Facts and Fictions Sportomatic

[Original Poster]

Original post......

[Hpt911]

I second to that. SPORTOs are a lot of fun, specially up and down the streets of San Francisco. SAVE the sportos please!

H

[Bullethead]

Great starter Raj, thanks. Save the Sporto! If people that swapped them for a standard box actually drove a Sportomatic right, they'd be converts. One of the things most don't realize is that it's impossible to slip the clutch. I've got one of ours almost finished with a full restoration, and when it was disassembled, there was NO WEAR on the most of the driveline components. The car had 111,000 miles on it when purchased 6 years ago with one clutch replacement at about 92,000 according to the PO; it had over 190,000 when we took it apart. The T engine was almost perfect as well... with a servo doing the clutch actuation, there's less stress on everything.

Maybe they'll be like the Notchback and gain more interest. So many got cut into cabs there aren't many left. They didn't build that many Sportos to begin with either. It's a shame that US testers in particular didn't grasp the benefits, instead describing them as automatics. The transmission's debut at the Nürburgring's brutal 84 hour Marathon de la Route should have had greater influence. For lack of one pedal, the "manly men drive manuals" BS has persisted.

[72targa]

Announced in Europe during 1967 was a surprising new Porsche 911 option that went to America for '68: Sportomatic, Porsche's first automatic transmission. Devised by Fichtel & Sachs expressly for the United States, it was, said Car and Driver, a throwback to "Detroit's bizarre efforts at clutchless shifting that died a merciful death in the middle Fifties."

That description was apt, as Sportomatic was another semi-automatic transmission: specifically, a four-speed Porsche manual gearbox operated by a three-element hydraulic torque converter with a single dry-plate clutch.

Road & Track described it this way: "The converter is a 'loose' one, with a stall speed of 2600 rpm and stall torque ratio of 2.15:1; its oil supply is common with the engine's, adding 2.5 qt. to that reservoir. The clutch is disengaged by a vacuum servo unit that gets its signal from a microswitch on the shift linkage; thus, a touch on the shift lever disengages the clutch. The gearbox is the usual all-synchro 4-speed unit but with a parking pawl added."

Gear ratios differed considerably, though. The Sportomatic's first through third were all numerically lower than the manual four-speed's, while its fourth was slightly higher. Its final drive was numerically lower, too. With that, a Sportomatic L was slower off the line than its manual counterpart but almost as fast all-out. Helping performance was a very high converter efficiency of 96.5 percent.

Driving with Sportomatic took practice. As R&T explained: "For all normal acceleration from rest, D (2nd gear) is used. The converter lets the engine run up to 2600 rpm immediately and...gets the car moving briskly, but noisily...A direct shift to 4th at some casual speed will be the usual upshift. For...vigorous driving, the Sportomatic is just like the manual 4-speed except that one shifts without the clutch...We found that the best technique was to engage 1st gear, let the clutch in (by taking the hand off the stick), 'jack up' the engine against the converter while holding the brakes, and release the brakes to start."

The technique was a little hard on the transmission but good for 0-60 in 10.3 seconds and a standing quarter-mile of 17.3 seconds at 80 mph. Car and Driver did better: 9.3 seconds to 60 mph and 16.8 seconds at 82 mph in the quarter. "There's absolutely no trouble in shifting," the magazine asserted. "Just grab the lever and move it. No matter how fast you do it, it's impossible to beat the clutch or the synchronizers."

In effect, Sportomatic was a compromise answer to the penchant of U.S. drivers for lugging along in high gear at low revs, thus fouling plugs and otherwise loading up engines. It was also perhaps a nod to the American preference for easier drivability than previous Porsches offered.

Where the 911's high torque peak meant lots of manual shifting, R&T found that Sportomatic allowed one to stay "in 4th gear down to ridiculous speeds like 20 mph and still accelerate smartly away with traffic. The 911 engine likes revs, and the converter lets it rev." Unhappily, it also made for more engine noise, which R&T likened to that of "a GM city bus."

Viewed objectively, Sportomatic was a typically well-judged Porsche response to a perceived need, and it didn't much hurt performance or mileage. Yes, declutching by mere touch was disconcerting (one wag suggested putting burrs on the shifter, to be removed after 500 miles), but drivers grew accustomed to it.

Still, it wasn't the sort of thing most Porsche fans could endorse, and by the early Seventies, demand for Sportomatic in the United States was practically nil. Regardless, the option would be available to special order all the way through May 1979.

Reference:

http://auto.howstuffworks.com/porsche-911-history5.htm

[edmayo]

I'm with you RAJ, back in the seventies ours was the only shop that would work on sportos, I loved them. What I really wanted was a sporto S, thought it would make a good autocross car, did own a 74 sporto for awhile, loved it for commuter traffic, sold it to buy a 72S.

[obrut]

I wonder have many sportos are converted by people who don't also have a manual? I think it is a far easier decision to leave the sporto in place if you also have manual to jump into when desired.

In my recent search for a targa I considered 2 sporto's. One the seller decided to keep (originally chartruese no less...) and my offer on the other was refused.

In either case, I would have kept the sporto for the originality/unusualness factor - especially as I was looking for a 'mellower' car to cruise about in. However, in reference to my question above, I am lucky enough to have a manual in the garage as well.

[MrJTP2001]

I'm with you RAJ, back in the seventies ours was the only shop that would work on sportos, I loved them. What I really wanted was a sporto S, thought it would make a good autocross car, did own a 74 sporto for awhile, loved it for commuter traffic, sold it to buy a 72S.

Your right Ed, it is a great autocross car. I have a few trophys from club racing when I was in the Chicago club back in the early 70s. All you need to do is put the transmission in 1st and keep your hand on the shift lever, with the RPMs well above stall just let go of the shift lever. Ah, all that extra torque. Then for the 1st to 2nd shift just slap the lever from 1st to 2nd being sure to not let your hand linger on the shifter, and with the gas pedal on the floor. The shift takes place fast enough so that you don't over-rev the engine and you're still at stall with all that torque. Loved it! I should have mine back on the road within the year but I don't think I'll be driving it like that anymore.

[boxster03]

Fiction might be that most people that ordered them liked them. Thus why so many were changed out.

[ST Man]

My 68 S Targa was a sporto. I really really loved it, but due to struggle with spares I changed to manual. I want to drive the car every day when needed and not wait for the gearbox parts. Kept all the bits for later change back if I can get spares.
I must say the S with high reving engine had a slow take off but when that car is moving it was an amazing drive. I actually raced the car with Sporto in Porsche club time trials. My class was not the most competitive but I still won the seaon with a 100% stock sporto targa.
I pull off in fourth and continue to 220km/h!!! Was a slow pull off but what a party trick.
She is now being rebuild after minor incident with BMW X5 and 40 years of wear and tear and will be used at my wedding in May

[Bullethead]

Beautiful car... were your problems gearbox internal or related to the vacuum system? Is it difficult in general to source parts in SA?

BTW, my '68 S is close to yours, #236