290 Sundancer Performance

[rowekmr]

Hello Group
I just picked up my 290 from the shop after getting drive work, gimbal ring replacement (many hours), tune up incl all filters and other misc work and while going down the river I noticed that at WOT I got about 37-38 mph on the GPS. I didn't get a chance to check the exact rpms but I know it was over 4000 and have to see what props on it. It had about 3/4 load of fuel and me does this seem normal? I figured it would be at least in the mid forties with twin 5.7 EFI's and Alpha I (Gen II) 1.62 drives.

Joe

 

[Lazy Daze]

Ummm... 1978 model year? 1998? :smt001

Either way, doesn't sound out of range at 4,000rpm. Are you saying this is different than before you had it into the shop?

You mentioned "going down river". Were saying that generally-speaking? Or were you actually going "up" river against the current?

 

[rowekmr]

Oops sorry forgot to mention it is a 1999 model. Before I put it in the shop I did not go faster than a slow cruise I was told the gimbal ring was in bad shape plus the bellows were in poor condition (replaced all on starboard engine).

"Down" river is a local term because I was going from the river to the lake. There is negligible current on the river so for all intents we count it as no current.

I think the WOT rpm's were about 4400 but was caught up in the excitement to really make a mental note of them :grin:

Ummm... 1978 model year? 1998? :smt001

Either way, doesn't sound out of range at 4,000rpm. Are you saying this is different than before you had it into the shop?

You mentioned "going down river". Were saying that generally-speaking? Or were you actually going "up" river against the current?

 

[rowekmr]

Also Dennis on a sidenote how does the diesel run. I have been wanting one for awhile and some naysayers talked me outta buying a Suburban diesel and bolting on some mods that are available for increased power. I notice a few are also burning old vegetable oil. I ended up with an Excursion for 2 years that I sold and I just picked up a 99 Burb with the 7.4l for occasional towing duties (travel trailer and 26' boat).

 

[Walz]

With my 4.3's I get in the low 30's, so that sounds about right. Really depends on the props.

 

[Southpaw II]

My 290 DA had the same setup, but was a 1998. New, it ran an honest 45 mph @ 4500 rpm. 6 years later, with the original bottom paint, when it sold, it ran 40. Check it with a clean bottom, and take home all the junk stored on board and in all the lockers.

 

[rowekmr]

I am suprised I remember the 280 DA's with 5.7's when they first came out doing high 40's unto the 50's on the boat reviews. I do have Alpha I's vs the Bravo III's or II's and wonder does that make a difference. My buddy has a 290 Amberjack and he claims to do 52mph (I remember it doing 40 at least) but he has BIII's and just got his props reworked. I will check my props next time it is out of the water (hopefully not too soon [repairs]). It was just put in the water so it can't be bottom growth but it does have a very thick layer of anti foul paint on it so don't know if that cost is some mph's. The drives are both new (now that's another story) and the engines both tuned up so I guess this is where I am at for now. Thanks for all the input.

 

[comsnark]

Sounds low.

How were tabs set?

How was drive trim set?

How clean was the bottom?

What condition are the props in?

My boat moves at 35mph in November, 46 in May. Bottom is always prestine. Props are clean in May, ugly in November.