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Fuel system upgrades on MPI SC Apex for sea level


So far two guys have stepped with $200 up to obtain Art's info, one 10,000 ft up and one flatlander. I'm sending that money to Art. Waiting for Art to give me fuel pump upgrade info (necessary to match his Boondocker numbers) since as you can see on my website his fuel pressure is higher than stock.
 
Jim, did you try to lean it out or is that because you just ran out of race fuel? .61 bsfc. Thats two-stroke territory. Hate to gas that up every 50 miles. Would have been nice to see power at max cackle. Any reason he didn't add a couple head gaskets for pump gas, or turn down boost to 10 lbs? Mike
 
SCfuel mgt

Mike yes we used all of Art's race gas doing the mapping (plus we nearly set fire to his track with red hot exhaust) but when we safened it up we only lost about 1% hp going from .5 to .6. (I aborted the .50 run at 9300) but when we clicked in another 20 lb/hr of fuel we only lost one HP at 9300. Plus the blower takes some hp to drive (maybe 15hp?) so we have to add that to the observed hp (@238 plus 15 = 253 divide into 143.8 lb.hr = .57). As I recall the Eaton roots type blower capable of 250hp requires over 20 hp to drive, the centrifugals are probably easier to drive at high rpm.
That final dyno test on Art's sled was 12 seconds wot on mostly 93 octane, with 45 degree air hitting the intercooler directly at 80mph. Art's thinking that the extra 20 lb/hr of fuel to help keep combustion chamber peak temps lower is cheap insurance. But his A/F ratio and BSFC at part throttle in driving conditions is much leaner (12.5-13-1) so his all around fuel mileage should be fine.
 
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