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View Full Version : "Torque Shift" props?



Tony
06-11-2002, 09:16 PM
What's the word on Torque Shift props (http://www.land-and-sea.com/public/articles/popular_mechanics/popular_mechanics_prop_article.htm) , sold by Land & Sea? Anybody ever try one?

MOP
06-11-2002, 10:08 PM
They do what they say but do not expect the top end preformance of a regular prop. If you are doing the run about type of boating you may very well like it, tough call!

MR MAGOO
06-12-2002, 06:30 AM
I bought one when they first came out. It was a very expensive doorstop! I found the blade design would not carry the bow when trimmed up.

Gary S.
06-12-2002, 07:37 AM
A friend of mine put a similar prop, Power Pitch Plus, on a 19' bayliner with a 4 cylinder, I am still impressed. His prop starts at 18 or 19 and I believe shifts to 22''. The boat now pulls a 250 lb skier out with no problems, and for what it is, has some impressive top end.

turbo2256
06-12-2002, 10:04 AM
I have one for sale a 25/32 not even used enough to finish breaking it in. Unbelieveable acceleration.

Ranman
06-12-2002, 10:49 AM
Hey Turbo, How much do you want for it? Any chance I can water test since we're in MI?

turbo2256
06-12-2002, 11:20 AM
Chances are if you are running a low power small block it wont have enough power to shift it. If I remember right it can go from a 9 to 18 pitch at low end to a 25 to 32 at top end so if you are running less than a 25 right now it wont do much good.

Rootsy
06-12-2002, 11:29 AM
I remember installing a few in the early 90's when mercury came out with their version. It had a series of springs, cams and weights and you could set the tension of them in the hub such that you could control the RPM at which it shifted which was trial and error based on torque through the prop. Mainly the prop was used on low powered or heavy boats to increase holeshot and planing capability and you sat it to shift just before you reached your cruising rpm so that you got the best fuel economy and speed. The prop was never meant to increase top end but to enhance low speed instead. I don't know how the blade design performed compared to other SS props... i do remember them being quite expensive.. somewhere in the 6 - 800 dollar range...

Ranman
06-12-2002, 12:15 PM
Turbo, Land and Sea's video shows it running on a Merc 350 260hp. I'm running a 350 MAG MPI at 300hp. Also, I currently turn a 25P Mirage Plus at just under 5000rpm so I would imagine it would be fine. I'd be curious to see how it handles though. I'd mainly use the prop for when I'm on the lake with the jet boats. They all hole shot me real bad, but I almost always end up passing them up on top. I wouldn't mind losing a mph or two on top if I could gain an impressive hole shot for when I'm playing with the squirt guys. Let me know cause I'd still be interested. Randy

Gary S.
06-13-2002, 07:02 AM
Tony, there is a discussion on the same prop on Hot Boat,,you may want to check it out before you buy from Land and Sea.

mikev
06-13-2002, 07:08 AM
here is a link to a SS version of this kind of prop its expensive though. http://www.aerostarmarine.com

MOP
06-13-2002, 07:20 AM
Hi grabed the URL for the forum on Hot Boat!

http://free.hotboat.net/ubb/Forum2/HTML/000225.html

turbo2256
06-13-2002, 07:33 AM
Ranman it would put the hole shot on alot of them

DonCig
07-30-2003, 10:05 PM
In the two years that have passed since the last post to this thread, has anybody tried the AeroStar prop. Expensive and well built with a range of 6" on the pitch change. I may be able to get then to discount to us, but I have never seen a post of this brand being used on a Donzi. I may be able to talk them out of a loaner since I have something that they want to buy from me.
www.aerostarmarine.com (http://www.aerostarmarine.com)

Don

Tomahawk
07-31-2003, 05:55 AM
I haven't run the Land and Sea but I have tested the Mercury and the Aero Star. Of the two, the Aero Star worked better. The Mercury was about $800 and did not shift consistantly. You have to futz with with them to try to get it to shift when you want it to. Sometimes it would hesitate before shifting and sometimes it wouldn't shift at all. Even when it did shift, a standard propeller would beat it in acceleration and top speed.
The Aero Star worked better and provided a terrific hole shot. Still some consistancy issues but pretty good. Again, not as fast on the top but I don't think that is the purpose of these things. Sort of neat to drive when it shifts and the engine tone changes. Reminded me of an old Chevy Powerglide. Aero Star quit making them at that time (couple years ago) but not sure their status now.

BillG
07-31-2003, 10:28 PM
Ranman
I don't think that prop or any other will let you leave like a jet drive. The engine in them goes to full RPM instantly and the boat catches up. All you will do is stress the drive and break something more than likely.
Bill G