454 Magnum Upgrades

[Tommy Gun]

I have an stock Merc 454 magnum EFI 385 HP in my 1995 Cig 20.

It is time to upgrade the motor/headers. Whats out there? Any recommendations? Whipple it?

 

[Wrinkleface]

Sterling 1500!!!

 

[Tommy Gun]

I want to upgrade the motor not replace it...

 

[Bill N]

Jc Performance got 515hp out of mine with the stock heads & intake. He just used a 525 cam, ported the heads & a good program of the efi.

 

[Trim'd Up]

I want to upgrade the motor not replace it...

That's a shame. I have a 711 hp 548 that sure would make it fly.:driving:

How much power are you looking to get?

 

[bajabob 718]

do the heads and cam bigger prop :driving:

 

[Tommy Gun]

That's a shame. I have a 711 hp 548 that sure would make it fly.:driving:

How much power are you looking to get?

Much as I reasonably can out of this rebuild.

Has Bravo 3.

 

[mikes280]

bore it 60 put a 4.25 crank in it touch up the heads add a crane 741 and you have a 496 that can make up to 600hp

 

[JupiterSunsation]

How fast is that boat with the stock motor now?

 

[Tommy Gun]

How fast is that boat with the stock motor now?

68

 

[Knot 4 Me]

Are you sticking with the Bravo III after the rebuild or going to a Bravo I? That decision should influence how far you want to go HP-wise with this upgrade.

 

[Airpacker]

Put a Black Hawk on it and gain mph for cheap

 

[Tommy Gun]

Are you sticking with the Bravo III after the rebuild or going to a Bravo I? That decision should influence how far you want to go HP-wise with this upgrade.

Going to try it with a Bravo 1 lower...we'll see.

 

[Tommy Gun]

Put a Black Hawk on it and gain mph for cheap

Blackhawks have their own set of issues (shifting), but I have considered an Arneson as it would appear that it would produce he desired result and decent dockside manners.

 

[Airpacker]

Blackhawks have their own set of issues (shifting), but I have considered an Arneson as it would appear that it would produce he desired result and decent dockside manners.

What shifting issues? never had a single shifting issue in 5 summers of running one behind an efi motor.

 

[baja27]

Tommy Gun , I have a M1 procharger for your motor, keep everything alone and enjoy great cruise speeds without going into boost.

 

[Bad Idea Baja]

Tommy, I'm really happy with what I did to my 454's. If you want the cam specs & stuff like that, PM me.

 

[Tommy Gun]

What shifting issues? never had a single shifting issue in 5 summers of running one behind an efi motor.

I have been told they have problems with higher HP and have to be shifted like a crash box????.

 

[Knot 4 Me]

I think the first question a builder would ask is if you want to keep the EFI system.

 

[Slandrew]

:iagree:

Jc Performance got 515hp out of mine with the stock heads & intake. He just used a 525 cam, ported the heads & a good program of the efi.