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-   -   Best way to get 600+ HP??? (https://www.offshoreonly.com/forums/general-q/215817-best-way-get-600-hp.html)

B_Schutz 08-27-2009 09:59 PM

Best way to get 600+ HP???
 
:readinghelp:My boat has a all stock 380HP 454 Mag EFI with thru-hull. What is the best way to get a reliable 600+ HP. I originally thought of a procharger, but have been thinking of pulling my 454mag and just poking in someone elses crate motor. I have no problem building a motor, but is a 454 bowtie block a good foundation to build a reliable motor, or should I get a big CID motor with more torque?

dogturd21 08-27-2009 10:04 PM

procharger, whipplecharger...I like that idea. I have never seen a procharger with a closed cooling system though (just wondering to myself).

Nordicflame 08-28-2009 07:32 AM

If your motor is a 454MAG EFI the block is not a Bowtie.
The only naturally aspirated Merc motor with a Bowtie block is the Bulldog. The Mag EFI is a standard Gen VI block.
That doesn't mean it's not a good foundation for a 600hp motor though. You could start with a 4.25 stroker assembly and a good bore will make a good 496 stroker motor that some here have made some really good numbers with.

Dave

B_Schutz 08-28-2009 07:51 AM

I thought there would be more guys pulling for sticking in a crate motor than building one from my 454.

Nordicflame 08-28-2009 08:06 AM

You just have to weigh the cost and end result your after.
Using yours is just one option of many as you'll find out here shortly :drink:

laszlo01 08-28-2009 09:11 AM

Talk to dean gellner aka Mrhorsepower1 on here, you can make a nice n/a 540 out of your gen VI with some dart pro one heads and get 650 HP out of it. Just my 2 cents

jeffswav 08-28-2009 09:28 AM


Originally Posted by laszlo01 (Post 2941517)
Talk to dean gellner aka Mrhorsepower1 on here, you can make a nice n/a 540 out of your gen VI with some dart pro one heads and get 650 HP out of it. Just my 2 cents

You need a 502 block to make a 540.

jeffswav 08-28-2009 09:32 AM

Here is what I did. I started with a 454 bored and stroked it to a 489. New exhaust with long risers (no silent choice), RMbuilder custom cam. Good reliable 500HP. If you want more sell what you have and drop in a 540 or 572, start with a Dart or Merlin tall deck. You can easily build 600-650HP with that.

Wahoo ATV 08-28-2009 09:33 AM

buy a 525

SkiDoc 08-28-2009 11:17 AM

Sell what you have and start from scratch, been there. I did the Procharger and had good results with it but you will be better off starting from scratch with a 540. I added blowers, heads etc to some carbed 454 mags with good results. Both are options, but the 540 will be cheaper and more reliable down the road. A lot of stuff will have to be changed to do the Procharger right. If you build your 454 into more you will have a bunch of parts that you will have to give away. Again start from scratch and build it right.


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