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Ellen, is your 90HP Mercury four-stroke one of the recent models with EFI?

Thanks,

Ellen,

You're pretty close...... time to empty the boat when you ski now, how many people and what kind of weight was left in the boat....

I am pretty impressed. With the extra weight of the merc, and at 6000 ft..... that speed seems pretty good.

(not a big fan of merc altitude compensation, or the acute lack therof)

now if you had just taken that extra 100 off the motor and gone with the E-tec........... lol

congrats....... sounds like a fine solution.

I have an Etec 50 and it looses about 40-50% of its power at altitude. I took it to Lake Tahoe last year which is about 6000' and couldn't get past 10 mph, w/o ballast, granted 4 people on board and gear, food etc for a 3-day trip. I can get up to 20.5 mph with myself and my wife on board, no ballast, no gear, smooth water. No way would it pull a skiier, but a 90hp+ should do nicely. Other than the loss of power at altitude, I love the Etec, but I wouldn't think the 90 has any different technology than the 50 to compensate for high altitude. I heard that a smaller prop would be the only answer for this.

oops dup

Leon,

My comment referred to the E-tec, injection system, which does utilize a mass airflow, absolute pressure and manifold sensors which can suppposedly compensate somewhat both leanness and advance up to a density altitude of 7500 ft. (so waterskiing in nepal for you real zealots is still not going to happen with the 90.) This is measurably better than the jetted carbs or the non compensated injection/induction systems utilized by the nissan tohatsu, or the MAP system that Merc uses.

I have some experience in the nissan 50 hp at 4000 to 5000 ft. also..and have used another DI nissan at 3000 ft. you're not going to be satisfied above 3 to 4K.

That is why I wont buy another.....

The are rugged reliable engines...... but will not work the best in every place I want to tow my mac.

However, IF you want to get great fuel economy, stay at sea level, don't back up much, don't mind the noise and occasional slight smell, and dont want to pay as much, a 90 TLDI is VERY VERY difficult to beat.

oops dup

Never towed anyone with my Mac but always wondered how one would hitch up a tow rope without interfering with the rudders...

I normally have my M, which has an Evinrude 60 HP E-Tec, in the ocean at Marina Del Rey, where it will go 21/22 MPH with 2 people on board in smooth water. I did have my M at Big Bear Lake in southern California once (I live near there in Running Springs), which is at just a little over 7,000 feet. I didn't tow anything on the lake but I can tell you that I got 5,100 RPM's and about 20 MPH with 2 people and full ballast, and the boat was loaded fairly heavily (normal).

Rick

I'm not a skiier but at LOWISA 3 people took turns getting pulled behind us on a kite board. No problem pulling them up. The heaviest guy was 200 lbs. I have a Tohatsu 40hp. We had 3 adults on the boat and a bunch of stuff for cruising. I don't know how fast we were going while pulling the guy but without pulling anyone I think we could hit about 13 mph. This is close to sea level. On lake Granby (about 8500 feet) I think we can do about 11 mph. It was rather impressive passing all the boats that passed us in the race while pulling a boarder!

I did have a Tohatsu 50 hp TDLI before I downgraded (or upgraded) but it didn't work right even at Chatfield (5300 feet I think).

mtc wrote:but one can get up with a 50?

With the help of vgra-xd - - - YES!!!

Rick