EFI fuel pump, problems being too big?
- Thread starter RabbitHoleSS
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Just curious how would that work with Holley's EFI in tank 255lph OEM sender replacement pump? The info says it already has a built-in return in the pump assembly that maintains the fuel pressure. Not sure how having an FPR when the Holley EFI has a built-in return would be of any use?
I have ditched the C5 combo feed/return fuel filter in the past, replacing with an Aeromotive AFPR on my twin turbo 01 Z06, and with the stealth ram on my SBC '91 Camaro. Using the AFPR on my 01 twin turbo Z06 that I built (Vette Magazine Dec 05...Horsepower Party) ended up making 850rwhp w/18# boost on a forged 347cid using the stock rail, return tapped into the center rail to the AFPR to the tank, 255lph Walbro, 60lb Motron Injectors, and a KB BAP. Non boost referenced, the fuel pressure would go from 58psi to 72psi (BAP) and hold to redline. The CTS-V I purchased another guy built and he really didn't know what he was doing, he had tapped into both fuel tanks with bulkhead returns and crossover and then used two auxiliary pumps to boost the fuel pressure the car made a 1000hp with 2 100 NOS shots on top, but so did my 347 twin turbo without NOS.
My goal is to just have a stock LS1 in my G Body, wasn't sure if the Holley EFI in tank OEM drop in would work with the OEM 04 Vette ECM that is coming as part of the complete drop out.
Here is the pic of the twin turbo and fuel return system I designed back in 2004. A friend of mine who builds Supercharger kits after seeing my design, came up with his own where he put the return on the end of rail at the Schrader valve, and then to the Aeromotive AFPR to return to the tank.
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As far as the tune goes, you still have to delete vats, rear o2, egr, and get your fans working atleast. The corvettes pcm will run the holley drop in, no problem.
This is what you want to use, correct?
www.holley.com
Streetbu has this unit in his Malibu and has posted nothing but positives about it, If you haven't talked to him, I would. He's always answered my questions.
This is what you want to use, correct?
Holley Sniper EFI 12-306 Holley EFI Fuel Tank Modules - 255 LPH - GM G-Body Vehicles
This in-tank fuel pump module is a high-pressure unit that flows 255 liters per hour (LPH) and is capable of supporting electronic fuel injection (EFI) engines producing up to 550 horsepower. Featuring a pre-calibrated fuel-level sending unit designed to work with the factory fuel gauge for this...
www.holley.com
Streetbu has this unit in his Malibu and has posted nothing but positives about it, If you haven't talked to him, I would. He's always answered my questions.
I don’t think that motor and turbo combo made 850whp with the fuel setup you’re describing and is the pics.
The easiest setup going is a Walbro 450 attached to the stock pickup (with minor modifications) and either a budget or high quality FPR. It will handle 500whp safely, repeat safely, all day long.
I believe Racetronix makes a nice dual pump drop in setup, but it’s pricey.
And I don’t want to argue / start poop, but there is no way you made 800 on a 255 Walbro. And for that matter that is a tall order on 2 255’s. And if they weren’t boost (manifold) referenced like you picture shows, then it would 2/3 of that.
Oh but it did and is well documented. Like I said I did it myself and the article is in Vette Magazine shows when it was at 745 rwhp on 14psi. Then I ran it on the dyno for the A&A Corvette party and it made 815rwhp. I was also one of the first to use HP Tuners 3 bar Speed Density software, with the car appearing on HP Tuners website. If you re-read my mods it was an LPE 255 walbro pump with Ken Bell Boast a Pump (one wire) and the other mods I mentioned. 72psi at 6700 rpms, non boost referenced at 18# psi boost, tuned on Sunoco 100 octane pump gas. With the boost controller off on the stock waste gate springs 8.75lbs, and 91 octane it was making 590-610 whp depending on whose dyno and day etc. Below is the dyno graph from the Vette Magazine article in Dec 2005, the initial tune with HP Tuners Speed Denisty 3 Bar software is in black. Made 834 whp, all with the fuel system exactly as I have pic'd and described above..
I have been away from LS1s for 10 years now, as I've been busy with my C7Z and Maggie 2650 mods and have probably forgotten more about the LS1/LS6 then most people, but with all of the updates from when I was helping pioneer the first ATI Procharger D1 (in the U.S.) back in 2002, and twin turbo systems, it is nice to see all the support now for resto mods and LS1 swaps and experience and products available. So I look to those that know about it like people did with me earlier with the C5 Corvette and forced induction mods.
I also attached the video making over 800whp. Funny thing is I didn't know the individual filming, he sent me the video on the Corvette Forum. Andy's dynojet I think was a 248x rated at 1100hp, at over 800whp I was pushing the limits and you can hear how high the dyno winds up at the end of the video. Nobody else's car that day made the dyno sound that way lol. Final tune was 850whp about 6 mos later after I removed the Borla cat back mufflers and replaced with Corsa straight pipes. But all that was also through 2.5" exhaust. The reason it is quiet at idle the PT52 T4 turbos muffle the sound until it is full spool.
Looks like I can't attach the video, trying to link. Dyno run starts at 3:15....you can hear somebody say, "it made less this time", that is because it was the 2nd pull and everything was heat soaked from sitting, first dyno pull was 840 whp. It's hard for me to believe it has been over 15 years since these videos, I appreciate you questioning my fuel system as it inspired me to go back through my files and look for the history. One of the attached pics shows the specs on the build too.
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I followed 81cutlass video to make my own module. Should be good for atleast 1k Llamathrusts.
It was pretty easy, the only question I have is should I ziptie the pump at the bottom?
It just sits in there right now.
Also do you guys wash out the new tank with anything or just drop it in?
It was pretty easy, the only question I have is should I ziptie the pump at the bottom?
It just sits in there right now.
Also do you guys wash out the new tank with anything or just drop it in?
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