blow off valve on supercharged motor
#21
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This is a old thread but I never did get a blow off valve or unloader valve, I was worried at the time (and it still makes me nervous) when I pull throttles back too fast that I get a big blower surge and that it might destroy the impeller (I think it was right after this thread 5 years ago that I DID have a supercharger fail but it was from bearing failure accelerated by turning blower higher than it's rating), Smitty
#22
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I lost an impeller too and they fixed it for free the new unit has less than 1 hour on it and the whole system is for sale cheep 419 473 2628 bonnet blow thru dean nickerson carb pop off valve the works ................get it off my shelf.
#23
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Thread Starter
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I spoke with ProCharger when I was building by 515 ci BB in my 272 Baja with a M3. I was running the 7 psi pully and they said I was on the verge of needing a blow off valve but could most likely get away with it. Cars need them because of the higher boost presures. The engine ran 968 hp on the dyno and has also run 90 mph on GPS. I also did not use the carb enclosure, but the ProCharger Comp blow throught bonnet. I had a custom blow through carb built from the Carb Shop for the engine.
#24
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I missed this post first time around, did you make 968 hp at 7 psi of boost or did they just call the pulley a "7 psi " pulley? Your speed is right inline with what mine was with almost exact power level I had at the time, I'm glad to see your post and numbers so I have sometghing to compare my boat to. I made 945 hp back in 04 or 05 but I was running more like 13 psi of boost but at the time my boat would run 89.5 or so with a full tank of gas and 4 250lb guys in it and saw around 92 running light. I have since upped the power and see around 95-96 mph w/my 1050 hp pulley or real close to a hundred with my 1115 hp pulley. I have been told boat should be much faster with that much hp but for Christ sake its so far past the hull limitations who really knows how fast it should go with that kind of power, Smitty
I am surprise that yours does not break 100. You are making some HUGE power.