34 Sport Cruser prop size

[Capt.Erich]

I'm sorry to say that I have been off the reservation (forum) for a while. I'm happy to say that after two years of work I have my 34 Sport Cruiser in the water and starting sea trials after new power, electric, plumbing, steering, lighting, interior, etc., etc. etc...

Anyway, I've asked this question a while ago but cannot find the post doing a seach. What prop size are other owners of 34's using? I have a pair of 454 (350 hp) Crusaders. I've tried the four blade 21" wheels that came on the boat but they are obviously too much as I'm only able to get 3,500 rpms.

Thanks in advance.

 

[labrador]

Erich, where the hell have you been? Good to see you back!!!!
Skip

 

[34Hatt]

What reduction???

I have a friend with same motors in a 34C but we should check reduction!

 

[Capt.Erich]

Dan,

I'm 99% sure they are 1.9:1. The local prop guru is suggesting 19x19 for starters. I did eventually find the post I was asking a similar question a year or more ago. Several guys were saying the same thing. We are pulling the wheels tomorrow or Friday to see if these can be cut down or worthy of trade-in.

Skip! I've had an addition to my crew and my work has kept me busy traveling most of last year and I have wrapped up some big projects. I hope all is well in your neck of Trent Woods.

 

[BUSTER]

I replaced all the runing gear on a 34' trunk cabin a few years ago for a customer that wanted to get close enough to read what that white can with the orange stripe said. The boat had 454ci Crusaders and if I remember correctly the wheels were 20 X 20 4 blade and the gears were either 1:91 or 2:10,so your prop guy would be in the ballpark.

 

[34Hatt]

Eric I will try to call Bob tomorrow!

 

[dougl33]

When my Bertram had gas motors (Merc 454's with 1.9:1 BW), my props were 20x18 3 blade with a med cup. Cruise was 3100rpms at 18-19 knots and WOT was around 4100rpms and 28 knots. 19x19 4 blade may be OK. You should go over to boatdiesel. If you pay the $25 annual subscription you can use the prop calculator on the site. Its not perfect, but it will give you a good ballpark.