Just spent awhile trying to come up with good pics of the 915 case modifications. Couldn't find any at all. I'll post mine once it's done, but if anyone else has them, post 'em here please.

Mark, I hunted for pictures of mine and I had lots but not many of modifications. Here is what I have....

Case mod:
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You don't need a heavy side cover since the load is now on the case side so I inserted a sleeve for the magnetic speedo pickup in the stock cover
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I also modified the tail housing of a WEVO side shifter to accommodate the very large 5th gear (for cruising). They said it wouldn't fit but my grinder said otherwise..ha ha
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The case mod is easy and exactly like the posted photos. Basicly clearancing for bolt head room. The hall sensor is also straight forward no more difficult than making a hole in the correct location or pressing in a bushing.

I paid to have mine done. Then watched a friend with his and that "fuh I paid someone to do that" head demon came to life. It took my buddy about 20 minutes to remove some material from the case and another 30 minutes to install a hall sensor. A spark plug wire retainer made a perfect retainer for the hall.

In the end with all the internal work, new bearings, retainer plate and dogs it was a fair price but the clearancing charge was only 1 hour bench time which equates to " it aint hard when its all apart".

Dont forget to turn the vent on top 180 degree's or else you will have a 915 fountain.

Jeff just reminded me.....You have to machine some material off the ring bolt heads. If I recall there is a groove in the bolts for a retainer and I cut off everything from the groove up and discarded the retainers in favor of loctite. The heads are then very small but they can still be properly torqued.

I'm old and had too much head injury to retain more than that....

OK, I found a few more

Here is how I machined the bolt heads
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Light weight gears really help shifting the balky 915
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Size comparison of a WEVO equipped 915 vs. a stock 914
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Great stuff Paul!

I like the way you think. . .

BTW, The lightened gear set is awesome!!

Thanks. I think that has a lot to do with how nice my tranny shifts. There is much less mass for the cheezy Porsche syncros to have to slow down, especially for the notorious 2nd balk. (mine doesn't balk)

I also have a special clutch disk with a one sided marcel spring that also really helps. The disk doesn't have to slide on the splines when I shift. The two combined makes it shift like a real tranny...ha ha

And finally (waiting for the bashing) I use Mobil 1 (I don't race it)

I was always taken aback by how much people will charge for the ring flip. Stupid easy and not labor intense. Thanks for the posts. I, of course, love this stuff.

Hey! I want lightened gears!!!

Yeah, that's cool!

Paul,
IIRC you have a special 1st and 5th gear? 1st gives you like 60 mph and 5th that allows you a 3000 rpm highway cruise? What are the sources for them? Which gears did you lighten?

Yes, my first second and fifth are custom. 1 and 2 are lightened since they are the balky culprits and large in mass

My fifth is a gear set out of a 7:31 915 installed in my 8:31. Very tall for cruising/mileage and low noise. As you know you don't have to yell at freeway speeds in my car as it lopes along at 26-2700 at 70 mph. 1-4 is close for ass-kicking!

My first gear is something you would not want for a commuter...too tall for idling along

I frequently downshift my car into first at well over 30 mph (no kidding) and you can't have the balk if you want to do that. But the 1-2 gear area is where my car shines since it's up to 80mph (Rob you remember)

Don't forget the TB Dif to get it to the ground

Here is my gear chart
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Oh I remember! I kept thinking 'I would have shifted three times by now!'

Thanks for the information Paul!