79 CVX16SS Best Prop Size?

[demian5]

I searched and didn't really find anything solid.

What would be the factory prop size on my mercruiser 140 (3.0)?

What would be a good river cruising, decent speed, no pulling stuff, prop size for it?

right now it has a large prop, I think 21", unknown pitch, but I can tell you it gets up on plane fast, but only goes about 35 (GPS) at 4300 RPM.

Thanks!

Motor is fresh and im putting it back together for this season.

[75starflight]

4300 is on the low range of that engine's wot rpm. I am running a 21 pitch laser 2 on my v-179 starflite with a mercruiser 140 at wot I will run around 4500 rpm and my top speed is around 50 mph via gps. 

Your best bet is to test props and find one you like for what you want to do.

[demian5]

Thanks. My issue is the old motor broke off an exhaust valve while cruising at 4300 so thats all it had. I had to get a new motor.

[demian5]

Thanks. My issue is the old motor broke off an exhaust valve while cruising at 4300 so thats all it had. I had to get a new motor.

What diameter are you running?

[Hyperacme]

1977 & 1978 Glastron P.I.G.'s list "15 x 23P cup".
Nothing for prop pitch listed for 1979 CVX's and latter Metric's.

[Plugcheck]

I had a 15- 23p, too big.  Tried a 15-19p, too small. Had a 14 3/4"-21 just right.  51-52 mph at 4800 rpm.

[Hyperacme]

Interesting .. Brandon's V-179 is listed with same prop.
His boat is about 225 lbs. heavier.
YEP .. All about testing … testing & more testing !

[75starflight]

Interesting .. Brandon's V-179 is listed with same prop.
His boat is about 225 lbs. heavier.
YEP .. All about testing … testing & more testing !

I would love to put a 23p laser 2 on my 179. I have been looking just going too high at the moment to justify it.

[Hyperacme]

I would like to have a shop add a little more pitch to my 22P Laser II, I can get a little more then my red line on a good day.
But .. the expenses of doing it and not working so I have to go back wouldn't be worth the small amount I'd gain.
Maybe .. Maybe not …
 

[Jason]

23p Laser II would work perfect on a CVX16SS. Excellent top end, holds well in corners, good take off. A V179 has too much hull in the water for it to work well on it but the CV's, CVX's do not.

Best prop I have found so far for my CV16SS 140.

View my results here:
http://forum.cgoamn.com/index.php?topic=806.msg7016#msg7016

[Plugcheck]

Considerable difference between a CVX and 179 tri-hull.  Not a fair comparison if only looking at props.  The 23 that cames on mine was not a modern prop, more of a mouse ear.   I ended up using an aluminum prop that gave decent results.  It was a great boat, but if you're performance oriented, the four cylinder will only go so fast.

[demian5]

So I was "given" a Stainless Quicksilver 48 16548 A40 23P Laser II. It appears to be a 13 3/4" diameter 23P prop.
I know the OE calls for a 15" 23P. Will the smaller diameter cause issues or be better than my 17" 19P aluminum I have (this new prop is much heavier)?

Thanks!

[demian5]

Here is what I got

[Hyperacme]

Prop mfg. determine what diameter works best with a certain pitch, so you can't really choose what diameter you want.
Prop info in P.I.G.'s are 40 years old and technology has changed and improved, guessing the P.I.G. info is for aluminum prop ..

They are heavier .. but are also stronger and don't flex at higher speeds.
If some one gave it to you .. that's a great deal. There worth $200 to $300.
Try it !    See if it works .. If not you could have a shop pound it down to a 22P or sell it on CL or eBay and try a 21P Laser II.
 

[demian5]

Prop mfg. determine what diameter works best with a certain pitch, so you can't really choose what diameter you want.
Prop info in P.I.G.'s are 40 years old and technology has changed and improved, guessing the P.I.G. info is for aluminum prop ..

They are heavier .. but are also stronger and don't flex at higher speeds.
If some one gave it to you .. that's a great deal. There worth $200 to $300.
Try it !    See if it works .. If not you could have a shop pound it down to a 22P or sell it on CL or eBay and try a 21P Laser II.
 

I actually got 2 props given to me. but this seems to be the pitch that matches what they spec out for the boat for best performance. Thanks for the feedback, it wont cause damage to be drive vs the aluminum will it?

[Hyperacme]

Nope .. Won't hurt LU .. Unless ya hit something .. LOL
That's a older style Laser II with square vent holes and guessing not a Flo-Torq hub.

We are all just guessing about a starting point for your set up.
Shoot for your max rpm's and adjust pitch from there.

Mercury PVS ..
https://samerwebapp01apncus01.azureedge.net/mmgw-env-b/filer_public/81/a4/81a4aef2-f0f5-4604-a183-d5d2cec22ea8/performance_vent_system.pdf

Info on what a Flo-Torq is ..
https://samerwebapp01apncus01.azureedge.net/mmgw-env-b/filer_public/75/59/75591e9a-8637-4e33-97b1-8a9d44b2151b/flo-torq_propeller_installation.pdf

[demian5]

The aluminum prop that came with the boat has a hub that's 4 sided and come out. No, this prop has a rubber surrounding the hub but its permanent. What I hit where i go is possibly sand bars...

[Jason]

Great deal! I think you'll be happy with it. You will need to modify, remove, or replace the trim tab. I believe an offset trim tab is available but I just cut a notch in mine to clear the prop.

[demian5]

Great deal! I think you'll be happy with it. You will need to modify, remove, or replace the trim tab. I believe an offset trim tab is available but I just cut a notch in mine to clear the prop.

For the 13 3/4 I wont need to modify the trim tab. the larger prop cleared as well. I will need to dial it i cause the boat pulled to the left bad.

[Hyperacme]

Do you have power steering ?