915 Stock Shifter Improvement Spring

[Travis Neff]

Got my spring in the mail last week. I just put it in along with some fresh bushings. It is great. Thanks Karsten!

Also, this was a factory short shifter, I had an extra stick - I cut it right after the bend and welded it on. Tall stick now!

I have an extra tall rennshifter with a top mount knob on my other car and this feels pretty close to it! Can't wait to take it for a spin tomorrow.

[BLK76911]

Nice, waiting on mine.

[bavaria911]

Karsten,
Sent you a PM from Germany, your neck of the woods.

Scott

[BLK76911]

Originally Posted by bavaria911

Karsten,
Sent you a PM from Germany, your neck of the woods.

Scott

Good morning from my neck of the woods, wasn't worried, still waiting on bushings and such, have a wonderful day Karsten !

[pjm1]

Karsten,
Just wanted to say thank you for your spring. We installed it and it works really well - I like the feel quite a bit and it is such a great idea.
Take care and thank you again!
Pete

[BLK76911]

Karsten, spring arrived in my neighborhood the other day, Lol, will hopefully put it in this weekend, thanks !

[alexandervdr]

I did install the spring today, it took 10 minutes for the spring , and ....the rest of the day for disassembly and reassembly of the console of my 86 Targa with AC. What a pita...

Regarding the spring, I did not like the 'visa-grip' method to mount it. I used a bent steel rod instead with one end in the spiral, and the other side resting in the 'U' of the spring. Less brutal method. That took 1 minute of the 10 minutes mentioned, the other 9 minutes were failed attempts with the vise-grip that I could not push deep enough to snap the spring in place.

Went out for a drive, and this simple mod works great! No more guessing where the shifter is . Tnx Karsten!

[Karsten17]

Hey Alex,

Thanks for the hint with the steel rod - a smart way to get the spring in position!

Enjoy it now and stay safe
Karsten

Originally Posted by alexandervdr

I did install the spring today, it took 10 minutes for the spring , and ....the rest of the day for disassembly and reassembly of the console of my 86 Targa with AC. What a pita...

Regarding the spring, I did not like the 'visa-grip' method to mount it. I used a bent steel rod instead with one end in the spiral, and the other side resting in the 'U' of the spring. Less brutal method. That took 1 minute of the 10 minutes mentioned, the other 9 minutes were failed attempts with the vise-grip that I could not push deep enough to snap the spring in place.

Went out for a drive, and this simple mod works great! No more guessing where the shifter is . Tnx Karsten!

[NorthernThrux]

Update. Several months after I had hoped to do this, I finally got around to installing Karsten’s spring and my shifter gate for the 1-2 gears, copied more or less from the Seine Systems gates.

So now I have a 915 with gates on 1-2 and no tension on the selector mechanism in the gearbox. Best of all worlds.

You can read about the instal in my thread on the Early S forum. https://www.early911sregistry.org/forums/showthread.php?155077-Converting-to-a-gated-shifter&p=1071850#post1071850

[bavaria911]

As Karsten stated before, he discussed the spring tension to a few of the old 911 gurus that worked for Porsche In the day and they said it had zero impact to the transmission.

[NorthernThrux]

Originally Posted by bavaria911

As Karsten stated before, he discussed the spring tension to a few of the old 911 gurus that worked for Porsche In the day and they said it had zero impact to the transmission.

Perhaps, although that’s not what they said. He reported that they said there might be “certain wear” but that the time spent in 1 and 2 wasn’t a lot. Well, I drive in the city and the time spent in 1 and 2 is a lot. And if there was no issue, one has to wonder why the factory put tabs on the right to keep tension off in the 5 and R positions. Maybe, just maybe they knew something about the engineering of their gearbox. I know some have argued that 1 and 2 aren’t used that much. By that logic R is used even less and Porsche chose to put a tab there too.

While it is 2 minutes work to remove the 1-2 gate, I see no downside and the upside is it works exactly as Porsche designed the 5-R side.

[kltarga72]

Installed mine a couple months ago and have driven more than two hundred miles since installation. Great improvement for 915 tranny.

[bavaria911]

I was in Germany last week and spoke to a German Porsche wrench that worked in the race department for Porsche in the 80-90s and now has his only shop outside Würzburg.
I spoke to him on the spring and he also confirmed the stress/wear is not for one to worry about.
Armin is a well know expert and I will trust his opinion.
Scott

[NorthernThrux]

I’m sure you are right. Even if there is wear, other parts of the gearbox will wear faster, so it’s unlikely to be a failure mode.

I do wonder why, when Porsche was cutting corners left, right and centre in the early seventies and had just redesigned the shift tower for 1973, that they went through the expense of keeping the gate tabs and the corresponding tab on the gear lever, and indeed kept them all the way to 1989 I think. There has to be a reason. It could just be a NVH issue. The tensioned gear lever would vibrate more without a hard point to rest on that the tabs provide.

[NorthernThrux]

Just to clarify my earlier post. Porsche went to the trouble of adding the gated tabs and spring loading on 5 and R in 1973. The 1972 and earlier 915 and 901 shifters didn't have it. So unless they were high on German beer, there was a reason for this decision.

[Nditiz1]

@NorthernThrux - You are making your kit available? Cost?

[NorthernThrux]

Nope, sorry. I have a day job. This is just a hobby.
You could buy the Seine systems gate kit and only use their bracket in addition to Karsten’s spring. But that would kinda defeat the cost effectiveness of his solution and mine. Maybe people can convince Seine to sell only the bracket and the tab that welds to the gearshift for a reasonable price. I’m a firm believer in keeping our innovative vendors in business, so they are there to develop solutions for our cars.

[Tyson Schmidt]

Originally Posted by NorthernThrux

I’m sure you are right. Even if there is wear, other parts of the gearbox will wear faster, so it’s unlikely to be a failure mode.

I do wonder why, when Porsche was cutting corners left, right and centre in the early seventies and had just redesigned the shift tower for 1973, that they went through the expense of keeping the gate tabs and the corresponding tab on the gear lever, and indeed kept them all the way to 1989 I think. There has to be a reason. It could just be a NVH issue. The tensioned gear lever would vibrate more without a hard point to rest on that the tabs provide.

Easy answer.
You can spend hundreds of miles driving in 5th gear. With the spring tension pushing the lever over, and the lever unsupported, it can transmit a lot of noise into the cabin.

With my Wevo shifter in my race car, in 5th gear it fairly noisy, but if I push the lever to the right to relive the spring pressure, it’s significantly quieter. (Doesn’t have the gate shift)

[NorthernThrux]

Tyson, That's consistent with something Ed Mayo mentioned on the ESR Forum. The '72 915 had a whine in 5th gear apparently that could be silenced by pushing the gear lever over a bit or playing around a lot with the linkage. But it doesn't explain why R has it too. Most people would not even reverse a mile in a lifetime of driving their car. OTOH they would never spend enough time in R to wear anything out either. So it's a bit of a mystery.

[Psychepilgrim]

Hi, great idea, you have a PM.