Sportomatic, are you experienced?

[tgittens]

Just wondering if anyone has experience driving these strange cars. I just bought a 1969 911t and will be bringing it to my mechanic next week but wanted to get some KNOWLEDGEABLE opinions first.

At this point the gears grind and it is very sluggish off the line. My main question is this the driving experience I should expect or can these cars ever feel like a standard early Porsche?

I realize it won't ever come close to my 2.4 standard transmission, but I also think it should drive better than a bus...any experience and tips would be greatly appreciated!

[milt]

Who are you taking the car to? If there is any doubt, search TRE Motorsports on this BBS. Dave's user name is TREcup.

The sporto uses engine vacuum to operate a standard clutch. If there are vacuum leaks, the clutch won't fully disengage. Grinding gears is the result. It may be simple adjustment or some new hoses. When the sporto is working well, the car is smooth but get used to the sluggish start unless you nail it.

[tgittens]

Car is going to Dutch Treat. Robert has a ton of experience and I have confidence in him...but if he says he can't help me without changing out the transmission, I'll give Dave a call. Thanks for the advice.

[milt]

I met Robert a month ago. I've heard good things about him. I'd say you're good, but there's always TRE for another time.

Meanwhile, yes, the sportos are a little different and take some getting used to.

[Scott Douglas]

My '78 SC isn't as quick off the line starting in second or third as it is in first. Like Milt says, if you nail it there's not much difference except you don't have to finesse the clutch engagement. You just GO.
When the 'system' is operating properly, and if your trans is in good shape, I don't think you'll miss not having a clutch. I do wish you could double clutch down shifts, and I think there's a way to 'wire' it so you can do it, it would mean that the diaphragm gets worked a little bit more than it does with the stock setup.
I really enjoy mine, especially when there's stop and go traffic.

[tgittens]

This has been very incouraging! Thanks, I was worried I had made a mistake buying a Porsche with no get up and go! I think it just needs to be set up correctly.

[scarceller]

I had a 75 Sporto and it was great. Grinding like symptoms are most likely caused by bad vacuum or a out of adjustment sporto valve, the control valve really needs to be setup and adjusted correctly. Also the microswitch at the bottom of the shift lever must also function perfectly. In the end if everything is setup/working correctly these cars are great.

[gumby]

Didn't Porsche use this transmission in their race cars for Le Mons? Ron

[milt]

More like their rallye cars.

[layzee]

Story of Sportomatic in motorsport: http://sportomatic.org/marathon

[Peter Zimmermann]

Originally Posted by tgittens

This has been very incouraging! Thanks, I was worried I had made a mistake buying a Porsche with no get up and go! I think it just needs to be set up correctly.

Did you have a PPI done on the car?

Lack of power can be many things, among them ignition points not set right, timing not set right, carbs not set/balanced properly, even internal engine problems, etc. I strongly suggest that you have a major service done on the car, by someone who's been around long enough to know what a '69T is, and go from there.

During the tuneup it's highly likely that your grinding problem will be diagnosed, or at least the basics eliminated. In my experience grinding is about 60% linkage/shifter related, while internal clutch problems (oil contamination, pilot shaft bearing failure, worn out disc, etc.) are about 40%.

Of course, because the Sporto is not a true automatic, and all gear changes must be done manually, correct operator technique is also important. If Long Beach is easily accessible to you, pm me for another recommendation.

[Sgrun]

I have a 69 E sporto, and it is a blast - very easy to drive once you get used to it, and very fun to rip around on curvy roads with as well. Incredibly flexible - I don't do much city/heavy traffic driving at all, but I can see where it would be perfect for that.

I have a 5 speed car 69 as well, and if I'm forced to sell one, it would probably come down to flipping a quarter..........

Get it working right and enjoy it - don't switch it out for a manual.

Steve

[tgittens]

As to the question of PPI...yes I did and it was mentioned that the synchros needed to be done...but the more I learn about these cars the more I hope it's just an adjustment of the microswitch or a valve. I know the person who did the PPI didn't do any formal tests on the transmission so it may have just been an educated(or not) guess. I was more interested in a rust report and overall condition of engine which seems to have been reported accurately. And given the distance traveled, elevation changes, general lack of use of the car, I believe a tune up is in order!

[Fishcop]

The Sportos are great when set up. The above advice is right on the money, but I'll add the following...

The number one failure of the sporto now is it's age and the fact Porsche stopped production (thus lost knowledge) long ago - finding a mechanic from the era still working on them is hard. The main thing that fails now is the vacuum servo unit on the gearbox. This device 'pulls' the clutch for you using vacuum. The diaphragm inside is now prone to failing through cracking and perforation and the unit is NLA. The symptoms this causes is just like failing synchros, but what is actually happening is only partial engagement of the clutch.

If you do a bit of a search on this board and sportomatic.org, I think you'll find details on possible fixes including mine which involved modifying a similar sized truck brake diaphragm. Eventually I went with a manual gearbox but I know a few others have picked up the sporto repair sword.

[crater64]

I have one, bought it in January but have yet to put it on the road. Unfortunately I may have to sell it even before I do.

That said I did drive it from the trailer to my home and a couple of times round the block since then, and there's been no problems with the shifter yet, except that sometimes I grind gears going from reverse to first and that's a matter of my hamhandedness.

Ed

[9146racing]

i had the pleasure rebuilding one a while back, there were two different ones according to the build year, 905 and 925. your 69 should have a 905. it is a four speed and is actually fun to drive. you will find a nice chapter in ludwigsen book. they even raced them in 69 and were faster than the 5 speeds.
i still have extensive shop manuals for sportos and a ton of old and new parts. i think i even still have a 905 in my shop that worked perfect. your solenoids, vacuum lines, torque converter(check the oil) and your shifter base are the areas you need to check first. the clutch disk is a Audi 100 part by the way (300% cheaper then Porsche)

good luck,

[tgittens]

Wow! Sounds like I may be contacting you soon!

[9146racing]

anytime

[layzee]

Since we've got a decent Sporto thread going I appeal to owners to add your car to the registry at www.sportomatic.org/registry. We're getting a good collection on there now.

Fishcop - I researched and found the part number for the truck vacuum servo you used to replace your old one but even after trawling through Australian big-rig parts supplier catalogs I couldn't hunt it down. Can you provide any details I can put on the site?

[Fishcop]

Hi Phil, at Ed's (Crater64) request I've tried to track down the diaphragm over here, but had no luck. It was 7 years ago that I did this conversion and I didn't own a digital camera back then I'm mailing the old diaphragm to Ed for him to try and find something similar in the States.

The sporto and the modified slave unit are currently under 5 years of junk in my shed... I'll dig it out and pull it apart in the interest of photographing and documenting precisely what I did