Author Topic: CVX 18 Prop  (Read 11460 times)

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Offline still_fishin

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Re: CVX 18 Prop
« Reply #20 on: August 31, 2012, 12:45:02 PM »
Get your a-- to Red Wing and you can try my turbo!
'80 Intimidator
'85 CV23

Offline fireman24mn

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Re: CVX 18 Prop
« Reply #21 on: August 31, 2012, 12:53:40 PM »
you sound crabby go back to sleep and I will see you this evening
I think this has become an addiction.


1977 CV-23 I/O Full Resto complete
1976 CV-16 V8 Resto in progress
1985 Pearson MotorYacht 43ft

Offline fireman24mn

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Re: CVX 18 Prop
« Reply #22 on: September 03, 2012, 08:35:28 PM »
So I tried Tim's Turbo 23p and I am still at 60mph with about 4,900rpm So the search is still on. I would like to run WOT at about 5,400 rpm Anyone have any other suggestions for Size and Pitch
I think this has become an addiction.


1977 CV-23 I/O Full Resto complete
1976 CV-16 V8 Resto in progress
1985 Pearson MotorYacht 43ft

Offline OleRed

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Re: CVX 18 Prop
« Reply #23 on: September 03, 2012, 10:33:43 PM »
http://www.getaprop.com/content-product_info/product_id-9455/powertech_ofx_3_propeller_mercruiser.html

I'd think you should try one of these babies, I'd guess your speed lower 60's @ 5200/5300
I plugged it into the prop & speed calculator @ 5300 rpm 63mph with 11% slippage, which is pretty good.
what the prop calculator don't take into concideration is performance prop mods, like cup, rake, and diameter,
but this new style PowerTech is the best performing prop I have run.
But .. keep in mind that if you want to turn that much rpm, just do it for short bursts, the Mercruiser drives don't like extended runs at rpms over 5000 .. heats up the upper gear case, not good
« Last Edit: September 03, 2012, 10:50:58 PM by OleRed »
1980 23ft Scimitar

Offline fireman24mn

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Re: CVX 18 Prop
« Reply #24 on: September 04, 2012, 08:10:05 PM »
Red what pitch are you thinking? 23? Also what Diameter?
« Last Edit: September 04, 2012, 08:14:45 PM by fireman24mn »
I think this has become an addiction.


1977 CV-23 I/O Full Resto complete
1976 CV-16 V8 Resto in progress
1985 Pearson MotorYacht 43ft

Offline OleRed

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Re: CVX 18 Prop
« Reply #25 on: September 04, 2012, 10:21:24 PM »
I'd suggest the 15 1/4 diameter with 21 pitch
1980 23ft Scimitar

Offline fireman24mn

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Re: CVX 18 Prop
« Reply #26 on: June 13, 2013, 06:49:46 PM »
Picked up a 22P lazer2 for 125.00 today I might even go get the 18 this weekend so I can try it out.
I think this has become an addiction.


1977 CV-23 I/O Full Resto complete
1976 CV-16 V8 Resto in progress
1985 Pearson MotorYacht 43ft

Offline David CVX-16

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Re: CVX 18 Prop
« Reply #27 on: June 13, 2013, 09:14:54 PM »
Check the hub diameter on your 22" Laser II to see if it fits your gear case. The even pitches are for the small hubs, and the odd pitches for the larger hubs.
David
87' CVX-16, 85' 115 HP Johnson, 58.8 MPH GPS w/ 23" SRX Prop

Offline Villager19

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Re: CVX 18 Prop
« Reply #28 on: June 09, 2019, 02:21:05 PM »
This is an old thread but looks like a good one... so I hope everybody is OK if I add to it rather than start a new one.

My 1979 CVX 18 has the stock Mercruiser 305 228/Alpha 1 configuration, aside from a recent upgrade to an electronic ignition. My exhaust is just a straight tube now (no bellows, more on that later).

With a 4-blade Mercury Spitfire 14 x 21 I am getting max speeds of 50-52 mph regardless of passengers/fuel and otherwise somewhat smooth boating conditions (wind, water etc). The boat is maxing out at those speeds just a shade over 4,000 rpm.

Does this seem about right?

It sure gets out of the hole fast and corners like I'm in a movie.

I won't be pulling skiers, mostly cruising. Are the suggestions above still good if I'm looking for more top end? Any new ideas?

Thanks in advance!!
Illinois Dave

1979 Glastron Carlson CVX-18
2014 Crownline 215 SS

Offline Plugcheck

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Re: CVX 18 Prop
« Reply #29 on: June 09, 2019, 03:49:17 PM »
50-52 mph seems low, but it's the rims that seem more concerning.  Your wot rpms should be around 4600-4800.  Try a smaller diameter 3blade in 21p.  Prop testing is an artform all its own.  Best best is to find a shop or friends that will let you test different props.
Michael
1979 CVZ-18 388 CI Vortec Mouse
1980 CVX-16SS 140 Mercruiser
1979 CVX-16 Johnson 175
2002 Bennington 2275CC 90 Mercury
1985 Intimidator project
1989 Lowe 200 Redneck fishin Toon
2001 Godfrey Sweetwater pontoon 115 Rude

Offline carlsoncvx18

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Re: CVX 18 Prop
« Reply #30 on: June 09, 2019, 07:10:19 PM »
Try a laserII in a 21 pitch.  They are 13 3/4 dia. I run one on my cvx18
1987 CVX18.     1968 Glastron alpha sail boat
1977 GT150
1986 CV23
1984 Intimiadator
1981 CV27
1969 V-180 fundeck

Offline Hyperacme

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Re: CVX 18 Prop
« Reply #31 on: June 09, 2019, 07:17:38 PM »
1981 Mercury 228 spec. should be the same as a 1979 or 1980 228 MC.
If your using your speedo, might be off by a few MPH.

Offline Villager19

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Re: CVX 18 Prop
« Reply #32 on: June 11, 2019, 10:09:35 PM »
Thanks guys! Any recommendations on where to buy the laser II? Any good online stores etc?
Illinois Dave

1979 Glastron Carlson CVX-18
2014 Crownline 215 SS

Offline Hyperacme

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Re: CVX 18 Prop
« Reply #33 on: June 11, 2019, 11:22:09 PM »
You could also try a Quicksilver Lightspeed, same prop not as highly polished.
You can find Laser II's used on Craigslist or eBay for about $200 to $300.
New there about $500 to $600

Offline Villager19

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Re: CVX 18 Prop
« Reply #34 on: June 14, 2019, 08:38:52 AM »
Thanks Hyper!
Illinois Dave

1979 Glastron Carlson CVX-18
2014 Crownline 215 SS