Not a Sixer myself, but just curious as to what the purpose was for providing a floor mounted throttle lever within inches of the gas pedal on the 914-6s??

Carburated Porsches of that vintage do not have a cold start warm up, which is why there is a hand throttle, that can also be used as sort of a analog cruise control of sorts.

So Perry, it sounds like it functions as an old style manual choke!? ...yup, I'm old enough to remember them - had one on my 68 Opel Kadette!

I presume you pump the pedal a few times, then pull it up a bit as you would in cold starting a Cessna 152/172 - to cold start a 6??

Don't know if I'd want to be leaning down to adjust that "cruz control"

For both purposes, you'd think Porsche/VW could've found room on the expansive dash for a more convenient pull knob throttle/manual-choke.

I used to understand why these are there, but have lost the knowledge. Know that my '70 911E (MFI) had it. My '73 911t CIS has it. Particularly confused as to why the "T" has it, since it has a cold start injector?
Pat

It doesn't change the fuel mixture, it's just a manual "fast idle".

My "Frankenporsch" has one... it's useful for getting the engine warmed up.

The day I drove the car home, I didn't realize what that was for and I thought it was part of the heater control (it was rather cold at the time). I got the car home and the first thing I did was to call the PO in a panic asking why the car he just sold me was idling at 2200 rpm. D'oh!

Thanx Perry,

IIRC - a manual choke on carbs doesn't change the mixture per se, but rather limits (chokes down) the throat area with the choke-flap - thereby leaving the accelerator pedal travel to operate through the full range.

It sounds like this operates to increase the throttle speed itself - thereby increasing the fuel component mixture in the opposite action (same as pressing the gas pedal a bit), but would limit the lower end of the accelerator pedal operation.

....ergo, Ken's 2200 rpm "free idle"

The function is the same as the cold start device in my 73 2L's D-jet system, kicking up the idle a few 100s rpm while cold, but done manually.

IMHO - they still could've put that sucker on the wide-a** dash for easier access.

Maybe I'll find a nice 914-6 for myself one day, and actually have some dough left over to buy it after restoring my 73 2L!

...either that, or take another 914-4 & do Raby upbuild to 2270 or more, for more HP/TQ at less weight than that 6, for fun DD!

....but I'm sure the wife will put the kabash on that plan!

Its a mechanical extra set of linkage that goes to the carbs.
It pulls on the carb linkage and its purpose is to allow the owner to hold idle at say 1500 while they wait for the car to warm up.
Once driving, you need to push it back down.

Rich

Yeah Rich, it does that on carb's cars, as well as MFI and CIS cars. Helps a lot when it's working properly.

Back in the late 70's, I had a sporto 911E, and was living in Kentucky - working in Cincinnati. Came accross the bridge into KY at about 110 - KY trooper waiting! Stopped me about a mile up the hill. Told him I lived 5 miles away & the throttle was stuck. Just needed to nurse it home to fix it.

Looked at me dubiously & asked that I fire it up. Reached between the seats & pulled the lever up, started it, and the engine fired up to high rpm's. Shut it down quickly & told the officer "stuck linkage - I can fix it at home, but not here".

After a couple of minutes, he offered a tow. Told him it would wreck the front pan.

So, he told me to go home, but keep my foot on the brakes to keep the speed down, and turn the motor off & on when I got onto side roads. He followed me until I left the freeway, while tapping the brakes regularly to ease him.

Once I left the freeway, and he was gone, I drove the rest of the way at 30 mph.

True story!

I'll bet it would still work today. Who would know an old Porsche has a hand throttle between the seats?

Still don't understand why they have them on CIS motors - never used mine.
Pat

I thought we were talking about 914/6 cars which are all carbs.

Rich

Well Pat....being the Guru he is ....has expanded this to the tail-draggers with the floor throttle levers too!

My same question applies in any case, as does my comment of why not put it on the dash where it's more accessible!?

Hey Pat, did you ever fix that paint chip on your 914?

