors/solenoid(s) & nozzle(s). In some big HP situations with the stock regulator you end up with some FP fluctuation, causing an overly rich condition while spraying and giving up some power. Relocating the regulator up front solves that.

The BAP can up voltage to around 17 volts I believe. They also work as a voltage regulator too so it compensates for voltage fluctuations in the electrical system. As for negative effects on a fuel pump being used with a BAP I don't think you will see any, only positive results.

Matt

 

So the regulator in the rear is outside the tank? I was considering the effects of running higher voltage to a DC motor than it was intended to run on. Now that assumes it's inteded to run at 12-13 vdc. I'm guessing an extra 4 volts won't create much of an issue?

 

I suggest trying to figure out the cause of your problems before just changing out the pump. Like Matt said, your idle pressure seems a bit low and that huge amount of pressure drop when the system activates is definately not supposed to happen. How did the car react when you went to a bigger fuel jet? Generally, if you have over reached the max capabilities of the fuel system, a jet change won't make a difference because the pump simply can't provide enough fuel regardless of the fuel jet size.

 

When i changed the fuel jet it made the car run rich when the system was activated. Like i said before it was running lean before the switch.

Thanks

 

I'm glad you posted that...when I maxed out my pump we went from a 32 > 35 > 38 or something close...Air Fuel changed a bit, but very little as I recall, but the pump was simply unable to keep up. I kind of got caught up in the fuel system part...definately troubleshoot your issue...thanks Jeremy.

 

Based on the this statement I don't think you are maxing out your pump. I recommend doing some checking on the fuel system to see what could be causing the issues.

What nitrous system are you using? What jets? Where are you measuring the fuel pressure at, and are you sure the gauge is accurate? What exactly were the air/fuel numbers before and after the jet change?

Sorry for all of the questions, I'm just wanting some more information to try help figure it out.

Macon- No problem, just here to help. It seems like the majority of the time when people post questions about fuel issues everyone just recommends changing to a bigger pump instead of trying to figure out what is actually causing the issues. I have seen an F-body put down over 600rwhp with the stock pump and with out a hot wire kit or boost-a-pump. While I highly do not recommend trying to do the same, I also don't believe that people should run out and upgrade the pump just because they are having issues with either the fuel system or with not putting down the numbers that a car should. Ok, I'm off the soap box now

 

I am using the NX dual Fogger kit. I am mesureing the fuel pressure at the end of the fuel rail. I do not know if it is accurate. When i had the 150 gas jets in there, when it hit the nitrous it spiiked to 17:1 and slowly went down to about 12:1, but it gradually fell. When i put the 200 gas jets in there and hit the nitrous it spiked to about 16:1 and dramatically fell to about 11:1 and from there fell to 10:1.

No problem on the questions, i know you need more info to help me figure this out.

Thanks