According to the General Motors instructions with the LS427 crate motor, my engine needs a fuel pump that can supply 53 gallons/hour at rated fuel pressure. Most 255lph pumps can provide this at 60psi. I was thinking that a 340lph pump would leave some margin for error.

I want a reIiable pump that I don't have to worry about. The pump must work in a 4th gen bucket without modifications. In other words, it has to have the venturi to keep the bucket filled even at low fuel levels. Drilling/cutting holes in the bottom/side of the bucket results in fuel problems at low fuel tank levels; usually below 1/4 tank.

Racetronix reputation has taken a hit lately. I did some research on Quantum pump and there isn't much information. Aeromotive has a different type of bucket assembly and I'm not sure how it fills up. I think they probably make good pumps. I'm running a Deatschwerks pump in my LS376/480 swapped Mustang coupe and I trust their pumps. I called them and they told me that they don't make a venturi pump that would work with the 4th gen fuel bucket.

I trust Walbro pumps. I found this on WS6store's website: 99-02 LS1 F-Body Complete Fuel Pump Assembly W/Walbro 495LPH Hellcat Pump Installed (up to 1000HP)

Way too much pump for my engine but I love that it has a Walbro pump. Other than using more electrical power and maybe some added recirculation heat, what would be the downside to using this pump assembly in my paltry 570hp engine?

 

we all do mate, we all do...

 

I have had a Quantum 255 LPH in my daily for 7 years without any issue

 

I used an aeromotive stealth. If you don't want to worry about your fuel pump trap door it.

 

Thank you for posting your experience.

 

I guess when I do research on things like this, I read all the bad stuff because they're upset and rightly so. There are probably a lot more successful experiences that we don't hear about.

This has led me to believe that most of these pumps are unreliable and that's probably not the case. Still, there is concern.

 

Awesome. This is the Aeromotive I was thinking of using: Direct Drop-In In-Tank Fuel Pump Kit, 99-02 Camaro

 

i have the 340L and it has been great w my little supercharger setup. No fuel issues @550 hp. I think the 340 is good up to 700 hp(ish)

 

I don't suppose you're running the 4th gen pump assembly that I linked above, right? I know the pump itself will be the same. I called Aeromotive a week or so ago and I asked them how their bucket fills with fuel. I didn't fully understand what he was telling me and it made me uncomfortable when he said that the bucket has vents or holes or trap doors at the bottom/sides.

I'm glad that yours has been working good for you. It's always nice to hear something positive!

 

What are you going to be doing for the fuel pressure regulator and fuel supply & return lines?

3/8 supply and 5/16 return should be OK for a 340 LPH fuel pump but IDK about a 495 LPH fuel pump.

In the Turbo Buick it has 3/8 supply and 1/4 return with the EVAP being 5/16 for some reason. That's fine for a 255 LPH fuel pump but not for a 340 LPH or bigger fuel pumps. With the bigger fuel pumps that is a lot of fuel to return through a 1/4 line at idle.

 

If going through the process of upgrading the Fuel Lines...

I would consider -8AN (1/2") feed and -6AN (3/8") to be the absolute minimum selection.

Pump selection will most often dictate minimum Line sizes.

 

I was looking at this regulator but I'm open to suggestions: Compact EFI Fuel Pressure Regulator

I've got the stock lines out of my 1987 IROC, I don't even know what size the stock feed and return are. My thoughts were to bend my own feed and return using 3/8" nicopp tubing. I did this with my LS376/480 swapped, 1991 Fox coupe. Tons of work but it turned out really nice

 

That seems pretty big for a fuel injected, 570 crank hp engine. Maybe the 495lph pump that I linked in the first post requires it. I'm all for learning more because I'm definitely not an expert on this stuff.

