Perplexed on prop choice

[JeffT]

I had a 14.5 x 17 3 blade on a volvo sx 5.7 I/O getting a max 5200 wot hole shot ok not great on alum blade (kind of chewed up). We mostly do wakeboarding so the hole shot is important and high end speed is not so much. Was told to go with a 4 blade...the mechanic said go with a 16" and the dealer said go with an 18"...got the 18" but does not give me a hole shot if someone is sitting on the back jump seats...but if everyone stands to the front of the boat get better hole shot....do I stay with an 18" or would I get better results with a 16". Or am I better off sticking with a 3 blade 17"?
Thanks for any input

 

[rrhodes]

Re: Perplexed on prop choice

Dropping pitch increases Holeshot and decreases top end speed. What is your Max recommended RPM for your motor?

Each inch in pitch you drop will increase your WOT rpm by about 200rpm

 

[crxess]

Re: Perplexed on prop choice

Have you tried re-trimming first to reduce/eliminate transom squat? The less the tail digs in the quicker you hole shot will be and the less you will need to sacrifice top end.

What type boat is this?

 

[steelespike]

Re: Perplexed on prop choice

Please give us the info on the hole package;with details not just the boat model.

 

[JeffT]

Re: Perplexed on prop choice

I have a 1994 Wellcraft 220 Eclipse with a sx Volo penta 270hp. I was getting wot 5200 53 mph on a 14.5 x 17 3 blade but the hole shot was about 8 seconds to plane. Now I get 10 seconds hole shot, 4400 rpms at 39 mph wot on a 18" 4 blade alum. I was told that if I went to a 16" my rpms would increase, my top end may increase but my hole shot would be slower.
I don't have trim but use my drive by lowering and highering it.

Any suggestions?
Thanks

 

[steelespike]

Re: Perplexed on prop choice

A 4 blade will usually improve hole shot at a slight sacrifice of top end.
Usually when you go to a 4 blade you would drop about 1" in pitch to make up for the extra resistance of 4 blades.
Dropping in pitch will improve hole shot with any prop,all things being equal.If you read the prop helps on the iboats prop store page you will understand props a little better.
Of course we'er here to help get it right.

 

[MikDee]

Re: Perplexed on prop choice

It sounds like you're overpropped, go with the 16" 4 blade.