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Is there any fairly easy upgrades I can do to a 454 efi 385hp magnum?

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Old 05-10-2016, 05:59 PM
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Default Is there any fairly easy upgrades I can do to a 454 efi 385hp magnum?

I'm pulling engines out to do plugs, go install new harmonic balancers and just do some general maintenance. While I have them out, I woiuldnt mind doing a few power upgrades. I'm just not sure what I can do, and if the computer is even tuneable.

Any suggestions would be great.

These are non mpi efi mags just to clarify.

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Old 05-10-2016, 06:13 PM
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Computer is tuneable if you have the software.... now as for what you describe as "easy"... Your not going to bolt on an Ebay turbo encabulator and pick up a quick 75 hp. A nice roller cam , exhaust and reprogram can make a difference Arctic friends and panther have both recently posted threads on upgrades...
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Old 05-10-2016, 06:41 PM
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Check the risers and manifolds while your at it. That's the weak link in those motors.
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Old 05-10-2016, 06:44 PM
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No forced induction, I was thinking maybe a cam or headers. I'll see if I can find their posts.

THanks dave, Iw ill take a look when I have them out.
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Old 05-10-2016, 07:20 PM
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Originally Posted by airbats801
I'm pulling engines out to do plugs, go install new harmonic balancers and just do some general maintenance. While I have them out, I woiuldnt mind doing a few power upgrades. I'm just not sure what I can do, and if the computer is even tuneable.

Any suggestions would be great.

These are non mpi efi mags just to clarify.
Roller Cam, Stainless Marine Exhaust, CPU Flash and mill heads a little to get a quick 50hp!
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Old 05-11-2016, 05:56 PM
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THanks for the reply. I think if I were to bother pulling heads, I'd just go with a set of aluminum heads. I dont run saltwater so it shouldnt be an issue. Maybe I will save that until next season.
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Old 05-11-2016, 06:28 PM
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Easy gains, no, moderate priced gains, yes. Cam upgrade, cam upgrade, cam upgrade. The cam is lame in 454/502's. I have a 2000 502 mpi on my dyno right now, flat top pistons (less compression than stock) bored throttle body, fully ported intake, stock heads with 4-5 hours of minor grinding on ports (I did myself).550 hp and 585 ft lbs of tq heat soaked with just a 500 efi cam on 89 octane and lots of tuning. No reason a 454 couldnt gain 50-80 hp even without the porting with a good cam upgrade. All the other stuff you see (air cleaners etc) are FLUFF, The hardin aluminum adapter/kn element setup KILLS hp so dont waste your time
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Old 05-11-2016, 07:38 PM
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The best bang for the buck would be an intake and carburetor.
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Old 05-12-2016, 10:19 PM
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Originally Posted by articfriends
Easy gains, no, moderate priced gains, yes. Cam upgrade, cam upgrade, cam upgrade. The cam is lame in 454/502's. I have a 2000 502 mpi on my dyno right now, flat top pistons (less compression than stock) bored throttle body, fully ported intake, stock heads with 4-5 hours of minor grinding on ports (I did myself).550 hp and 585 ft lbs of tq heat soaked with just a 500 efi cam on 89 octane and lots of tuning. No reason a 454 couldnt gain 50-80 hp even without the porting with a good cam upgrade. All the other stuff you see (air cleaners etc) are FLUFF, The hardin aluminum adapter/kn element setup KILLS hp so dont waste your time
Thanks for the reply, I completely agree with you on air filter, waste of time.
Do you have any specific cam recommendations? I really dont need much more speed out of the boat,m but since they are out, I figure why the hell not.


As for the othe reply, man I'd really hat eto go back to carburetion, the fuel injection is so damn nice, but it sounds like this intake is a bit restrictive? I know it flows quite a bit more than the mpi manifold though...
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