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How many HP is a 454 mag?

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Old 02-25-2009 | 09:55 PM
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Default How many HP is a 454 mag?

How many hp is a 454mag? I've been told is was 365 and also been told it's 385hp. Can anyone tell me which one it is. Also what would it take to bring it to 500hp?
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Old 02-25-2009 | 10:07 PM
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Originally Posted by WaterJunkie
How many hp is a 454mag? I've been told is was 365 and also been told it's 385hp. Can anyone tell me which one it is. Also what would it take to bring it to 500hp?
454 mag = 365 and 454 efi = 385 .
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Old 02-25-2009 | 10:09 PM
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Thanks... any idea what it would take to get it around 500hp?
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Old 02-25-2009 | 10:54 PM
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Originally Posted by WaterJunkie
Thanks... any idea what it would take to get it around 500hp?
Good heads, cam and intake. 500hp isn't that hard with a GOOD set of heads. That's really where the hp is. (AFR) comes to mind.



Darrell..
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Old 02-26-2009 | 01:40 AM
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To make 500 hp is going to cost about 6k on the conservative side. 2k for heads, 2k for exhaust and 2k for everything else.
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Old 02-26-2009 | 06:22 AM
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buy a used HP500 (9-10000$), sell your 454 (5-6000$) in your resale will be better in the end.

But that's just an opinion...
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Old 02-26-2009 | 09:09 AM
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What year is your 454 Mag? They were rated at 350hp at the prop in the 1991 Merc brochure I have in my hand.
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Old 02-26-2009 | 09:24 AM
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I believe the fountain it came out of was an '89.
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Old 02-26-2009 | 09:26 AM
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It is a 365 HP on the flyweehl and 350 at the prop !!!!


If u whant a little more HP i would not mess with the internals at all ,,,just stick a small procharger on it and u have 500 + HP easy and still reliable.
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Old 02-26-2009 | 09:39 AM
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The 454 mag had as little as 330 HP. not 100% sure about 1989
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