Subaru 5 and new 6 speed cable shift info, The new 6 speed split case. Options

[914Subaru]

The Subaru 5 Speed split case transmission has been around for many years with the later ones have stronger 1st and 2nd gears. They are a linkage shift. I currently have the 5-speed in my 914 and it works flawless.

There are 2 types of Subaru 6 speed transmissions.
The Subaru WRX STI about 2004-? and have a one piece case. These are the biggest, strongest and longest transmission. Linkage shift. Arguably more than you need for most 914's because the extra weight and added rotating mass is not needed. Last I looked nobody makes the coupler to disable the AWD and needs to be welded as been shown on 914World.

The latest is 6-speed split case cable shift that is the same length as the 5-speed. In the US it comes in the the 2015-? WRX. (not WRX STI) also 2014-17 Forester and probably a couple others. There are different ratios between models but externally and fit appear to be the same. Outside the US they came in diesels also. Subarugears.com sells the coupler and rear cover. The only negative I noticed so far is it doesn't have a speed sensor.

I just purchased one out of a 2016 Forester with 43K miles. I will be using the shifter out of the Forester with custom length cables.
The Forester transmissions are selling for less than half the price of the WRX.

Here are some pictures comparing the 6-speed to an old 5-speed. I think this would be a good option to consider for future swaps.













To quickly identify the STI 6-speed I usually look for this divider plate the red arrow points to.

[Amenson]

From what I can find online the difference is the final drive.

WRX is 4.11
Forrester is 4.44

With the engine you are building Doug...you definitely don't want the 4.44.

[ahycaramba]

From what I can find online the difference is the final drive.

WRX is 4.11
Forrester is 4.44

With the engine you are building Doug...you definitely don't want the 4.44.

I'm really confused (IMG:style_emoticons/default/confused24.gif) I been using the calculator on subarugears website. According to my calculations on a 5 speed manual trans why would you want a final drive of 4.44 or 4.11 that tops out early at 113 mph or so in 5th gear @ 5000 rpm but when you have a final drive of 3.54 or 3.9 that will get you a top speed of around 130 mph at 5000 rpm.
Am I missing something? STI and WRX run F/D of 4.11 or 4.44 and cost much more than 3.54 or 3.90. Shifting points on a F/D 3.90 or 3.54 seem to be more desirable than the 4.11 or 4.44.
am I wrong and would I be losing power / torque due to taller gears?