Procharging 500EFI's
#11
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the fuel and spark compensation tables(boost) are very large and can really fine tune the running of the engine.
the hp500's that I tuned went thru 3 stages,stock tune fixed(mefi4b conversion) then 540's afr heads and cam change,,then last summer a bigger cam than the 1075 cams we were running.
all tuning done in the boat w/ o2's,,took 4hrs from the dock to 110mph blasts.went 115 but only held the o2 meter to say go,no go.![Big Grin](/forums/images/smilies/biggrin.gif)
boat rips now,friend is very very happy.
the hp500's that I tuned went thru 3 stages,stock tune fixed(mefi4b conversion) then 540's afr heads and cam change,,then last summer a bigger cam than the 1075 cams we were running.
all tuning done in the boat w/ o2's,,took 4hrs from the dock to 110mph blasts.went 115 but only held the o2 meter to say go,no go.
![Big Grin](/forums/images/smilies/biggrin.gif)
boat rips now,friend is very very happy.
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articfriends (09-02-2022)
#12
21 and 42 footers
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10 years ago I bought a boat with a pair of Procharged 500 EFI's. No idea on tuning but they ran rich as hell and blackened the transom. I was told when I bought it the engines needed refresh so we soon pulled them, sold the Prochargers, and built 9.8 to 1 compression 540's with heads, cams, intake work.
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articfriends (09-02-2022)
#13
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Just as a side note. Might want to go on Youtube and hear the Prochargers on different applications. I know the newer heli-cut gears are quieter, but they make a lot of noise, IMHO. Particularly in a twin application. I sold mine and went turbos.
#14
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Video link... (may have to quote me to see it unless IB has fixed the issue)
WOO HOO ! the embedded video WORKS !!!
#15
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That's not bad! I had old school M1's and they were noisy! LOL!
#16
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Prochargers can make a ton of hp, fairly low parasitic drag. For years guys jacked up fuel pressure under boost vs actually tuning them. Now with all the high impedance, hi flow injectors you simply swap in larger injectors , set base fuel pressure then open up pw under boost (as far as tuning).
in old days guys ran them with stock tune, no stat, the ect table adding fuel until 140 but motor ran 100 so transom was black, oil was gassed ip, plugs fouled.
mefi4 would be nice but if you only plan on running 7.5 lbs boost or less and not trying to turn motor over 6000 a mefi3 has boost multiplier tables to 150 kpa. I've tuned mefi 3 blown boats that ran fine
in old days guys ran them with stock tune, no stat, the ect table adding fuel until 140 but motor ran 100 so transom was black, oil was gassed ip, plugs fouled.
mefi4 would be nice but if you only plan on running 7.5 lbs boost or less and not trying to turn motor over 6000 a mefi3 has boost multiplier tables to 150 kpa. I've tuned mefi 3 blown boats that ran fine