Need Short Course in Lower Units

[velox]

I am probably one of the oldest guys visiting S&F, so my Mercury experience is out of date.
When I raced we had Standard lower units, Speedmasters and Sportmasters.
I now see Torquemasters, Fleetmasters CLE and others.
Will someone explain just what the lower unit designitions mean.
I am interested in the larger late models such as 225 Opti's

[StratosVT]

Ok, this is what I know or at least think I know:

CLE is an older (80's/early 90's) racing/sport type gearcase with low-water pickup holes on the bottom of the case. Some of them (ModVp case I think) have holes on the side instead of bottom. I think these were used on just 2.4 & 2.5 liter motors.

Sportmaster is the current production sport type gearcase with pointy nose & low water pickup. It replaced the CLE. These have heavy duty gears, etc. There are two versions (3.0 liter motor & 2.5 liter motor) and various gear ratios (1.62, 1.75, 1.87, 2).

Torquemaster has the same heavy duty internals as the sportmaster, but has a blunted nose and side water pickups. Designed for bassboats, etc. I believe these also come in a 3.0 & 2.5 version.

I think the fleetmaster is just a standard gearcase with standard size gears, etc.

All these gearcases are interchangeable as long as they are for the right motor/mid (3.0 or 2.5 liter).

[Techno]

I think fleet masters have the water intake up on the side.

Also at some year the shaft was beefed up to 1"? from the 7/8"? diameter so older props (standard) won't fit the newer shafts 'fat?'

[velox]

What lower unit would the new 225 Optimax use. A Fleetmaster or a Torquemaster.?

[Fish]

This is a great info site for lots of mercury stuff. If you scroll about 3/4 down the page there is info on the different cases.
http://www.biggerhammer.net/mercury/

BTW, you would be surprised at some of the ages on here... we have some guys that know how to prop a paddle wheel on here. :D :D LOL

[hydro-cat]

Check out this mercury spot. It explains the different types of G/C that they now produce and their applications for consumer motorer.

http://www.mercuryracing.com/products/consumeroutboards/gearcaseapplications.php

don't kowif I done this right or not.
But this will tell you about gearcases