HP sizing on Chap 23 SSI

catawimarine

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We're considering a Chaparral 23 SSI. Two Mercruiser engines are offered: 4.5L (v6), and 6.2L (v8). My plan was to order one with a 6.2L, but Chaps are hard to come by now, and we have to wait. I found one that has a 4.5L, and it looks like it has just about everything else I had envisioned. The question is: am I going to regret waiting to buy one with a 6.2L?

It's worth noting that all of our boating activity is on freshwater inland lakes; we normally have 5-6 people on board; the kids are into water sports (wakeboard, and 2-up skiers, and tubing.)
 

tpenfield

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Welcome tyo iBots . . .

Yes, you will regret waiting, if you buy the one with the 4.5L
 

JimS123

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Several U-Tube videos are available to view. Boating Mag reviewed that boat, and it had a Volvo V-6 240 HP I/O. If you look at boats for sale, they all are equipped with a V-6, so that must be the price point that dealers are trying to achieve.

49 mph ain't too shabby. With 5-6 people you'd probably want to upgrade to a better prop anyway. If you don't mind the extra $5K, go for the V8. It don't hurt to be the fastest boat around.

If it were my choice and I wanted the best performance I would take the $10K upgrade and go with the outboard version. After going OB you'll never come back...
 

catawimarine

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I guess I didn't ask the question quite right: will the 4.5L be a disappointment to me, and will I regret NOT waiting for the 6.2L?

To answer a few points already made, and add some more details:

We do have an older (1989) runabout with a 4.3L v6 Merc (alpha one), and we've been boating for about 15 years. Our experience has NOT been running at top speed and pushing the our boat all that hard in terms of high speed running. My main performance concern is probably more along the lines of a quick hole shot, and enough power to pull 2 fat guy skiers at the same time. (Our older boat can do this, but it does work little bit at getting them out of the water.)

I can afford the more expensive 6.2L, but my sense is that if that's the "right" thing to do, we're going to have to wait until the summer of 2022 to use a new boat. I'd rather not wait if it's only going to be a negligible difference.
 
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JimS123

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Our last boat was capable of a V6 but we opted for the little 3 liter 140 HP I4. Everybody poopoohs that motor and says its underpowered, etc. I could put 8 people in the boat (a butt in every seat - 4 adults and 4 pre-teens) and that boat would still jump out of the water. My son bought almost the same model with the V6 and truthfully we would go neck and neck and you thought we had the same engine. He had the factory prop.

Most any boat will perform well if its propped right. You can make it jump out of the water and zoom to WOT in short order if you are willing to lose a few mph at top end.

To answer your question - my guess is that you WILL regret the 4.3. Surely one of your buddies will buy the V8 and when he passes you on the lake you will be disappointed. Only you can know what is "negligible". Ask Chap for performance curves. Nothing like looking at data.
 

Scott06

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23 ft. boat I’d hold out for the bigger engine.

My good friend has a 24 ft deck boat , one he bought new after it sat at the dealer, got a great deal etc... Has a 350 mag with 300 hp. It is adequate at best, needs a fair amount of throttle to stay on plane.
 

JimS123

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It is adequate at best, needs a fair amount of throttle to stay on plane.
That's the simplest fix there ever was. The problem is that when the manufacturers sell a boat they set it up for max speed at min weight. That way their performance curves look good. Trouble is people don't use boats that way.

The only boat I ever bought that came optimized from the factory was a Boston Whaler. But then again, the optimized performance was reflected in the price.
 

Scott06

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That's the simplest fix there ever was. The problem is that when the manufacturers sell a boat they set it up for max speed at min weight. That way their performance curves look good. Trouble is people don't use boats that way.

The only boat I ever bought that came optimized from the factory was a Boston Whaler. But then again, the optimized performance was reflected in the price.
Unfortunately with a bravo iii repro is an expensive hobby. i think a set of 4x4 props like hill marine would help. Reality is it should be had a 6.2 ....
 

JimS123

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Unfortunately with a bravo iii repro is an expensive hobby. i think a set of 4x4 props like hill marine would help. Reality is it should be had a 6.2 ....
I think I paid 600 something when I upgraded to my Enertia. Of course, it was a single, not a duo. Nevertheless, the improved performance was worth the cost.
 

catawimarine

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Thanks for all the discussion here - it was a help to me. I was able to locate a dealer with a one custom build left, and we reached agreement on a new boat with a 6.2/v8. So, that's on its way with a projected early June delivery.

With all of this discussion of correct props, where would I go to get a primer on those issues? A bit of background: our 4.3L/v6 (Alpha One) came with two different props, and I've used both of them at various times. To be honest, I haven't carefully compared them in the water, and I couldn't tell you which one is "better." I believe one is a 19 pitch prop, and the other one is a 21 pitch prop.
 

mr 88

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Thanks for all the discussion here - it was a help to me. I was able to locate a dealer with a one custom build left, and we reached agreement on a new boat with a 6.2/v8. So, that's on its way with a projected early June delivery.

With all of this discussion of correct props, where would I go to get a primer on those issues? A bit of background: our 4.3L/v6 (Alpha One) came with two different props, and I've used both of them at various times. To be honest, I haven't carefully compared them in the water, and I couldn't tell you which one is "better." I believe one is a 19 pitch prop, and the other one is a 21 pitch prop.
Should be pitched properly from the factory . You really can't go shopping for props until you have used the boat for awhile and see how it performs. With a normal/average load of gear ,people and gas open it up and compare the rated max RPMs and what your achieving. That is your base line when trying to upgrade your performance . Good move with the V-8 , your going to have a lot more torque to pull skiers out vs a 6 banger. Even if the speeds are close between the 6 and 8 the 8 has a lot more towing capabilities with out bogging down. The 6 is at its limit when they tweakevery HP they can out of it, the 8 is not and in theory will outlast the 6 as it is not being worked as hard. Fuel mileage will be the same if cruising at the same speed. Good luck.
 
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