tripomatic trans

[effvee]

Hello, has anyone attempted or installed a Prosche tripomatic in a 1303 before? Also I'm told there is a later version of automatic trans for the Porsche, has anyone installed one in a bug yet?
Does anyone know of its total length verses a 915 manual trans?
At this point a have a new ABT diff carrier and that was before the 915 came to me as a better way to go, so now I'd like a five speed such as the 915 instead of building up a five speed from a Berg adapter, nothing bad to say about it just feel the Porsche will offer better freeway flyer gears from the start.

[Michael Ghia]

The Tiptronic gearboxes built by Porsche started off in the G50 series and then have moved into the latest 996 and Boxsters. The G50 is a lot bigger than a 915, longer and heavier. These G50 boxes were what was used in the 993's.

The 996 and Boxster Tiptronics are pretty useless to us as the engine to gearbox mounting pattern has changed away from the standard 4 bolt so you can't bolt anything too it apart from a 996 or Boxster engine.
Also, Porsche are not yet selling parts to rebuild the 996 or Boxster gearboxes, you have to buy a new one instead!!!! Incidentaly, the 996 and Boxster S gearboxes are very different. Porsche did not use the same case and simply "flip the diff" as they did in the 914.

MG

[Shad Laws]

Hello-


Hell, has anyone attempted or installed a Prosche tripomatic in a 1303 before?

I think you are confusing two different transmissions... a Sportomatic and a Tiptronic.

The Sportomatic is the Porsche equivalent of VW's Autostick. They both began production in 1968, following the 1967 VWAG aquisition of NSU (who developed the idea in the first place :-). The gearboxes themselves are manual transmission gearboxes. However, instead of simply having one manually-operated clutch to connect the engine to the gearbox, there is both an automatically-operated clutch and a hydraulic torque converter. To the driver, the car is just like an automatic transmission that you have to shift yourself. To purists, both the Autostick and Sportomatic are hated furiously. But, they really aren't that bad of devices... 99% of the horror stories you hear are because people don't understand how to work on them, so they are often in disrepair :-).

The Sportomatic is similar in size to a 901 gearbox. The early 905 boxes had 4 speeds, but weren't too strong. Then they went to a 925 gearbox that, although it was still based on the 901 gearbox and had 4 speeds, was stronger. The last revision of the 925 gearbox only had 3 speeds, but was the strongest of all. I don't know of anyone who has put one of these into a VW, but have often thought that it'd be a novel idea :-).

The Tiptronic is an electronically-controlled automatic transmission. Whereas the Sportomatic is more like a manual tranmission modified to be clutched automatically, the Tiptronic is definately an automatic transmission modified so it can be shifted manually if desired. They are significantly bigger than even a G50 transmission. In fact, to get the package to fit, they had to do something very funny with the differential.... know how most VW/Porsche transaxles have the diff right in line with the gearbox and engine? Well, that didn't fit. The engine goes straight to the gearbox. At the forward-end of the gearbox, there is a longitudinal output shaft that runs outside and to the right of the gearbox back to where the diff "should be," and the differential is outrigged on the right-hand side of the gearbox. So, it is quite bulky and wide, and heavy, and requires a computer, and is expensive.

There's an article in both Excellence and HotVWs about a bus with a Tiptronic in it, but they also have the 6-cylinder 911 engine in there and all the ECU stuff, so it's probably quite a bit more straightforward than having the gearbox alone.

Take care,

[Shad Laws]

Here's what a 5-speed 993 Tiptronic looks like. Note the outrigged diff... odd, eh?

Take care,

[effvee]

Hi guys, I meant 'hello' not hell. I sure wanted to try the automatic sence, but such is life. Shad big thank for the pictue of the transmission.

[effvee]

Hello, can anyone tell me the length of a tiptronic that shat showed a picture of? Also are they a strong transmission. What are there prices?

Thanks

[Shad Laws]

Hello-

Hello, can anyone tell me the length of a tiptronic that shat showed a picture of? Also are they a strong transmission. What are there prices?

You e-mailed me about this when I was out of town, and I replied yesterday, but the e-mail bounced back :-(. Anyway, here's what I said:

I don't know its size offhand. However, remember that it was produced during the era of the G50... so very likely it is of similar length (i.e. longer than 915).

And, it is SIGNIFICANTLY wider. If this is a Type 1 car we are talking about, you may as well remove your frame horns altogether. I think that by the time you are done clearancing, they will be useless. On the right-hand side, you have the longitudinal output shaft and the diff. On the left-hand side, you have a big, wide ATF sump.

But, even at that, size isn't going to be the major hurdle to your conversion. The Tiptronic is a modern, sophisticated transmission. Gear selection is handled electronically - part of the engine computer decides when to shift. This is in place of the traditional valve body and whatnot. So, to make the transmission work, you're going to have to make a computer. Or, you can buy an aftermarket tranny computer for a couple thousand dollars.

I suppose that if you wanted, you could very likely make the thing
manually-shifting without too much research. I *believe* that there are basically electronic solenoids on the tranny that control the hydraulics to shift gears, so if you can manipulate these, you can probably do gear selection. Of course, you still have to build a blackbox computer, only it'll be far simpler, and you still have to create a shifting mechanism. I'm not positive of what I just said, but pretty sure.

I don't know how familiar you are with electronics fabrication, but if not, then I'd steer away from the Tiptronic. Sorry...

Take care,
Shad Laws
LN Engineering - Aircooled Precision Performance
http://www.lnengineering.com

[effvee]

Detroit makes a "World Transmission" totally electronic I have some understanding of it, but than again I really don't want to re-invent the wheel just to have some fun. And again Shad big thanks for your time.