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Rayhill
10-12-2002, 05:55 AM
The previous owner of my boat changed the gearing in the Alpha from 1.5:1 to 1.3:1 to handle the added power from the twin turbos. It shifts back into neutral hard from revese or forward gear. He said the hard shifting is due to the gear change. Is this true? How can I change it?
Thanks
KB

Tinkerer
10-12-2002, 05:08 PM
Sounds like the engine interupter switch is not set properly.

Infomaniac
10-13-2002, 05:48 PM
Tinkerboater:
Sounds like the engine interupter switch is not set properly.I agree. The ignition interrupter helps it get out of gear. Torque holds it in gear. It is worse with a taller gear. The cable will eventually stretch unless you get it fixed.

Rayhill
10-14-2002, 02:22 AM
Aha!!! wink
I have monkeyed around with that.
I guess the sweet spot is harder to find with the taller gear!
I will replace the cable and try again when I get my motor back. Fried a piston with a twin turbo set up! :mad:
Thanks
KB

Tinkerer
10-14-2002, 06:45 PM
With the alpha drive the gear ratio or prop pitch shouldnt mater since the interrupter switch should kill the motor for a split second and that is all it takes to get it out of gear. If it doesn't come out of gear with a properly adjusted switch the engine will kill completely. (Many years with a high HP engine in front of an ALPHA SS)

Infomaniac
10-14-2002, 07:29 PM
Tinkerboater:
With the alpha drive the gear ratio or prop pitch shouldnt mater since the interrupter switch should kill the motor for a split second and that is all it takes to get it out of gear. If it doesn't come out of gear with a properly adjusted switch the engine will kill completely. (Many years with a high HP engine in front of an ALPHA SS)It damn sure does matter if the interrupter is not working. My Alpha SS had 1.3 gears and a 27 pitch prop. It was hard as hell to get out of gear when the interrupter did not work. If it had a 2:1 gear and 19 prop it would not be nearly as hard to get out of gear.
If his was not working properly, changing the gear made it worse. :D
Torque holds them in gear. That is why you need to interrupt the engine so you can pull it out of gear. More prop or gear ratio = more torque holding it in gear.
[ October 14, 2002, 08:31 PM: Message edited by: Infomaniac ]

Rayhill
10-15-2002, 01:18 AM
Educate me? Havent heard of an Alpha SS. Is it the big block Alpha? Would the interupter switch and linkage setup be different than the standard Alpha?
Its a slow process, but I am having a aluminum headed monster bitch motor being built for my twin turbos. I cant ignore my outdrive. Its a standard Alpha with 1.3 gears, gear oil temp. gauge, and nose cone. Thats all I know about it?

Tinkerer
10-15-2002, 06:51 PM
INFO-- Isn't that what I said. With a properly operating interrupt switch the gear ratio or prop pitch doesn't mater. If the switch does it's job the drive should slide out of gear easily. If the drive doesn't come out of gear and pressure is kept on the shifter the engine will kill completly.
RAYHILL-- the alpha SS is just a short shaft version of the alpha drive. It is 2 1/2 inches shorter then a stock alpha. The alpha in any version wont handle much more than 400 HP. I had a little over 500 HP coming out of a SBF (BOSS 302) and it was WAY TOO MUCH HP for the drive.
[ October 15, 2002, 07:57 PM: Message edited by: Tinkerboater ]