Missed shift - how bad is the damage likely to be?

[dtfastbear]

Tristan,

Thanks for the tip! I tried your method on the way to work today and it works great. Like you said - make it second nature then you never have to think about it again.

I'm anxious to try it on the 911 since the effort for shifting in that car is much higher. I'm coaching my wife on using this technique now, too.

Thanks again,

Dean

[911pcars]

The grip postion described seems a little awkward; rotating the wrist 90º CC everytime you upshift. I think one comfortable hand position on the knob for all gears is most efficient.

Although repetition helps the process of shifting, you still have to pay attention (however little it takes). I think it's better to have a mechanism where the shifting motion takes you to the desired gear without a conscious effort to get it right. When you're trying to drive quickly, there are many things to think about; where you are, where you're going, where others are, how fast you're going, when to accelerate or not, when to brake or not, observe engine rpm, etc. And there are mechanical operations to perform; modulate brakes, steering input, heel-and-toe, match revs and throttle input, etc. Maybe my mind doesn't work that fast and probably why I'm not that quick.

That's why I developed this mechanism.



It allows the driver to concentrate less on shifting technique and more on other important aspects of vehicle control. F1 drivers have the same things to think about and perform, but wheel-to-wheel racing at 200 mph, decisions must be made in split seconds while still driving at 10-10ths. Thus the use of paddle shifters to allow them to concentrate more on driving than shifting and matching revs.

Sherwood
www.seinesystems.com
http://members.rennlist.org/911pcars

[Ho Hum 74]

Of course you have a vested interest! Belive me there is no 'awkwardness' in the rotation because as you reach the top of third you rotate 45 degrees left and then as you pull for 4th the hand naturally slips down on the left of the shifter.

Here's what's even better about this method: now that your hand is in this 'awkard' position all you do is push away from your body with your palm, towards the right hand top corner for 5th. Now what is simpler and more confident than that? You absolutely know you're going to get 5th instead of 3rd.

Tristan

[snowman]

Get the good valve springs. If you have a little extra wear, or hp loss, so what!! Its a whole lot cheeper than new valves and pistons. If you are a good driver you will not miss the hp or additional wear.

PS
The shift gate mentioned is an excellent idea. Cheep insurance.

[911pcars]

"Here's what's even better about this method: now that your hand is in this 'awkard' position all you do is push away from your body with your palm, towards the right hand top corner for 5th. Now what is simpler and more confident than that? You absolutely know you're going to get 5th instead of 3rd."

Tristan,
Upshifting from 2nd to 5th is usually not the problem nor are there dire consequences as a result. It's coming down from 5th to 4th where one can select 2nd instead. At speed, that's around 8500 rpm you're asking the engine to do. Several guys here have done this and experienced the damage that followed, and they're all good drivers too. It's not a matter of knowing how to shift the 915; it's trying to concentrate on several things at the same time with an inherently unforgiving shift setup. Mental errors are inevitable no matter the level of competition. The goal is to minimize the possibility as much as possible.

It seems you have this under control; others might find this mechanism helpful. Sorry for the commercial push, but I think it's cheap insurance.

Sherwood

[Porsche_monkey]

OK Sherwood, I'll bite. How much?

[dtfastbear]

I think you misread Tristan's last post. He advocated this rotated hand method to go from 3rd to 4th to take away any muscular tendancy to pull towards 2nd. This is the shift that cost us a top-end.

Then, in his second post, he said that it is also appropriate for the 4th to 5th upshift so that you don't accidentally get 3rd - this is also a "risky" upshift that could have the same consequences. No one ever said anything about 2nd to 5th...

That being said, I don't disagree with you, Sherwood, that mechanical assistance and safeguards are also useful. However, what Tristan proposed already feels natural to me after only doing it for a day in my commuter car. And, it makes perfect sense that it turns your natural muscle movements in the right direction for the next gear.

I'll take all the safeguards I can get - mechanical and "natural".

Dean

[911pcars]

PBH,
Wayne carries them. Go to the following link, then click on the words, "Gate Shift" in the left column.

http://www.pelicanparts.com/catalog/shopcart/911M/por_911M_pedals_main.htm

Pelican's description doesn't mention it, but the Gate Shift kit also works with 901-5 speed gearboxes using a 915 shift housing.

Sherwood
product info