Cool Fuel 502 MPI fuel Pump, how much HP does it support? GPH?
#2
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I had wondered what answer to this was before too, most the modded engines I've done have been upgraded.
So recently I dynoed a guys 509, 9-1, promax chinese heads, MPI intake I modded for him, tpis twin 68 mm tb, typical perf cam in the 238/244 @.050 duration. .370 lobe. Stock fuel system except i previously supplied him a re-scaled mefi3 tune and new 60 lb injectors.
So, on my dyno it made 612 hp all out, 600 hp w mufflers on, 580 hp w EMIS w 32" dry to tip tails (all after optimizing the tune). At 600+ hp the fuel pressure dropped from 40 to 35.5 on top, with afrs a little fat, BSFC was .600 plus, used 345 lbs per hour. Leaned out into low 12's the pressure drop was down to 36.8/37 ish, at 13.2 volts, not as bad. So, i did the math backwards, with what i would consider a unacceptable drop, we flowed 210 LPH/345 lbs p hr. The reason i would consider that drop unacceptable is its more that 10% AND IF you tune based around a fuel system thats maxed out IF anything degrades or isnt perfect it might melt down. 39/40 down to 36/37, i can live with, not 35/34 though. Btw, leaned out lbs per hr was in 310/320 range, Smitty
So recently I dynoed a guys 509, 9-1, promax chinese heads, MPI intake I modded for him, tpis twin 68 mm tb, typical perf cam in the 238/244 @.050 duration. .370 lobe. Stock fuel system except i previously supplied him a re-scaled mefi3 tune and new 60 lb injectors.
So, on my dyno it made 612 hp all out, 600 hp w mufflers on, 580 hp w EMIS w 32" dry to tip tails (all after optimizing the tune). At 600+ hp the fuel pressure dropped from 40 to 35.5 on top, with afrs a little fat, BSFC was .600 plus, used 345 lbs per hour. Leaned out into low 12's the pressure drop was down to 36.8/37 ish, at 13.2 volts, not as bad. So, i did the math backwards, with what i would consider a unacceptable drop, we flowed 210 LPH/345 lbs p hr. The reason i would consider that drop unacceptable is its more that 10% AND IF you tune based around a fuel system thats maxed out IF anything degrades or isnt perfect it might melt down. 39/40 down to 36/37, i can live with, not 35/34 though. Btw, leaned out lbs per hr was in 310/320 range, Smitty
Last edited by articfriends; 06-27-2019 at 07:26 AM.
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good info Smitty
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If you want to support some bigger power reliably, ditch the cool fuel and install Aeromotive or Weldon pumps with a by-pass regulator
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Found Aeromotive 11108 , anything cheaper that will get the job done?
Can I upgrade the cool fuel pump with a 525 EFI or something?
Can I upgrade the cool fuel pump with a 525 EFI or something?
Last edited by cyrus77; 06-28-2019 at 12:12 AM.
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To me the 500 and 525 fuel pump look identical. The problem w these fuel systems is there isnt a bigger fuel pump that will go in place of stock one with the way the pump pushes into the cool fuel and if there was, the tiny lines and regulator would be too small. So you end up needing a new pump, new lines, regulator, fittings, hose, fuel cooler and if your doing all that you really should use a inline filter after the pump too. The stock suctiin filter housing can be drilled out and retapped to 3/8, the filter will support at least 850 hp as ive done this on blower motors. But signifigant expense and work to retrofit everything, fwiw, Smitty
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To me the 500 and 525 fuel pump look identical. The problem w these fuel systems is there isnt a bigger fuel pump that will go in place of stock one with the way the pump pushes into the cool fuel and if there was, the tiny lines and regulator would be too small. So you end up needing a new pump, new lines, regulator, fittings, hose, fuel cooler and if your doing all that you really should use a inline filter after the pump too. The stock suctiin filter housing can be drilled out and retapped to 3/8, the filter will support at least 850 hp as ive done this on blower motors. But signifigant expense and work to retrofit everything, fwiw, Smitty
Currently have cool fuel with motor dyno at 530 (dry exhaust and headers) and now has eddie marine thunder exhaust and assume lost at least 30 hp, if not a bit more. Have return to tank and steady 40 psi regulator. Use 3/8 lines to filter, and no antisiphon valve at the tank, then standard Merc fuel lines to rail
Thought about Aeromotine and Weldon but also have read that moving a lot more fuel them needed also heats up the fuel. Don't see needing 500 gph pump, but would like something maybe better then the Airtex pump.
Not trying to side track thread, just offering another thought to maybe get some more thoughts going