Hi everyone. I am in an information gathering phase for a project I want to start. Gonna be building (hopefully) a 427 stroker LSx with a Procharger and looking to make 1000 flywheel horsepower on 93 octane. It will be intercooled but no methanol injection. I was hoping to get away from a multiple pump setup if possible, and came across this Walbro pump they call the Hellcat pump. It is rated for 525 LPH but it specifies E85. From what I have read, ethanol requires more flow (30%-40%) to make the same power as gasoline, so does that translate into this pump having a lower LPH rating for gasoline? This pump seems ideal, as I have seen posts that people are taking twin 255LPH pump setups into the 1200 wheel horsepower range...way more than what I am looking to do. I would appreciate any insight on this. From what I understand, flow is flow as long as the viscosities of the liquids being tested are similar. I would like some clarification on something though. If you look at the specifications for the Hellcat 525LPH pump, it specifies that the pump is good for 700HP forced induction and 900HP naturally aspirated. So in my case, as I want to run a Procharger...
525LPH=700HP crank FI
Now twin 255LPH Walbro pumps are knows to support up to 1200 wheel HP, which depending on parasitic losses is probably closer to 1500 crank HP (I assume). But 2 255LPH pumps should equal out to 510LPH, which means...
510LPH= 1200-1500HP crank FI
My question is regarding the math here as something doesn't add up to me...
If twin 255's can support 1000+ HP forced induction, then why can't I use 1 in tank Hellcat 525LPH?
Hope someone a little more knowledgeable can clears things up for me...

 

Twin 255’s can get into the 1000-1050 range. They wont do 1200 unless you keep fuel pressure way low and dont have to run alot of boost to get there. I had to run 3 to get there on my setup since i was in the 30 psi boost range, and thats with a turbo

a blower will take 100-200 hp to drive depending on the power and boost etc

a 525 lph should get you to 1000 flywheel on gas. It is the largest pump you can get. It flows the same for e85 as it does for 93
run a -8 an sized feed line

 

Orr: I figured as much, but I was also under the impression that increasing the fuel system pressure (as is required by nature of a boosted engine at a 1:1 rising rate) reduces the overall volume. My plan was to "go big" so to speak, meaning that using a larger displacement engine, the highest flowing cylinder heads (AFR 245's most likely) and a better flowing head unit such as the F1-A/C/R would result in attaining the 1000 crank HP mark at a lower boost level. By reducing the amount of boost required, I would also reduce the amount of fuel pressure rise that would be required. At least, that's how I see it in my head. If I had a 350 SBC with AFR 210CC heads and an F1, I might need upwards of 30 PSI of boost to make said 1000HP. Assuming factory fuel pressure of 48 PSI, 30 PSI of boost means that the total fuel pressure at max boost would need to be 78 PSI. Increasing the engine size and efficiency reduces the boost requirement to something like, say, 15 lbs of boost. Then the base fuel pressure of 48 PSI only need to jump up to 62 PSI, which seems more manageable.
I really hope that I can get away with only needing to run 12lbs-15lbs of boost with my proposed engine combination to make the power I want. Hell, if it the engine only comes back with 900-950 at the crank I would be happy. It's going to be a fun street car to tool around in anyway.
I do plan on running a -8AN feed with a regulator on the rail and probably a -6AN return. Speaking of which...
Not to hijack my own thread here but I was toying around with the idea of using the FItech LSx induction kit designed for 750HP. I called them and asked them if the kit could be made to handle the 1000 crank HP I wanted and they told me that they could install 80# injectors to get it there. I feel like 80# injectors are too small and the duty cycle at max boost/power would be greater than the suggested 80% recommended by most manufacturers. Any input on this?
Thanks for the quick reply!

 

You are correct. Pressure goes up volume goes down. Dont want to be much over 65 psi total imo

i ran 40 psi base to 70 psi with boost. Walbro has flow charts. You can get some extra flow with more voltage. Power the pump off the alternator for high voltage

80’s may get 1000 crank. I made 700 whp but running pig rich and saw high duty cycle, so leaned out it may have made much more power and been ok on duty cycle

 

You can also add a boost-a-pump to up the fuel pump voltage under boost. That’s what I did with mine, but it’s not on the road yet so I can’t comment on the effectiveness. Google Ken Belle Boost-A-Pump