Marine power 454 or Merc 496?

[rposton1]

I have a chance of getting a marine power 454 or the merc 496 which one is better? thanks....... Robert

[Boozer]

Which one costs less hp per $ ?
Which one has a better warranty?
Which one is going to support the add ons you plan to throw at it?

[rivercrazy]

Questions:
* Is the 454 a 454 Mag? Carb'ed or EFI?
* Do you have plans on upgrading? The 496 EFI is harder to upgrade. It also has cast pistons versus forged slugs for the 454 mag.
I'd say if your going to stay stock, get the 496HO. It would probably give you 2-3 mph more top end. If your going to upgrade, the 454 is a better base to start with and aftermarket parts are cheaper and more available

[BADBLOWN572]

Typically the Marine Power 454 is a carbuerated motor that is put together very well. The Merc 496 is a fuel injected motor that is great in the stock configuration. I think that this will also depend on the setup you are running. I would sugges the Marine Power for a jet setup and a Merc for an IO. Be aware, some of the time the 496 will have problems if additional power is added at a later time.

[surfer2001]

My 454 was a MAG EFI 385 HP, MY new boat has the 496 MAG HO 425 HP. Both ran great, with the extra hp I can run faster at a lower RPM. You don't give enough info to name the better one. Also application needs to be known.
http://www.***boat.com/image_center/data/500/1498myboat-med.JPG

[rivercrazy]

I believe he is getting a 22 foot low profile jet boat

[rposton1]

It will be for a Shockwave 22 sc Jet, I'm going to just do a few mods to the motor so I was leaning towards the 454 mag....Robert:wink:

[rivercrazy]

What are you thinking down the road? Blower or normally aspirated?
You can easily bump that motor from 390HP to 475HP with a cam change, intake, carb, and headers. You will pick up about 4-5mph going that route. Make sure you get a double pumper / mechanical secondary carb for a jetboat. More instant rpm = better accel.
If your thinking about more normally aspirated, heads are the next step. Then your pretty much tapped out unless our go NOS without block related work....
Jets like cubic inches and to go bigger you will need a different crank and pistons along with block work.
With a larger jet, you want good power below 5K rpm or you will have to turn a small impeller at really high rpm and will loose midrange cruising effiency.
I was going through all these scenarios before deciding to go up to the 25 Shockwave Tremor with an I/O

[77charger]

If you plan on adding to it go 454 if you want to leave it stock go 496.
The 454 will be easier to upgrade esp for a person like me.

[Kilrtoy]

isnt Marine poweer 454 a jet and a 496 an outdrive

[JustMVG]

I have the Marine Power 454 Mag in my 21 Ultra with the dom jet , and have had no probs at all and am looking into beefing it up after this season, carb, intake .... the whole thing. You always seem to need a little more ooommph when you have a jet:)

[shockwaveharry]

If you can do it, start out with the 502 instead of the 454. 415hp with all the good internal components. Its a perfect candidate for future upgrades and you may find that it perfect right out of the box. And dont automatically shun the 396. Number one reason: fuel injection. Cams, forged piston kits, aluminum heads, exhaust and bigger oil pans are allready available for it and Marine powers version comes with a controler that can be programmed for any modifications you make (easier than the Mercruiser controller, anyway). Whats the price difference between the 454, 502 and the 496? What are you planning on spending on mods for the 454? Are you turning the wrenches yourself on this one or paying for labor? :)

[rposton1]

The 502 sounds good to me, I like the fact that it has 415hp and forged pistons. Thanks for all your help Robert.:)

[OGShocker]

Originally posted by rposton1
The 502 sounds good to me, I like the fact that it has 415hp and forged pistons. Thanks for all your help Robert.:)
I think Walter has a 502ci/500HP.
Have you talked to him?
I met Walter after our boat was built. Had I met him before we would have a Marine Power unit in our boat.
my .02
OGS

[rvrtoy]

Marine Power has a 502ci 502HP that we put in a lot of our jet boats. This motor is probably the best bang for your buck.
They are also coming out with a 572ci 625HP motor, or so i'm told. I have 3 on order but have not received them as of yet.
Good luck:D

[rivercrazy]

Just be careful if you get the 502/502 crate motor. The cam is more of a street cam. Due to overlap you can pull water into the motor.

[rposton1]

thanks alot all! ....Robert:)

[Dave C]

If you go 496 then you get EFI. Thats worth at least $3,500 or more.
All you need to do is replace the pistons and some valve train to upgrade. In comparison to the price of EFI replacing pistons is no big deal.
Go with the newer techology.

[Chase]

Fuel injection rules!!!
Carb's suck..........:D :D

[Dave C]

tell me about it.
I am building a new 572 and it costs $5,000 for the EFI. ($3,500 parts plus labor)
Well worth it........:D
sea level, turn the key. 6200 ft, turn the key. No problema....

[rposton1]

I went with the 454 mag, thanks for all your help.:D :D Robert

[Mandelon]

The 454 part I get, but did you go with Marine Power or the Mercruiser?

[rposton1]

Oop sorry Its a Marine Power....Rob;)

[H20 Party Starter]

:confused: I talked to Walter this week for almost a half-hour on the phone. He is SUPPOSED To have a 572 motor in my buddy's boat by monday, finished by Friday. The check cleared long ago, and along with some other issues, My buddy is a little heated.;)
We'll see, these motor are supposed to be Bad-Ass, if Walter and his company can come through :(