prop Rotation

daleo · 02-23-2010, 12:48 AM

asuming that Bravo 1x drives will run either direction
on a 2007 28 heat does it perform better with a left hand or right hand prop and why

CB-BLR · 02-23-2010, 01:06 AM

It runs considerably better with the standard (right spinning) props. I have tried spinning the props in both directions on a Heat.

I don't know the physics behind why this is.... it just is.

Chris

Steve Zuckerman · 02-23-2010, 08:27 PM

The helm is on the right to counter balance right hand prop torque in 90% of the recreational boats made. If you ran left hand rotation (particularly running by yourself) the boat would lean seriously to the right (starboard) under power, negatively affecting handling.
Exceptions to the starboard helm rule are center cockpit race boats (F1s and drag boats/circle and drag hydros), center console offshore fishing boats, and offshore cats. With the exception of F1 race tunnels and hydros, the others generally have multi engine and drive setups that cancel propeller torque through counter rotation, making them less sensitive to helm placement.
The Heat will still torque roll to the left even with the helm on the right. I try to eliminate it by running approximately 1/4 tank more gas in the starboard tank. You can tab it out, but that usually slows the boat somewhat.
Regards,
Steve

bullittcustoms · 02-28-2010, 06:18 PM

DAMN IT!! I just bought a LH 27 P5-X for my boat. I asked 3 people if it would matter and they all said it wouldn't. That's great!! LOL He told me I could trade it if I didn't like it. I really wanted a B1 28.

Derek

Steve Zuckerman · 02-28-2010, 09:43 PM

Quote:

Originally Posted by bullittcustoms

DAMN IT!! I just bought a LH 27 P5-X for my boat. I asked 3 people if it would matter and they all said it wouldn't. That's great!! LOL He told me I could trade it if I didn't like it. I really wanted a B1 28.

Derek

Derek,
You can try it before you let it go, but I think you'll find it to be a pain in the azz. The 5 blades are great props, but because they lock up better than four blades, they generate even more rotational torque. I think you'll be running way low to starboard. You will have to run a lot of weight to port (or starboard/right down tab) to offset the propeller torque.
I have a friend who was running a 30" B1 on a Baja 272 with a built motor. We had planned to let him try my TU blueprinted 30" B1, when I noticed he had been running a left hand 30". I asked him if it was running low to starboard and he said "yeah, but I've learned to drive through it"............
I said "I think you'll like this one a lot better". He picked up 5 MPH and his boat handles a lot better.
Regards,
Steve

bullittcustoms · 02-28-2010, 10:05 PM

Is it OK to try the prop and throw the boat in reverse before switching the linkage? I aready have it, might as well try. Right?

Thanks, Derek

Steve Zuckerman · 03-01-2010, 11:28 AM

Quote:

Originally Posted by bullittcustoms

Is it OK to try the prop and throw the boat in reverse before switching the linkage? I aready have it, might as well try. Right?

Thanks, Derek

Yes and yes. It will be an interesting experiment (sounds like Chris has already tried it). I never have.
Let us know how it goes.
Regards,
Steve

bullittcustoms · 03-01-2010, 02:40 PM

Quote:

Originally Posted by Steve Zuckerman

Yes and yes. It will be an interesting experiment (sounds like Chris has already tried it). I never have.
Let us know how it goes.
Regards,
Steve

I let my wife pick up the prop. I just pulled it our of the backseat and it is a P5 ...... not a P5X

How screwed am I now? Is it even worth testing? Thanks for the help.

Derek

CB-BLR · 03-01-2010, 11:23 PM

I have never tried a P5....
I have tried a P4, and it was pretty fast... I just could not get it to hook up on the bottom end.
Labbed bravo's worked better overall.
The P5 should be an interesting test... though the left hand thing most probably wont work so well.

I have tried three different left had props.. a bravo, a P5x, and a Hering.

When trying left handed props, I borrowed matching sets of counter-rotating props intended for twin engined boats.
They all made the boat handle much more poorly than their right handed counterparts.

Chris

Steve Zuckerman · 03-02-2010, 12:09 AM

Derek,
I believe the P5 is a stern lifter designed primarily for light race boats. A lot of the Vee Light boats (27' to 30' canopied vees, like Phantoms with 525s) run them.
These boats, having no cabin amenities, are light enough in the nose to get away with this prop. We need bow lift.
Oh well, you have it. May as well try it. I don't think it's going to make you or your boat happy though.
Regards,
Steve