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tomas_wallin 08-24-2004 02:42 PM

How do I get ~450hp out of Merc 454 -95?
 
How do I get ~450hp out of Merc 454 -95 without getting too poor doing it?!

I have been thinking of some kind of supercharger but doesn't really know where to begin... What else do I have to change with the engine to get a supercharger to work?


Thanks,

Tomas

Cord 08-24-2004 03:19 PM

Re: How do I get ~450hp out of Merc 454 -95?
 
Give us what you have to work with. You can do this very easily with a 174 blower or work a small amount and do it N/A.

Gary Anderson 08-24-2004 03:25 PM

Re: How do I get ~450hp out of Merc 454 -95?
 
Is it a 7.4, 300 or 330 hp 454, or a 365 hp motor?

Stormrider 08-24-2004 03:33 PM

Re: How do I get ~450hp out of Merc 454 -95?
 
I'd like to know this too.
I've got a 454 365mag. No blower for me though.

HiPerf2000 08-24-2004 03:53 PM

Re: How do I get ~450hp out of Merc 454 -95?
 
Had a 174 B&M on a stock 330 that dynoed 450hp. Only thing changed were exhaust valves to inconel.

articfriends 08-24-2004 03:58 PM

Re: How do I get ~450hp out of Merc 454 -95?
 
It really depends on your budget and if your starting with a mag motor or standard big block. If your starting with a std motor you might be better to sell it and start with a 502 mag (for the price difference between your old motor's value still running-1000-1500 $ and a long block 502-5200$ (4000$,) you probably would spend that much in exhaust,headwork etc and still have a tired cast piston,cast crank motor that can't take much abuse. Let us know your hours on motor,mag or std and your budget,Smitty

bpine 08-24-2004 06:13 PM

Re: How do I get ~450hp out of Merc 454 -95?
 
I did exactly what you did on my Scarab 21. I started with the 1991 454 Merc Bravo 330hp! The reason why I wanted to stay with the 454 vs. the 502 is I wanted to keep the blower under the engine hatch with no protrusions. The 174 would fit. I was aware that it had cast pistons and crank and not so great exhaust valves! I figured what do I have to lose, if I blow this one I haven't lost anything! I can still use the parts on a properly prepared engine! I installed the 174 on the bone stock motor. Updated to a blower carb that Teague custom marine tuned for a blower, added a Holley red electric fuel pump in addition to stock. Went to a full MSD ignition system! (If I did it again today I would have use the DUI ignition from performance distributors) Changed the prop, set the timing to a modest 28 degrees total advance and 5 psi of boost! RESULTS! Don’t know the horse powers gain, I did get an additional 12 mph on GPS! I was Happy! I ran it without a hitch for three years, and logged 226 hours on it without a problem! I only wanted a year or so! The final demise of the engine was a corroded Merc exhaust that led to a hydraulic lock! Which I didn't care because I had a new motor on the stand! I am sure I am leaving something out, if you have any concerns or questions please ask!


Bryan

articfriends 08-24-2004 09:17 PM

Re: How do I get ~450hp out of Merc 454 -95?
 
bpine,it sounds like that worked out good for you,the 502 is identical to your 454 in external dimensions though so you wouldn't have had to worry about a engine hatch problem compared to your 330 hp motor.

DonMan 08-24-2004 09:51 PM

Re: How do I get ~450hp out of Merc 454 -95?
 
Just glad to hear about those big block dimensions....
I was thinking of replacing the 396 in my Chevelle with a 540. I was very concerned about getting that thing in the engine compartment. :D :stupid:

articfriends 08-24-2004 10:30 PM

Re: How do I get ~450hp out of Merc 454 -95?
 
Donman,i was trying to clarify something to bpine because he said "i stayed with the 454 vs. the 502" because of engine hatch clearence? After re-reading his post i see he meant the 174 blower would clear (which would be too small for bigger motor).sorry to insult your intelligence,Smitty


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