Hi,

I have a 2006 Baja 242 Islander with a 496 in it producing 375HP geared to a Bravo 1 drive. I have been considering upping the motor and drive but I'm getting a bit overwhelmed with my options. I have considered a Mercruiser 525 geared with a Bravo 1 XR. As I research more I'm now considering Cobra Power and Chief engines, both in the 570-700hp range. I'm looking for more speed and better torque. Would anyone have an idea as to the increase of the top speed? I've heard a gouge of 1mph for every 13hp?

Currently the boat runs 58-60mph on a Mercury High 5 prop at 23P.

I'm looking for any feedback and suggestions. Right now it's more of a fact finding period than anything.

Thank you,

Jim

Hydraulic steering first.

Yes you are correct about the HP per mph. With your boat being lighter 13-15 per MPH. Generally 15-20 HP per mph Is what I have been reading the last few years.

Have you tried swapping props first? Perhaps Mirage plus 25 pitch? A high 5 should give you a good hole shot and cursing speed, but not good top end. There's always a trade off.

A fellow boater has a 232 islander with 310hp 454 and he runs 59 on GPS with a light load. He is spinning a mirage plus 23. With your added HP a 25 should be no problem. Perhaps a labbed 25. Also look at the bottom of your hull, you see that hook there at the transom? That is a HUGE trim tap in the down position, that is slowing you down.. Might want to have the hull blueprinted.

The 242 is like a 22' hull your going to have your hands full with a 525 in that hull. Definitely want hydraulic steering if your putting that kind of power in a single.

+1 on the high five prop being a speed killer on that boat. A low hour 525 prolly cost as much as the boats worth. You'll end up spending a "small" fortune. Just the required steering upgrade will be a few G's, none of which will be realized at resale.

You can get several MPH more than your current numbers with the right prop. I'd spend the rest on Whiskey, women and fuel.

I have the HO in mine and with a 3 blade 23p bravo i saw 65mph on GPS. it was a handful at WOT. I switched to a 24p 4 blade and dropped down to 63mph but can run WOT all day and much better whole shot. I have yet to find another 242 with a 496HO in it. Im trying to find a 26p just for testing, but havnt been able to find one someone will let me borrow.

[QUOTE=Hook'em;4039687

I'd spend the rest on Whiskey, women and fuel.[/QUOTE]

Thank you all for your input. I put the thought of re-engining on hold during the holidays. Now that we are in the dead of winter I have the itch again.

I'm running the High 5 purely for water sports. I have a 3 blade 23P that came with the boat but I found my hole shot was not that great, hence the additional purchase. It is my understanding that there is a kit from Mercury that can up my 496 to 425 HP similar to the HO model for around $3K. I've seen ads for headers that claim an extra 46HP for around $3K as well.

Irishtornado, can you educate me on the need for hydraulic steering if I go to the 525?

Has anyone worked with Cobra Power and if so, what has been your results?

Finally, my last time out this season I was not getting full WOT. A talk with my mechanic and a visit to a Mercruiser repair center and $2.5K later my fuel cooling module was replaced. Mercury is well aware of this problem (paint coming off of the inside of the module and jacking your fuel system) but takes no responsibility for it.

Thank you all again. Any additional input would be greatly appreciated. Happy New Year!

James, please explain this more. I've never heard of it. How did you find it and what were the symptoms of the problem?

Dan