Estimated horsepower on rebuilt 454 mag??
#1
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A friend just rebuilt a 1997 Merc. 454 Mag and kept it completely stock except for the below changes. Can anyone estimate what the horsepower is?
1. Rebuilt at .030 over
2. Compression ratio 10:1
3. BG SeaDemon 750 CFM Carb
All else is stock.
Thanks.
1. Rebuilt at .030 over
2. Compression ratio 10:1
3. BG SeaDemon 750 CFM Carb
All else is stock.
Thanks.
#5
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Join Date: Jul 2007
Location: king george, va
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Don't you first need to know what the factory hp rating was on the motor or was there only 1 option that year, I know my boats older and there were 3 different hp ratings depending on the heads
#6
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There was only one "454 Mag" motor (with a carb) in 1997. The other motors were referred to the "7.4" and the "454 Mag MPI "(or possibly EFI instead of MPI). I believe the "454 Mag" was rated 350HP at the prop that year and the MPI variant at 385HP.
#8
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Should have changed the cam as well. That could bring another 30-50 hp.
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