I am thinking about upgrading the engines in my new boat. What are the pros and cons of the 525 vs.575. I am going to be running Arneson #6's. I was told that there is a good deal from Merc on leftover motors. At the price I am being quoted for the bigger motors I think I can't refuse. Anything I should be aware of on the 575?

As stock, there is not much difference in the actual HP between the two. I have heard from some good sources that the 525s are pushing out between 535 and 545 in some cases (there is a thread on this board as well). This was a dilemma when I bought my boat and based on all the people I spoke to, they said the 525s were the way to go because stock performance in my boat was only increased by two maybe 3 MPH., for a substantial increase in cost. My best friend has a 02 29 Fever with the 575 and there is basically no performance difference except the 2 MPH top end. Now he has messed with the boost a little and ECU and is seeing 86MPH. Quite higher than my 78-79. I guess it would boil down to how much they are charging for the 575s. Since Merc is discontinuing the 575s it might be a good time to buy.
I love the 525... and he loves his 575.

Chuck, Go with the 525's Ive been doing my homework on this one and almost every person reccomends the 525 over anything else out there

Give me a call

361-6521

Thanks for the input Masher44, Troutly, and Otis. Not to really throw off the question, but what are your thoughts on the new Merc 600? Otis, hows Florida?

I think ottis is leaving for FL tomorrow Morning.

A buddy has an Outerlimits 37 with 575's he changed pulleys and reprogramed the ECU pushes his rig to 93 rated around 675 now. To get that out of your 525's you might have to spend somewhat more.

Ohh yahh, blower whinnne kicks azz. Remember in May!!!!!

My sentiments exactly

My vote would be to buy the 525 bolt on a whipple supercharger keep the closed cooling system and run all day long with 93 octane at around 780 horsepower each. That sounds like a pretty nice package bolted in front of arnesons !!!!!!!!!

Oh yeh those puppies sure look pretty

If you're going to swap out motors why go with Merc at all? There are a lot of high quality builders that will out perform merc at half the cost. So go buy 4 and you'll always have spares.

If it is a choice I would go with the 525's. My 575's have been a real battle but I think I'm going to win the war.

As with all motors, be careful who you get them from. Too many people out there selling junk. and doing crap work.

I agree that Merc's pricing is crazy, but I had a bad experience with aftermarket high performance motors before. I think I'm going to stick with my 525's or posssibly see what Nor-tech's pricing on their 625 package is. I'm not really swapping out, this is a new boat being built right now. Thanks for you input Mr. Velocity.