915 is too short to use as a search term so i'll just ask...

What is the vehicle speed at redline in each gear for a 915 on a T4 with standard tires/wheels(205/50/15 or close). How much taller are the gears compared to a 901.

Is the shift pattern that of a typical 5 speed where 1st is top left? What are the key benefits of upgrading to the 915 on a near stock T4 2.0L. Thanks

People only upgrade to a 915 when they keep breaking their 901 boxes (big HP engines). The 915 conversion is not easy (a lot easier with the Wevo parts, but still) and certainly not cheap

So to answer your question, with a near stock T4 engine, it's a complete waste of money...

If you want a different gearing for your 914/901 box, do a search for "gear chart"
There's plenty of options

cheers,

Jeroen

Here is a site that shows the different gearing for the 901 and the 915. Benefits going to the 915 over a 901 with a 2.0L, damn, I can't think of any unless you are racing on a track where the stronger 915 is needed. For street none.
http://members.rennlist.com/chuxter/901&915ratios.htm

Geoff

The car i'm looking at buying already has a 915. I know its a waste of money to install without putting down a lot of extra power.

The benefits I'm thinking of might include: quicker shifts, less grinding, more accurate gates, taller gearing, higher top speed.

I think the better shifting part is only true if the conversion is done right.$$$ Better gearing for higher top speed? Hmmm, I think the 901 for the 4 has the tallest gearing and that you just run out of revs and hp at 6000 while a six can go to 7000 rpms. The six boxes are geared different so the engine revs higher to keep the fan speed up at crusing.
Hey, if the car you are looking at has the 915 great, its not a big plus without a hp six. Maybe a good car to convert! or sell the tranny out of.
Most 901 grind because people don't adjust the clutch enough and trash the syncho's plus they usually have 200k+ on them.
Geoff

It is commonly said that the 901 shifts better than the 915 when installed in a 911 (with equivalent shift linkage). The 901 has smaller, lighter parts, so there is less inertia for the syncros to overcome.

The two transmissions have the same (not great) syncro design, so there is no advantage there.