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-   -   CMI on 496 HO with Captain's Call (https://www.offshoreonly.com/forums/cobalt/182544-cmi-496-ho-captains-call.html)

no replacement 03-20-2008 07:12 AM

CMI on 496 HO with Captain's Call
 
Thinking about having CMI's installed on a 496 HO with Captain's Call in a 220 with B3x.
Anyone have experience with a similar set-up?
Concerned about fit, props, etc.
Thoughts?

tblrklakemo 03-23-2008 10:40 AM

IMO....save your money. They will be a pain in the azz to get to fit. Ive seen the work required when put in a 23 outlaw with a mag. Rarely a direct fit. Sound good? Hell ya. Notice much diff in the seat of pants? Nope. 4-5 grand is a lot for just sound. As for props... on a reg b1 if you are on the limiter right now you could go up a pitch and probably be ok. DOnt know much about b3's.

Do it right and Spend another 5k+ the cmis and get some raylar stuff too...open up that intake also. That'll get'r dun.

no replacement 03-23-2008 12:04 PM

F F Enthusiast,
Thanks for the note
I see a lot of positives on this site about Raylar.
From somewhere ( Powerboat?) I read a B3x ( on my boat ) is good to about 65 MPH and can take somewhere north of 500HP.
I have not heard a 496 with CMI's, I don't think. Bet its awesome.

tblrklakemo 03-23-2008 12:23 PM


Originally Posted by no replacement (Post 2496161)
F F Enthusiast,
Thanks for the note
I see a lot of positives on this site about Raylar.
From somewhere ( Powerboat?) I read a B3x ( on my boat ) is good to about 65 MPH and can take somewhere north of 500HP.
I have not heard a 496 with CMI's, I don't think. Bet its awesome.

Its not that I dont like any of the options on their own, but its a lot of money for very little. Combine them and you will get what your after......that was their design in the first place imo. The x drives should take 500hp reliably and easy on them. Ive read the same on the b3's.....input hp isnt the problem. Its excess drag created from the duo-p design at speed. I would think you should be fine in the 70's. I know volvo puts their duo on their dpx600 motor that makes something like 600hp. Ive seen pairs of those in hustlers and some other boats that do over 70 easy. Yes, the cmis do make the 496's sound like they should. Considerably more bark in the sound. Id love'em too if somebody gave me 5g's.

Elite Marine 03-24-2008 04:37 PM

2 Attachment(s)
There are proven performance gains and you sure cant beat the look!!!

no replacement 03-24-2008 08:30 PM

Thanks Pantera.
Those are probably the same or at least similar dyno data sheets I've seen before so the performance is real to me. My greater concern is fitting CMI's in with Capt's Call and what prop set to move up to in a B3x.
I'm not convinced , quite yet, it is a simple matter, but hey, thats why I'm askin'.

Elite Marine 03-25-2008 04:17 PM

The 496 Kit with Corsa is not an issue at all, we have sold many.

As far as upgrading props for the B3 I have no experience with it.

Knot 4 Me 03-26-2008 09:15 AM


Originally Posted by no replacement (Post 2498129)
Thanks Pantera.
Those are probably the same or at least similar dyno data sheets I've seen before so the performance is real to me. My greater concern is fitting CMI's in with Capt's Call and what prop set to move up to in a B3x.
I'm not convinced , quite yet, it is a simple matter, but hey, thats why I'm askin'.

How many RPM's are you turning today at WOT with a light load? What pitch B3 propset are you currently running? With the addition of the CMI headers, you may have to send you existing set off to BBlades to be tweaked or may have to move up to the next size pitch in props. Just depends where you are at RPM-wise now and how your hull reacts to the additional HP.

pasquesi 03-26-2008 09:40 AM

I owned a 23LS. Mine had a Volvo Penta 8.1 HO, with a DuoProp drive. Essentially the same horsepower and setup as yours. Bone stock with a light (6") chop, top end was 56-57 MPH GPS. I was running a F7 propset, occasionally bumping the rev limiter. Mine had the Captains Call as well.

I installed the CMI headers, and reprogrammed the ECU. Installation was not easy at all. The sound was louder and more sharp. Performance gains were definite. I replaced the propset to a F8, because the F7 was all over the rev limiter. Getting on plane took WAY longer however, with the F8. Top end increased to 61-62 MPH GPS.

In the end, for me it was not worth the money. My opinion is that a DuoProp or B3 drive is not designed for high performance applications. Unless you have the DPX, which Volvo doesn't make anymore. Also, the Cobalt hulls don't do well at more than 65 MPH.

I know the CMI product does what it says, but The Cobalt hull will be very resistive to higher speeds, no matter how much power you throw at them.

no replacement 03-27-2008 08:13 PM

Hey Pasquesi,
I tend to agree with you about the hull and B3x. Fine to 60 maybe a bit more, questionable to push it much past and w/o hydraulic steering for better control.
Thanks for everyone's input.


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