Prop recomendation help please

[jdblya]

Hello all,

I have a 1995 195 Four Winns Sundown cuddy. It is powered by a Volvo-Penta SX Cobra 5.0fi (ford 302 efi). Currently I have a Michigan Ballistic 21p prop. I thought that I like this prop at first, but watching it spin in the driveway, it just looks out of round and unbalance, and it has a couple dings in it and I want to purchase a new prop, but want something with a hub system, and not another Michigan prop. I was looking at three props, and any advice or info would be good. I have tried both a 19p and a 23p prop in the past and seem like the 19p had some good hole shot, but the engine reved to high. The 23 felt slow out of the hole, and seemed that the rpm was down. The 21 feels really good overall to me, however I believe that the RPM of my engine is supposed to be something 4600rpm but according to my tach (don't know how accurate) I run around 5200 rpm and the engine feels fine, with plenty of power. I'm not really sure why they suggest 4600, seems pretty low considering the cam selection and the engine. But any way, here is what I am looking at.....

Stiletto Advantage II
Solas HR Titan 3
Quicksilver Lightspeed

I generally use the boat for tubing, and cruising around, so I the best compromise of hole shot and top speed.

Again, thank you in advance

John

 

[cr2k]

Re: Prop recomendation help please

How about a 21p compromise?

 

[Bondo]

Re: Prop recomendation help please

I run around 5200 rpm and the engine feels fine, with plenty of power.

Ayuh,... A 302 won't live very long at 5200rpms...

 

[jdblya]

Re: Prop recomendation help please

It still still pulls fine and has power at 5200. It does not run out of cam. Like I said, with the 23 pitch prop, the boat felt sluggish and felt like it the engine would stop turning it before it high its max hp.

 

[Tail_Gunner]

Re: Prop recomendation help please

It still still pulls fine and has power at 5200. It does not run out of cam. Like I said, with the 23 pitch prop, the boat felt sluggish and felt like it the engine would stop turning it before it high its max hp.

Unless they have rebuilt the valve train 5200 will smite a 302...if it pulls hard as you say your way under propped..You need to find a pitch where it stall's at 4600..that is it runs out of steam..

21@5200
22@5000
23@4800
24@4600

You need to check your tach for proper calibration..While not impossible a 24p on a 302 is way out of the norm..

 

[jdblya]

Re: Prop recomendation help please

Unless they have rebuilt the valve train 5200 will smite a 302...if it pulls hard as you say your way under propped..You need to find a pitch where it stall's at 4600..that is it runs out of steam..

21@5200
22@5000
23@4800
24@4600

You need to check your tach for proper calibration..While not impossible a 24p on a 302 is way out of the norm..

The valve train is stock. At one point I had 1.6 roller rockers on it, but it is back to stock again. I am not 100% confident in the tach. My Four Winns has one of those all in one clusters, like on a car dash. I don't have separate autometer or feria style gauges. I may hook up a normal autometer tach just to see what is going on. As far as the 24p prop, I know what you are saying. Seems way off. Like I said, the 23p Ballistic prop I tried out just did not seem to run as well as the 21p. I don't know if it is the Ballistic design or not, but it just felt sluggish out of the hole. I think that a 22p might be right on, but there are very few options when it comes to a 22p. The marina told me that the Stiletto props run a little more pitch than advertised. For example. a 19 Stiletto runs more like a 21 oem style prop, and a 21 runs more like a 23, etc. I don't know if there is any truth to that or not.

on a side note, I went and dug up the original volvo aluminum prop that came with the boat, and it is a 14-1/4 x 21

 

[Tail_Gunner]

Re: Prop recomendation help please

Stilletto's do have agressive cupping..but a 20ss is more like a 21 ss without cupping..

http://boatpropellers.iboats.com/Vo.../9109/?**********=545026134&*******=690732172

There's a nice prop..again i will advocate a 4 blade ss..20p 4blade stilletto bay pro 11 would be intresting...