They are installed on CIS engines because that's how you activate the cold idle enrichment function. The shops were, in the past, littered with 911s with exploded airboxes because owners didn't use the hand throttle. (That's what prompted my friend Jan Bieren to invent the cool little Backfire Pressure Relief Valve you see on so many CIS cars, mostly on replacement airboxes ...........). BTW, the hand throttle has to be calibrated in order to work properly. Seems to me it first appeared in 1969, with the introduction of MFI. Later CIS cars use a temp sensitive mechanism for cold idle enrichment, and it IS NOT the same as the cold start enrichment circuit, which is controlled solely by the thermotime switch and starter activation.

The hand throttle simply pushes a little block clamped to the throttle rod (911s don't have a throttle cable). The location of that block is adjustable. If they were to have mounted the hand throttle on the dash like a choke pull knob, there would be a lot of monkey motion levers, cables, and connection pieces added to the mechanism. Simple most often is best, and this elegant system was applicable to carbs, MFI, and CIS, over nearly a decade. Now you know.

The Cap'n

Thanx Cap'n....."Wery Interesting" - as Arte Johnson on Laugh-in used to say!

By the same token, moving the lever closer to the driver's seat could've caused all sorts of confusion with the heater lever, to disastrous results!

I always liked the trouble free (usually) automatic Cold Start Valve (CSV) on my 73 2L's D-jet.......no worries....most of the time....

...until our Pacific onshore coastal salt air got in & corroded electrical connections on the EFI - esp. when I lived 3 blocks from the beach in Huntington Beach & even with a closed garage!

If you lived in Huntington beach, your CSV NEVER activated. It was never cold enough for it to come on. The Cap'n

I thought I'd impart a little experience, since many sixers have MFI and CIS systems, aside from the carbs.

Sorry, I'll just shut up.
Pat

Not in HB -

...but then I did go places like Big Bear, Arrowhead, Mammoth, Tahoe, Brianhead/Cedarbreaks, Park City, Ashland, etc. & assure you that the CSV did activate there!

...heck, I still even have ski racks & a set of chains for the 165HR15s for the Teener!

In fact, I'd even done the Body Surf 1/2 day at the Beach & Ski 1/2 day in the mountains - ALL in ONE day thing - on several occasions!

...also went up north during winter part of Rugby season to play games when it was actually cold enough to kick in the CSV!

They did allow us to leave HB every once & awhile ~
...don't they let you out of Santa Maria Krusty??

FYI All Y'all - the above are mountain ski resorts/areas with winter weather....

Hey Pat, I'm sure others enjoyed the input, given the wide range of replies on both the 914-6 & 911 sides!

...I am!!!!

Kruster,

Look, I know this could be construed to be, well hell it is, non-original text. But since we have it started....

Many teeners have CIS motors in their 914s. How is this hand throttle calibrated ?
Pat

Every once in a while I forget to push the lever down all the way after warming my 2.4S MFI up. When shifting in the 1800 - 2200+ rpm range the car feels very zippy. It makes the car really want to go since the S cams and MFI doen't really bring the engine to life until 3000+ RPM's. I sometimes pull back on the lever when driving backroads to keep the RPM's up.

Sorry guys... the hand throttle is simply a rod that actually goes "forward" to the pedal assembly.

The bell crank on a 914-6 pedal assembly has a wing off the side that this rod pushes against, effectively pushing your pedal down for you. When you lift the hand throttle you can actually see the pedal go down.

No extra linkage to the carbs and no blocks.

finally someone gets it right ..lol

Ergo, back to my comment on why Porsche couldn't have put it in a more convenient spot on the dash - it still stands.

Even if it cost a few DM more to link it down to the gas pedal's bell crank - the dang 914-6 cost 180% of the 1.7L 4 new - so I'm sure there was room in the budget for a properly designed instrument set-up!?

Because the way it stood, it was simple and it worked. It's only used for cold starts so why make it more difficult than it needed to be. It's only on rare occasions that I use it anyway.

All the books that I have read on the 914 said that the cars were just too expensive to make for what they were selling them for. So I guess they would argue with you on that.

I like where it is... I'd hate to have something like that cluttering my dash. So, I guess we're down to personal preference.

Eric, I didn't mean to put that lever on the dash!

