Procharging 7.4 mpi's
#1
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Procharging 7.4 mpi's
Have a 312 fastech, looking to install some low boost prochargers and probably 32/34 pitch props. What kind of speed and reliability do you think I can achieve keeping the rpm in the 4600 rpms range? Engines have 425 hrs on them, no problems and don't use any oil. Running Royal Purple.
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If memory serves me correctly, 7.4 mpi's (330 hp?) don't have very robust internals. For the money it would take to add the ProChargers, you might be far happier with a nice pair of 502's or 496's. Just my .02...
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#3
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Exactly what crossed my mind when I read the title to the thread (Procharging 7.4s), before I even opened the thread. I kind of consider prochargers and 7.4s an oxymoron, and there is better ways to spend your money if you want reliability.
#4
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As stated this is a good way to get complete brand new motors.....cause the regular 7.4's will not last long with those!!!! Even good 454 mags to 500hp's I'd strongly recommend a re-fresh at 425hrs before adding Prochargers.
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The 7.4 mpi's are a workhorse of a motor, able to run lots of trouble free hours. But add some boost to those cast cranks, rods, pistons, non-perf valve train, and you will likely find problems even the Royal Purple oil just can't overcome.