A slightly different 7.4 question...
#11
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Originally Posted by bobl
Concerning the rectangle to oval port mismatch. On an EFI engine it doesn't create a big problem since it is just air moving through the intake. The fuel is injected directly into the port.
Hey bobl,
Would you say that the AZ Speed/Volvo Penta MPI system I have from a 454mag would work well on my modified 1999 7.4MPI even with the intake port mismatch?
The GM MPI did not work well with the cam change I made. Didn't gain much at all and it would not idle correctly. After 3 attempts to calibrate the ECU, I just went back to the stock cam and cal.
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Patrick
Patrick
#12
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Sounds like I'd be better off just bolting on some new exhaust and maybe having the heads cleaned up with new springs. Motors have about 450 hrs on them and run well as is - probably shouldn't borrow trouble!
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#13
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Pat, I think it would work just fine. The hard part would be ECU mapping. Without an 02 sensor or dyno you're just guessing at fuel mixture. I doubt anybody has a "canned" program for your combination. If you were going to mess with that, invest in an A/F meter with wide band 02 sensor. They are a lot cheaper than an engine.
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I'd run em til they are done ...Then .... Victory marine has 496's complete for about 10K HO's 425hp ....just drop em in .... or sell your 454's now ...wonder what you could get for em ?