 

Im using the 3rd gen drop in unit. I used a 6an feed and return w an aeromotive adjustable regulator and filter. Honestly, I would run the same diameter feed and return. My old system w a 3/8 feed and the 5/16 return ran warm after driving a while. Between the returned fuel
from the engine and pump resistance the fuel in the tank got warmer and it killed the pumps. Now on a hot day and driving for an hour or two, fuel gets to 100-105deg. Also, don't over pump it, you'll just build heat w a really large/expensive pump. Using 6an will be fine if your 570hp. But if you wanna future proof it use 8an. Who knows, maybe you'll need a supercharger in the future.

 

I'm running the Aeromtive system with the 340lph pump through -6an line without any issues. Car makes 515whp at the wheels. No fueling issues up to 7200rpm. It should be perfect for your combo. I would have run -8an but the sending unit only comes in -6 and Aeromotive says its good up to 700hp or so N/A.

 

Firechicken, thank you for letting me know that you're using a 3rd gen drop in fuel pump unit. I'm definitely going to use a 3/8" fuel return. More than likely. I'll use 3/8" for the feed as well. 3/8" nicopp tubing is fairly easy to work with and I know that it's capable of flowing a lot of fuel under fuel injection pressures.

The 495lph Hellcat pump, 4th gen module that I linked in the first post is overkill for my current combination. I had mentioned to my wife yesterday that one of my fears with it would be excessive heating of the fuel.

ShiftyCapone, thank you for letting us know that you've had good results with your Aeromotive pump. I know that 340lph pump would be plenty for my 570 crank hp engine.

 

Different Model Fuel Pumps will state if Fuel Line sizes need to be the same size or if the Return Line needs to be a different size.
Different Model Fuel Pressure Regulators will often state similar requirements.

From experience will Fuel Systems ranging from Stock to Exotic Fuels in Engines making 5,000 - 10,000 HP...
Going to a larger Fuel Line size will usually result in cooler Fuel/ cooler Fuel System Components, and longer life of the system.

Greater Fuel Flow circling the Fuel System around and around is a very good thing!

 

obviously you are correct. The areomotive 340L units are set ip w 6an fittings. I considered using 8an lines and was gonna use 8an to 6an reducers at the sender, one at the feed and one at the return. Does anyone think that would have been beneficial other than the increase in fuel in the lines? The flow is only as fast as the tightest restriction allows at a given pressure.

thoughts?

 

I think that this is mostly true. Once the fuel gets past the -6 restriction, I would think the bigger, -8 lines would present less of a flow restriction due to sidewall friction. Sounds like it would be time to crack open a college, fluid dynamics book to really know for sure.


Earlier today I called and spoke with a tech at Aeromotive. We discussed the 340lph pump assembly in more detail. At the end of the conversation, I asked about fuel line size for a very large pump, i.e. the 495lph Hellcat pump that I previously linked. He said that a big pump like that will require -8 feed and return lines. He said you plumb for the pump not for the engine. His car has a 450lph pump and he's running -8 size lines. He said that using small ID lines on a high output pump like that really puts a strain on the pump and will shorten its life which is what vorteciroc is saying in the first quote above.

Here is a link to the instructions for the Direct Drop-In In-Tank Fuel Pump Kit, 99-02 Camaro

If you scroll to page 11 and look at Aeromotive's plumbing schematics, they show -6 feed and return lines for their big, 450lph pump. That just doesn't seem right and isn't consistent with what I was told on the phone today. I'd never run a small -6 feed and return on a pump of that size.

 

I'm using an Aeromotive Stealth 340 mounted in a stock sending unit with stock sized stainless lines from inline tube. At the engine I have Saginaw to -6an adaptors and braided stainless lines to an Aeromotive fuel pressure regulator feeding a Holley Super Sniper 4150. This is on a 427ci Gen1 small block that dyno'd at 575/550 with a 650 carb and $50 amazon HEI. Another bonus is its loud enough to know its working but not so loud you can hear it over the radio. I am also using stock wiring from the C100 back and a 15A fuse.