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Posted by: jimkelly Mar 26 2011, 06:45 PM

http://www.cableshift.com/930/930%20page.html

http://www.californiamotorsports.net/930.htm

http://forums.pelicanparts.com/porsche-914-914-6-technical-forum/428805-914-conversion-930-turbo-engine-trans.html

http://www.gt40s.com/forum/gt40-build-logs/16138-kiwi-scratchbuilt-15.html

http://www.pbase.com/9146gt/930_turbo_racing_gearbox

http://www.negativereinforcementracing.com/week23.htm

Posted by: kg6dxn Mar 26 2011, 07:47 PM

I don't think you can flop the ring/pinion so you have to flip the tranny. You also need to deal with upsidedown lubrication. I would go with http://www.cableshift.com It looks like a good system and the price is resonable. Or fab your own system...

Posted by: jmmotorsports Mar 26 2011, 08:06 PM

California Motorsports can flip the 930 ring gear. G50 can't be flipped.

Jerry

Posted by: Dave_Darling Mar 26 2011, 11:02 PM

I believe the housing has to be machined in order to flip the R&P. Oiling setup needs to be changed if you flip the whole box. Either can work; and it should survive a good amount of torque.

--DD

Posted by: John Mar 27 2011, 09:07 AM

The case does need to be "clearanced" for the ring gear.

Vellios used to have the parts to convert to a side shifter for 930 transmissions. I would assume that they are all long gone now, but it is possible to flip the ring gear without too much hassle.

It's similar to the clearancing required in a 915 box.

Posted by: pcar916 Mar 27 2011, 09:19 AM

Inverting the 930 is easy to do, it was made with that in mind. But the CV deflection angle will be pretty steep unless your car is lowered a lot because the output flanges will be considerably higher. I don't know what the angle will be (forgot) but you should measure and see if you'll need the larger angle the 108mm 930 cv's will give you. Without going out to the shop to measure the flanges will be about 4in higher in the car than before.

Someone else may have made a calculation on the horsepower loss developed by the new larger angle as well but I haven't done it.

Good luck

Posted by: jimkelly Mar 27 2011, 09:36 AM

at $59.00 each for 108mm cvs - plus, axles, axle flanges, and wheel hubs - seems like cheap insurance - if anyone can figure out what all the pns are?

http://www.dunebuggy.com/shop/index.mp?szAction=viewItem&iItemID=854

http://forums.pelicanparts.com/porsche-911-technical-forum/191039-cant-find-flanges-930-trans-accept-lobro-934-cvs.html

http://www.performanceforum.com/wesvann/914a/know-cv-axle/know-cv-axle.htmlhttp://www.performanceforum.com/wesvann/914a/know-cv-axle/know-cv-axle.html

Posted by: pcar916 Mar 27 2011, 10:41 AM

I know where 108mm (course-splined turbo flanges) flanges are, and even some 914-6 axles you can modify to fit those CV's. But SwayAway (or equivalent) axles that free-float and self-center may be best. I've been running 108's on my car for years until I went to 944 cv's and stock -4 axles. There is significantly less weight on the 100mm bits and axles... like 3-4 pounds lighter than the 108's.

The pn on my turbo flanges best I can read them is 915.(382 or 882).209.01 and you can use SC stub axles without any modifications or 944 stubs with a spacer.

Between the vented rotors and the bigger CV's etc, to keep the weight down at the rear wheel I'd always run aluminum calipers rather than steel.

Almost forgot... Here's a site with some cable shifter solutions for our transaxles (and some others). I haven't used these guys personally.

http://www.cableshift.com/930/930%20page.html

Posted by: Dr Evil Mar 27 2011, 06:20 PM

Yes, you can flip the diff in a 930, changing the oiling is not hard either, but does take some massaging. I have a 930 box apart if you want pics. I would love to build it and sell it to someone

I would even sell it as is as I am not intending on using it. I want a 915 (which is basically the same box, but in a 5 speed configuration).

Posted by: jaminM3 Mar 27 2011, 10:19 PM

Factory Five does a their GTM Super car using Corvette parts and a G50 transaxle from Porsche. They must be running it upside down or flipping the ring to make it mid-engine...

...right?

Posted by: jimkelly Mar 28 2011, 04:27 AM

info i have seen says the g50 much be installed upside down ( inverted ) for mid engine use.

http://www.kitcentral.com/index.php?name=PNphpBB2&file=viewtopic&t=4605

but i have also read that the g50 stock gear ratio's are not ideal for a v8 but that it has modern syncros - but the g50 is more costly than a 930.

Posted by: pcar916 Mar 28 2011, 11:36 AM

Yeah, and the G-50 is a whopper... way heavier than a 930 or a 915. Shifts like butter though. Even better than a 914 transaxle. Which we all know is unsurpassed.

Posted by: jimkelly Mar 28 2011, 11:49 AM

g50 shifts better than a 901 - that is a plus

but i hear 930 - not better than 901 - assuming linkage on both is decent

Posted by: jimkelly Mar 28 2011, 11:51 AM

pics please doc

what year 930?



jim

--

Attached thumbnail(s)

Posted by: pcar916 Mar 28 2011, 04:15 PM

The 930 and the 915 ar very similar (as the Doc has said) and they shift similarly because they both have approximately the same inertial loads and they have the same synchronizers as the 901/914 boxes. The 930 doesn't have the extra mass that the 915 has in the fifth gear, but it has thicker gears. Hope that wasn't too geeky. I've never weighed the gear clusters to compare them... Doc?

Anyway, you can't approach the G-50 for shifting smoothness, but the 930/915 boxes shift great if they're well set up and as you've stated, the linkage is well executed and adjusted properly.

Noodling this is fun eh?

Posted by: jimkelly Mar 28 2011, 05:26 PM

another wrinkle in installing a 930 trans is whether or not the clutch can be ativated by cable or whether a custom hyraulic set up needs to fabricated?

http://www.914world.com/bbs2/index.php?showtopic=90342&mode=threaded

Posted by: pcar916 Mar 28 2011, 05:57 PM

Not a deal breaker. I like the both for different reasons. Hydraulic is great once it's installed and bled. But it takes more maintenance with the bleeding discipline. Cables are simpler but need adjustment now and then. What's your preference?

In the hydraulic systems as long as you don't integrate the clutch system into the brake system (via a shared fluid reservoir) you're good! Making them share a master-reservoir is a maintenance nightmare.

Posted by: Britain Smith Jul 1 2013, 11:04 AM

I know this is an older thread...however several trans specialist seemed to be in here.

I need to find a picture of the back side of a 930 ring gear that has been machined for clearance in a flipped configuration. If not a picture, some information on how much material to remove.

I have a 930 case that has been machined for a flipped ring gear, however I don't have the ring gear itself.

Anyone?

Thanks in advance,
-Britain