I meant just to add one more pull knob to match the others on the dash face (head & fog lights, flasher, lighter, etc.), with a shaft & cable or other connector "behind the scenes" under/behind the dash to actuate the accelerator bell housing movement.
...with an appropriately colored & lighted bezel & identifying insignia of course!

To me, that would be a much cleaner & more aesthetically pleasing - as well as more functional & more safely operated control - than is their lever up near the gas pedal where it can be accidentally triggered with your foot, or forgotten that it's still engaged, as others have stated so far!

...some intentionally, as in Pat's story!

It seems that location is just one of those little Porsche quirks!
...anyway, my commentary above runs along the lines of any other design second-guessing we all have done at some time or another!

Thanx to all who've answered my basic question at the start - of why it was there & what it does. Cheers All!

Hopefully it's been a useful discussion to others out there with or wanting a 914-6!

I remember asking a question here at one point (actually, about the carpet finish around the hand throttle, go figure) as to why something was done in a "cheap" fashion when making it nice would have been so easy. One response I got was, because form follows function. At time time I thought it was just somebody's flip answer to my newb question, but I've since come to learn that it was actually a Porsche design philosophy, and one that I've since come to appreciate. There's an elegance to it.

That aside, I could swear I read at one point that the hand throttle was used by racers who actually started the race outside of their cars (physically), and then ran and jumped into them to start the race. The hand throttle allowed them to have the car warm and ready to go when they were. I dont' think I'm making this up, but admit that this memory is a bit, eh, shaky.

Reid

So having bought a factory 6 car and have the lever and the carbs, Does anyone have photos of the connection point at the carbs. I plan on a 100% stock car

Hey there Orange Teener!

According to Eric's post above from the bottom of the first page on this thread, it's not at the carbs, but rather at the accelerator pedal bell crank.

Try to PM him at that post to see if he has a pic or 3. BTW - Eric's PMB does excellent brake caliper restorations & carries some of the parts you'll need (see link at the bottom of his post).

Cheers!
Tom in Orange

I must have Skimmed right by that

.....The hand operated /pull/push rod.....was one of the parts in the JC WHITNEY open exhaust pipe valve kit... loads of fun screwing with the minds of the local keystone cops....your probably to young to remember this stuff..... sometimes the push pull /pushrod operated a/ the "FOGGER'....putting oil into the exhaust manafold for a continious bellowing blanket of moquito control... also hilarious... ...

Hey!.....I remember, a neighbor up the street in San Diego in the late 60s had one on his 500 hp `69 Z1 Camaro Z28, which was bone-shaking when the pipes were "open"!

But this is off topic & I don't want to get Pat mad, as there's losta Sixers involved here on my O&H question! ....since you can probably recall this JCW item too - be nice on this side-humor Pat, pleeez!

You know, there are sometimes(for the sake of humor), that "diverging" from the topic is kinda cool.
I'm not a total "prude" when it comes to sharing the joys of owning a hot car in the late '60's. Or, knowing the guy next door who had one. But, nonetheless, we should take those experiences to the Sandbox - which I will do now.

No harm, no foul guys. Let's just take it there. Hell, I'll start! See Sandbox.
Pat

When I sold my factory six, I kept most all of the parts for my conversion car. The hand throttle is something I kept. If you'll look at ALL 914 shifter base, you'll see that it has a cut out on the right front side. The bodies are set up to use the hand throttle. All it takes is the parts. The accelerator lever, 914 423 260 00, has a "wing" on the side that the hand throttle rod contacts to press the pedal down. If I didn't have it on my conversion six, I'd want one. Anyone with a conversion six or even a four with carbs could mount one if they had the six hand throttle parts. In the pic, number 22 is the six lever and number 19 is the four. They are the same except for the "wing" that is on the six that the hand throttle rod contacts.

Click to view attachment

GEE whiz...I thought it might have been a factory option, just for the 914 -6 guys....and porsche found the "trick" race parts supplier and...then ....and then ....

The throttle control was just like the heater control and was on opposite side of the tunnel. The throttle control was black which differentiated it from the heater control. The factory also provided an owners manual to provide instructions on the operation of the controls among other things. I sold them new and had several for demos, and that seems to be how I remember it. Al.