Thanks Eddie, sounds about right.

Steve,
I don't see why you couldn't fresh water cool it. The biggest hurdle would be the packaging. That's a pretty busy engine, so you may have to end up putting the heat exchanger in the boat some place. There are a few aftermarket companies that make DIY closed cooling systems. I doubt anyone makes a specific bolt on kit for the 850/1075, but I would think a "kit" could be put together from individual parts.
Eddie

Why would you ever want to detune an 850?

With the new advancement in lifters..they will last...

Monitor Industries in Florida builds the closed cooling for the merc engines I believe.

Mercury already makes a kit (almost positive although never heard of anyone running it) (Monitor Industries) to adapt to the 850 and the 1075sci, it's an option. I'm trying to find where I saw it in the parts manual, I was shocked to see it the first time I ran across it.

All in all Eddie will not steer you wrong.

Jeff,

The exact price will depend on the components used. In order to convert to hyd. roller, you need to change the camshaft, lifters, valve springs, retainers, locks, valve seals and pushrods. I would also change the timing belt while I was there. For the parts, you are talking about $1500-$1600. Like I said, the exact price will vary based upon the exact brand of parts that you use. The labor would depend on a few variables as well.....are the engines in or out? What other items you want to do as well, etc.???
Eddie

If you only want 850hp, this is very easy. You can put a hydr roller in there and not sacrifice a thing and you can easily get 300 hours out of it. The 1075 is similar, but you will lose power. I don't care what anybody says, solids make more power. I've done many back to back test with equal specs on lift/duration. At this power/lift/duration level, the solid is worth 30-50hp pretty much across the board and more significant as the RPM exceeds 6000. So, it can be done, but you'll be closer to the 1025-1050 range.

You can easily detune the 850, or make 850 on 87 octane with some cal changes.

The lower end of the engine can well exceed those parameters so the valve train is technically the only thing that needs the short service/rebuild time.

Get hold of Bill Steppi/sutphen30...he isnt far from you and has a mass hole accent too...he can get you set up properly.

Will make you a good deal on a 06 42 Legacy with 1075s. No time to use it. Still has less than 140 hours on boat. Motors gone through at 100. PM me if interest.

I met Bill about a month ago.Did a season end Poker Run.Good guy for sure.I'm still trying to finalize the sale on my boat.Certainly appreciate all the interest in the thread.Probably should have titled it "How to get 700 type longevity out of 850/1075's??"Just checking my options.Seems to be some good deals on the big power packages. As far as Mass Hole,I resemble that remark!
Jeff

I have used Monitor Marine they are local to me, good company.
Steve

i built my 700+hp engines in 2006.these engines have never been out.you don't need a lot of cam for those numbers.
my engines will be available after i build some turbo ls motors.going to the bone yard to find some canidates on saturday.i needed a winter project besides the 1300hp 581ci whipple motors.