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I am SO excited to own this boat and find this forum! She has been stored indoors, under cover since being purchased new and I am just the 3rd owner (the 2nd owner had it nearly 40 yrs). Structurally and cosmetically in great shape, and just over 300hrs.

With a sterndrive Mercruiser 260, I am curious what others have done to either upgrade the engine or replace altogether. What would YOU do?

She ran great at the Delta in CA, but then at altitude in Lake Tahoe, even swapping out the prop, she struggled to go (while looking pretty sharp on the lake).

Thanks in advance for any help!

Benjie

Welcome from the California Delta as well.
That’s a super sharp 19CD! And yeah your going to give us more interior pics… the red is so cool!

Let’s remember Tahoes Density altitude and true changes to air fuel will never be right so as long as you prop swap just enjoy the day.

Those early year outdrives weren’t really designed for much more torque so baby steps.
1. Camshaft change ( comp cams marine )
2. Intake and upgrade to marine 4barrel

You may pick up a few cruise speed mph with a pitch add on the prop at sea level.
If it has exhaust through transom it will sound fast.
Give us your captains report on your current setup and speed vs rpm.

Myself I would do a 8.2 bb in her

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Hey benjie. So glad you found us!

Amazing she only has 300 hours on her for that age. Nice find.
I agree with matt above. You could also try a wake foil on the outdrive to help in planing. Quick inexpensive solution for under powered boats.

Thanks for the pics and welcome aboard mate!

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That is a beautiful classic in what looks like showroom condition - congrats!!!. They would love to see this at the classic Regatta.

cmattj wrote: Wed Dec 08, 2021 6:43 am Welcome from the California Delta as well.
That’s a super sharp 19CD! And yeah your going to give us more interior pics… the red is so cool!

Let’s remember Tahoes Density altitude and true changes to air fuel will never be right so as long as you prop swap just enjoy the day.

Those early year outdrives weren’t really designed for much more torque so baby steps.
1. Camshaft change ( comp cams marine )
2. Intake and upgrade to marine 4barrel

You may pick up a few cruise speed mph with a pitch add on the prop at sea level.
If it has exhaust through transom it will sound fast.
Give us your captains report on your current setup and speed vs rpm.

Thanks for the tips. It looks and sounds great.
Last summer on the Delta - 42.5mph @ 5k rpm:
Swapped the prop for Lake Tahoe and I could not get over 2500rpm... not an enjoyable day. Actually the reason I looked around for some help and found this forum.
Returning with the same prop set up, but running on the Delta - 35mph @ 4.5k rpm:

Unfortunately, this is my first boat (my dad had a late 70s/early 80s Fresno jet boat - I learned to ski and drive my teenage years) and I am a novice when it comes to these engines. But hey, I'm willing to learn!

I was not sure if I would try and use the small block, upgrading to a new carb / injectors, replace the whole engine, or? ... in a bit over my head here.

I've also moved from CA to Idaho and can't wait to get her on some nearby lakes next summer, if I can solve the engine.

Some additional pics (hope the links work):

Nearly new classic skis came with the boat! Check out that O'Brien international exhibition comp ski - hardly used:
very red interior


In case imbedded pics don't work:
https://photos.app.goo.gl/gBtX9e92fR73f42CA
https://photos.app.goo.gl/crLoEg6FCzhM6ExH8
https://photos.app.goo.gl/KY9mDgzgSS25icA79
https://photos.app.goo.gl/Yb17rgXgaH6B1PPH6
https://photos.app.goo.gl/YXreGWZonbu4yfBbA
https://photos.app.goo.gl/NrgCSYeoMZz4bhkj7

I figured out how to attach pics.

Also included a before pic of my trailer refurb work.

Looks great!
It appears you may have a 4 brl Quadrajet on there so that’s a start.
They are metered rich for marine use and prone to leaking at the base plate fuel transfer plug which can make them idle very rich.

As your going to a medium elevation area (3000 ft) you will be down on power again , along with fuel richness which can add to the laziness.

Your Tahoe prop should be a start along with a idle mixture adjust ( lean it) for your baseline.

Find a marine shop in your area that can spell Carburetor .. to get you set .

As 45 mph is very good at sea level it appears all is healthy!

cmattj wrote: Thu Dec 09, 2021 7:34 am Looks great!
It appears you may have a 4 brl Quadrajet on there so that’s a start.
They are metered rich for marine use and prone to leaking at the base plate fuel transfer plug which can make them idle very rich.

As your going to a medium elevation area (3000 ft) you will be down on power again , along with fuel richness which can add to the laziness.

Your Tahoe prop should be a start along with a idle mixture adjust ( lean it) for your baseline.

Find a marine shop in your area that can spell Carburetor .. to get you set .

As 45 mph is very good at sea level it appears all is healthy!

Matt What exactly is this carbonation thing your talking about?

Big Block Power wrote: Thu Dec 09, 2021 12:03 pm Matt What exactly is this carbonation thing your talking about?

Right?! Now a carburetor is only thought of on a bong .
So I’ve read

cmattj wrote: Thu Dec 09, 2021 1:35 pm

Big Block Power wrote: Thu Dec 09, 2021 12:03 pm Matt What exactly is this carbonation thing your talking about?

Right?! Now a carburetor is only thought of on a bong .
So I’ve read

cmattj wrote: Thu Dec 09, 2021 1:35 pm

Big Block Power wrote: Thu Dec 09, 2021 12:03 pm Matt What exactly is this carbonation thing your talking about?

Right?! Now a carburetor is only thought of on a bong .
So I’ve read

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And here I thought you were talking about the Carbonaro Effect.

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