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mnpracing
07-19-2010, 07:55 PM
I have a question about prop rotation. Conventional wisdom says that a LH prop puts out a better surf wake on the port side. I've read this on many different sites. The Centurion Enzo has a feature called "Surf Right" that reverses the rotation of the prop to create a good goofy side wake, on the starboard side. I watched this video of Drew Danielo talking about boat set up and got confused. He says that a clockwise-rotating prop (which in my mind is Right hand rotation) puts out a better port-side wake. Am I understanding something incorrectly?

http://www.mmwatersports.com/drew_danielo_wakesurf_tips.htm

gcnettl
07-19-2010, 09:51 PM
I say the wake depends more on the balance(L-R) of the boat in the water. The deeper in the water one side of the boat is, the more washy the wake is on the opposite side. While cruising at wake speed, notice the prop wash behind the boat. It is straight out, with wake on both side.

Now the rotation of the prop will torque the hull a little bit. This will cause the hull to roll slightly depending on which way your prop turns.

The best way to counter it is to use weights to offset it. Ideally, you want your boat level (L-R) for the best formed wake on both sides.

cab13367
07-19-2010, 11:36 PM
The Centurion Enzo has a feature called "Surf Right" that reverses the rotation of the prop to create a good goofy side wake, on the starboard side.

Isn't that called "Reverse"?? And how do you surf while going in reverse?

mnpracing
07-20-2010, 01:00 AM
I didn't ask the question very well. It's common knowledge that with a left-rotating prop (as I have on my OBV), the wake is generally cleaner on the port side of the boat when surfing (all other things equal). Centurion has the Surf Right option where the shaft and prop rotate clockwise. The prop blades are angled the other way so that when rotating to the right, it still creates forward thrust. The props are not interchangeable with a LH transmission. Refer to the Acme prop list where it lists right hand and left hand props. Both create forward thrust when rotating in their respective directions.

The transmission is reversed so that it spins the opposite direction. The prop is also different in that the blades are tilted the opposite direction, thus creating forward force (just like the LH props) but by spinning clockwise, as viewed from the back of the boat looking forward.

What I was asking is that in the video, I think Drew Danielo is describing it incorrectly. He says that a clockwise rotating prop (with the Surf Right option) creates a better wake on the left side. I think he means the right (starboard) side.

sandm
07-20-2010, 08:07 AM
you are correct. but who surfs that side of the boat anyways :)

mnpracing
07-20-2010, 10:44 AM
sandm - unfortunately everyone in my family but me...

zegm
07-20-2010, 03:01 PM
Hummm......buy a backwards prop and an automotive starter???? :D


Years ago I decided to rebuild the good ole 351 Ford Truck engine that Master Craft put in their 1970's boat. I get the whole thing completed and am left to putting the ignition system back together. Wait little clarification here. ---When we tore the engine down well, it was a party with about 4 guys ripping things off the engine and throwing them in a box. A couple of week later the engine parts are back from the machine shop and we are going to rebuild here better than new. Everything is now put together with just the ignition left.
So now I am trying to determine the firing order of the engine so that I can install the plug wires on the distributor. Not knowing this I called a friend who works at a Tune Up Clinic. He gives me the firing order and the placement of the wires on the distributor cap. Now everything is done and we go to fire this bad boy up. Bang, bang, whosh bang!!!! Everytime we go to start it it is banging, backfiring out of the carb etc. For over an hour we try adjusting the timing, checking this checking that, nothing. Well it was time to stop and drink a beer and do some thinking different. All of a sudden I feel really stupid!!! I take the plug wires out of the cap and reroute them the opposite direction, instead of clockwise I route them counter clockwise. Hit the key and Hummmm the sweetest sounding a Ford 351 can sound! Moral of the story don't call an automotive guy about a marine engine. How would they know they rotate the opposite direction!!!