99 Whipplecharged Big Block Suburban

[Supercharged111]

Them claiming to increase fuel pressure sounds fishy. Mine never had anything on the return line. Do you have the auxiliary fuel injectors at the throttle body?

 

[Wildblue19]

Them claiming to increase fuel pressure sounds fishy.

I agree, I would think the regulator should keep constant pressure. In my mind the boost a pump could help keep the system from getting starved as the injectors near max duty cycle to keep up with the increased demand.

But, this system doesnt have an aux injector added. For the advertised 350 HP with the whipple (over 290 stock) the factory ~20 lb injectors cannot provide the required fuel, even at 100% duty unless the pressure supplied to them increases.

Maybe the solenoid on the return line is there to pinch off the return flow, increasing the pressure past the regulator?

 

[Wildblue19]

@Erik the Awful has a good post here talking about how the return line restriction would likely enable this system to increase fuel rail pressures on the factory regulator.

 

[Erik the Awful]

The module increases fuel pressure from 55 or so (stock) to 65-75 and 85-90PSI based on engine RPM. There is also a solenoid on the return line.

Maybe the solenoid on the return line is there to pinch off the return flow, increasing the pressure past the regulator?

Bingo. The solenoid blocks off the return, raising fuel pressure.

That's a really dorky way of ramping up the fuel pressure, but I think it was designed to bolt onto an engine without having to upgrade "everything". I'd consider yanking that "fuel booster", replacing the injectors with higher flow units, and reprogramming the chip. But then again, if it's working and you need it, don't dork with it.

 

[Wildblue19]

Having the manual is extremely helpful because it points out all the silly stuff like this. I think we're going to junk the boost a pump and upgrade the in tank pump and do new bigger injectors as well.

 

[Supercharged111]

Having the manual is extremely helpful because it points out all the silly stuff like this. I think we're going to junk the boost a pump and upgrade the in tank pump and do new bigger injectors as well.

Once you change one single aspect of the Whippletronics and base ackwards mechanicals they used, you're 100% committed to a tune. And since the blackbox doesn't support boost, you're also going in on a 411 swap and 2 bar MAP. That's what I did, but I already had EFILive and the knowledge to make it happen. I also added 42# injectors and a 320 AEM fuel pump. If that's something you're interested in pursuing it's definitely the better way to go. But you'd need to have a way to get it tuned.

 

[Vikingdude]

The boost referenced voltage ramp system works pretty well. Whipple used it for years, Vortech used it, kenne bell still uses it, Linfenfelter used the kenne bell modules for a long time, Hamburger just unveiled new kits for the brand new Mustangs that uses it.

 

[Wildblue19]

I also added 42# injectors and a 320 AEM fuel pump.

Which injectors and pump did you go with for this?

We are going to go full aftermarket EFI control on this with a terminator X setup.

I think the boost a pump system can work, but seems like a band aid not addressing the root cause of the fueling issue.

 

[Supercharged111]

Which injectors and pump did you go with for this?

We are going to go full aftermarket EFI control on this with a terminator X setup.

I think the boost a pump system can work, but seems like a band aid not addressing the root cause of the fueling issue.

Boost a pump isn't as ghetto as you perceive it to be. It really does work. But I didn't want to hack up my wiring, so I dropped one of these in the tank.

AEM 50-1000 AEM 340 LPH High Flow In-Tank Fuel Pump

AEM's 340LPH High Flow In-Tank Fuel Pump is designed for high performance naturally aspirated and forced induction EFI vehicles. It delivers reliable performance and a high volume of fuel flow for a very competitive price. The AEM 340LPH High Flow In-Tank Fuel Pump (PN 50-1000) flows 340 lph...

www.aemelectronics.com

Yours being a 99 has the bucket type sender and mine has the older style, so this pump is not going to work for you. For injectors, I grabbed some out of an L67 (supercharged series II 3800) and had them cleaned and flow tested. I'm not sure what your pump options are with the bucket. If you are able to slide one in, the hose from the pump to the top of the bucket will also need replaced. Radium is the only one I know of that makes a compatible hose in the correct size. It's a clear plastic flexible dealie that turns yellow/brown when it gets old.

Submersible Fuel Tubing

 

[Wildblue19]

Gotcha. Thanks for the info. I guess to me, I'd just rather keep it simple & put in a bigger pump rather than try and program in the BAP within the Holley ecosystem.

I did pick up this pump which should drop it and feed all I need. Wiring gauge will probably need to be upgraded for the higher draw of this pump. Will update!