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Pman
04-23-2003, 03:39 PM
I have a 2001 Outback with the stock 310 HP motor. I put an OJ 13X13 4-blade prop on in place of the stock 3-blade. I've been told by other boat owners that you calibrate the speedos by cruising with the motor at 3000 rpm. This speed should be 30 mph and to adjust the speedos accordingly. Is this true? Thanks.

MartyC
04-23-2003, 06:27 PM
Let me know how you like that prop. Thinking about going to a 4-blade.

Brian Raymond
04-23-2003, 11:33 PM
Pman, I feel you will be happy w/your new 4bl. You should notice a quicker hole shot, which the skiers and footers will enjoy, and be able to hold your speeds much better. For the boarder, it is nice because it lifts the aft end up and forces the bow down at lower speeds to get more boat in the water for a bigger wake, and not have a bow high take-off, even when loaded. Todays high h.p. and torquey motors engineered by Indmar, have changed the rule of thumb a bit on the 4bl. Set your speedo at 36mph@3800r.p.m., this will get you darn close to the high $ G.P.S. Brian Raymond

Brian Raymond
04-23-2003, 11:34 PM
Pman, I feel you will be happy w/your new 4bl. You should notice a quicker hole shot, which the skiers and footers will enjoy, and be able to hold your speeds much better. For the boarder, it is nice because it lifts the aft end up and forces the bow down at lower speeds to get more boat in the water for a bigger wake, and not have a bow high take-off, even when loaded. Todays high h.p. and torquey motors engineered by Indmar, have changed the rule of thumb a bit on the 4bl. Set your speedo at 36mph@3800r.p.m., this will get you darn close to the high $ G.P.S. Brian Raymond

Pman
04-24-2003, 04:36 PM
Brian, thanks for the speedo calibration. And yes, the 4 blade makes a difference out of the hole and maintaining speed. The first season I owned the boat it was with a 3 blade. I purchased an OJ force 4 blade mid-next season and definitely saw a difference. At the time, stainless 4 blades weren't out (by OJ), but would like to try one someday.

TheBeeZ
04-24-2003, 05:18 PM
If you can borrow a GPS from someone this is a very easy and very accurate way to calibrate your speedo. You can also check it at any speed.