Offshoreonly.com - 500HP's to 575's???

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Re: 500HP's to 575's???

Quote:

Originally Posted by WETTE VETTE

Merc's older 575's were 540's with solid tappet cams single plane intakes with 1050 Dominators. The de-tuned version of these was the 540 Bulldog. To get 575 HP out of the HP 500 should be easy and it could still look stock. Have JIMV port the heads and go to a different cam and bump the compression a bit and it should be there. As a matter of fact i think JIMV has a proven package for this motor that will get 600 HP on the dyno. Check his website.

Who is JimV ?

Re: 500HP's to 575's???

I do want the xtra 75-100 HP, but I always liked the look of the merc 575's. The blowers look sweet.

Re: 500HP's to 575's???

Mercury just discontinued the 575 because their 525 package was very close to the same HP and only used half of the fuel. The new Merc 600 produces more hp than the 575 while also getting better fuel economy. Considering this, are you sure you want to reproduce the 575? I would think aiming for the 525 efi would be a better choice - which I understand can be accomplished at a reasonable cost.

Re: 500HP's to 575's???

Are we talking about 575 SCI's or the older HP575's? Either way 75-100 more HP is attainable NA or with a small blower. JIMV is the owner of Valako Race Heads and he frequents this board. Here is his website. http://hometown.aol.com/valakoracehe...raceheads.html
I don't know the particulars about his 650 HP 502, but he is a good guy and knows how to get the most out of heads for marine applications.

Craig

Re: 500HP's to 575's???

Get a can of blue paint and go to it. :drink:

Re: 500HP's to 575's???

650 HP out of a 502 on pump gas will not happen.

Re: 500HP's to 575's???

650 HP out of a 502 on pump gas is possible, but it will require aftermarket heads and good headers. :D

Re: 500HP's to 575's???

I would just go with Whipples - make them 600's with low boost.

Re: 500HP's to 575's???

The Whipples would be awesome!! But if 600 HP is all he is after it would be cool to do it with stock looking NA motors. It also can help with insurance rates! :drink:

Re: 500HP's to 575's???

Insurance...
Factor the cost of insurance into your plans. If you add a blower and fail to inform your agent of this your insurance will be useless. Expect to pay a lot more for insurance with a blower. If you build a 540 and keep the engine appearance stock on the outside you have a pretty high possibility of keeping your insurance the same. Granted your insurance will still be no good but they will likely never know you have made modifications. In the event of a claim they are going to go over the boat with a fine tooth comb. It would be pretty hard for them to tell you built a 540 unless they tear it down. I suspect it would still be easier to get insurance if you tell them you did build a 540 but fudged a little on the rated power and speed.

I am sure some others who have looked into the insurance will have some other thoughts and I would be interested in hearing them as well. With the rate increase of a blower you can pretty well build a 540 with the savings on insurance over the course of a few years.