low_psi

Agree 1,000%. And not hard on drives either (as long as you throttle it back while in the air...)

Dave M

Shop for a fast hull first. Then you don't have to put big (unreliable) power in it to get the speed you want.

My hull is just shy of '32 LOA and runs 78 with a stock 525efi. Runs great in rough water too.

242LS

iTrader: (1)

I'm no expert, but I know there's a HUGE difference in how an engine will wear depending on the usage scenario. A car is low load, varying RPM range, and usually lower RPMs. A high performance boat is pushing hard through the water, usually spending a lot of time in a narrow RPM band, either cruising or going fast - and that's usually a much higher RPM than a car which shifts to higher gears/lower RPM on the highway.

glassdave

iTrader: (1)

be religious and fanatical about oil changes, drives and engines especially if they are new. I did my 525's every fifteen or twenty hours (thats actually more boating then you think). 280 trouble free hours and they ran like new when it went on to its next owner. I would have done valve springs if i still had it.

Orange quatro

I agree. I have a 496 HO in my Baja. Dam things are bullet proof. I have 350 hrs on mine and change the oil every season and outdrive every other never had a problem. Great enclosed cooling system. Same on the 525's.

On Time

I have stock 525s in the 42 closed cooling and change oil every 20-25 hrs with Merc semi syn 25W-40 and 330 hrs no problems. Start and run perfect every time. Merc rep told me 525s treated nicely will go a long time and knows a Formula cruiser with 800+ hrs no repairs only maintainance. My XR drives both needed lower gear sets at 250 hrs. Many 525s have had header issues with failed welds so be careful and professionally check out the headers if you get 525s. I have not had problems with mine but I don't use the boat in salt water or jump the props out of the water. Good Luck!

Pwraddr

Yea, 20-25 on engine oil, 45-50 on drives and changed before winter no matter the hours.

NautiNuff

OK, so the next level above XR's cost how much more? The HO's put out 375HP and a straight bravo is good for 400.

What do the 525's put out and what are the XR's good for? Bigger and stronger is good, but how much better for how many dollars ball park?

NautiNuff

Besides being a bigger motor, what makes the 525 a "racing" engine? What does it have the 496 does not?

glassdave

iTrader: (1)

the best annology to describe what our marine engines live like is they are on a full time dyno. We prop our boats to run at their peak power/rpm with the maximum prop. which is essentially a full pull at WOT (and some of us do that a lot ) I had to laugh when GM did their little marketing schpeal on the performance parts 572 where they said they put the motor on a pull turned the lights off and went home for the night. Big deal . . . . one of their truck motors off the assembly line can do that no prob. Heck some of the SV, SCL and SVL guys go a couple years at wide open throttle in a rough race environment and never have an issue. You also have to consider that your crank, while spinning, has a gyroscopic affect that makes it want to stay in one place meanwhile your engine block is moving radically through several planes. Yes . . . . . marines engines are impressively over built for a very dynamic environment.