1985 Contessa top speed-gctid820988

[Contessa2850]

I recently bought a 1985 contessa 2850 with a vp260 engine and a vp290SP drive. I have only been able to consistently get about 20mph even on a flat day. The highest i got was 23mph. All on gps. The engine doesnt get over 3000 rpms at all when driving. In neutral it will rev to about 4500-5000 rpm. It seems to be planing off ok but only on a flat day on the water. I have tried messing with the tilt and trim and really hasnt made much of a difference but i feel like the engine should be getting more rpms at wot. I dont think its a linkage adjustment because in neutral it will scream around 4500. Does anyone have any suggestions or is this just the best it will get?


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[2850Bounty]

Things to check:

Cylinder pressures

Ignition advance .... both Progressive and TA

Fuel delivery system

Hull bottom for marine growth

Condition of propeller

Make sure that the boat is not stern heavy!

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[Contessa2850]

Hull is freshly painted. Prop is in good shape though not sure if it could be the correct one but it seems fine looking at it. It is 30 years old and im not the original owner so who knows if it is correct. Im not familar with what should be on there or how to size them. The engine starts and runs perfect only the issue with rpms at WOT im gear. It has a new fuel tank and fuel filter. In neutral it gets right up to 4500rpms. It definitely is a heavy boat and may be a bit underpowered but i still think i should be able to get more rpms at WOT. But i could be mistaken.

[2850Bounty]

are you able to answer these questions :

....What are your cylinder pressures?

....What is your ignition advance doing ...... Progressive and TA?

....Did this boat reach WOT RPM during your sea trial?

....Which prop was used during your sea trial?

By the way....... it's RPM (no S needed)!

[SKUA_28_Contessa]

32 is quite possible, and a tad bit more on a good running 350. Just because it will rev to 4500 in neutral doesn't mean much. I would echo Bounty's questions, What prop do you have? An OEM "elephant ear", 16 diam. x 13 to 16 pitch is usually the correct range choice, for single prop, 350.

[Contessa2850]

Can anyone tell me what this litte box is that is next to the coil? Also it has a stock volvo penta distributor probably original. Im wondering if the mechanical advance isnt working. I have no means of testing it to see. It does have a pertronix electronic ignition though which looks to be a conversion from the points.


Attached files

[SKUA_28_Contessa]

Ballast resistor for the ignition system, usually used with points, not electronic ignition systems. Won't hurt anything unless it goes bad, then no start. With electronic conversions, It's eliminated, But I never did a pertronix conversion kit. Their reputation amongst auto enthusiasts isn't very good.

[2850Bounty]

From the looks of the distributor cap, it looks like an old Prestolite distributor. It could have points or it may have been converted.

If you want to check and see if the progressive advance is working, continue strobing your timing marks as you increase RPM.

If it is working, you should see a smooth and steady increase in advance up to approximately 28┬░ at 3,200 RPM.

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