KoB

Recently I'd decided that the stock shifter wasn't very crisp, even for street driving, and installed a Numeric Racing shifter. The Numeric shifter is a solid product and greatly improves the feel of the car. I couldn't be happier with it, but after reading a few Rennlist posts I started thinking that a heavier shift **** might enhance its performance even more.

So, I started looking into replacement *****. It seems as though pretty much anyone who uses an aftermarket **** on a 996 has to either cut the factory boot away from the OEM ****, or else use an aftermarket boot. I quickly decided that what I was really looking for was a weighted **** and an aftermarket boot.

The first **** I looked at was the Rennline ****. It's a nicely made aluminum **** that uses an O-ring to retain the boot, but it's not quite what I wanted. I don't really like the “spun aluminum” look, and didn't think it would be quite as heavy as I wanted – although, to be fair, this was from a very unscientific inspection of one at a Rennline exhibit.

What I decided I was looking for was a height adjustable "classic" ball shaped **** with the shift pattern engraved in it, in a matte or shiny black finish. Also, I had assumed that I would be using a third party shift boot and would need some sort of retainer for a finished appearance.


The TWM Solution

After a bit of Googling, I came across TWM Performance (http://www.twmshiftknobs.com/). They manufacture shift ***** machined from stainless steel. Their ***** are not inexpensive, but I read a few reviews and decided to take a closer look. Their A6 Leopard **** in Black Pearl seemed pretty close to the **** I'd been looking for.

There was, of course, a minor problem. TWM manufactures threaded ***** and did not list an adapter on their Web site for the 996. Although I had been thinking about making my own threaded adapter, I emailed TWM to find out if they had any plans to offer an adapter for the 996. To my surprise, they responded that they had a prototype adapter available and asked if I would like to try it out.

So, I agreed to be their crash test dummy – a role which my wife would tell you I am well suited for. I ordered the A6 Leopard **** in the Black Pearl finish, with the 996 shift pattern engraved on it. The engraving really serves little purpose, as – even in my golden years – I can usually remember where each gear is likely to be found. That said, I think the engraving makes the **** look a little less like an aftermarket add-on and a little more like my interpretation of what I wish the factory had done. It's a small point, but it's my **** and my money.

Anyway, it turned out that TWM also had a shift boot in prototype, so they sent that along as well. Their boot design sounded interesting in that it incorporates the plastic piece that snaps into the center console. That piece isn't particularly expensive or difficult to source – it's Porsche PN 996.552.655.01, available from Pelican Parts – but with most aftermarket boots you'll need to cut some slots in the boot material to expose the tabs that snap into the console. You also need to trim the excess material away and use some sort of adhesive to attach the boot to the plate. The TWM design takes care of all that. Again, it's sort of a minor point, though I've messed up an aftermarket boot or two trying to fit them to the plate.


The Unboxing

The Black Pearl finish – actually, sort of a glossy gunmetal – is made to order by TWM, so it took a couple weeks for my **** to arrive. The box contained the ****, the prototype threaded adapter, the prototype boot, and a small bag with zip ties and set screws.

The adapter and hardware:




The boot, top and bottom:





The **** and adapter are cleanly machined and very solid. The **** weighs just over a pound:




The adapter is another 180-odd grams:




TWM was very generous in sending me a boot to use with the adapter and ****. It's a prototype that I'll be exchanging when the boots are actually in production; this is why I have a gray alcantara boot in a black leather interior. Alcantara isn't my thing, but the boot is well made – the stitching is straight and even – and fits properly over the mounting plate without bunching or excess. If I were installing it again, I might use a dab or two of weatherstrip adhesive to fix the boot material against the mounting plate, but that's really not necessary; it fits well as is.

Installation is pretty straightforward:

• remove the existing **** and boot. Here's my Numeric shifter in all its naked glory:
  
  
  
• slide the adapter down the shifter shaft and tighten the top two set screws
• position the lower jam nut toward the bottom of the adapter and tighten the bottom two set screws
• thread the **** onto the adapter and set it at the desired height – if the **** is engraved (like mine), be sure to get the shift pattern oriented properly
• tighten the top two jam nuts to set the **** height and orientation. Here's the threaded adapter in place with the **** being test fitted. Note that I haven't tightened the lower set screws yet:
  
  
  
• remove the **** and put the shift boot over the shifter shaft
• reinstall the ****
• raise the boot over the ****, making sure that the boot is inside out
• secure the boot to the neck of the shift **** with a zip tie and cut off the excess. Here's the boot in place and zip tied – I haven't cut off the zip tie yet:
  
  
  
• pull the boot down into position and snap the mounting plate into the console. Here's the finished installation:

Notes on Installation

• The set screws use a 3/32” Allen wrench. Before installation, you might want to make sure you have more than one handy. I dropped one between the seat and console and haven't bothered to fish it out; fortunately, I had another on hand.
• The TWM threaded adapter is sized to fit the stock Porsche 986/996/987/997 shifter shaft. As shipped, it does not fit the Numeric shifter shaft, which is slightly thicker. I used a 1/4” carbide burr on a die grinder to remove a bit of material from the inside of the TWM adapter so that it would fit cleanly over the Numeric sifter shaft. This wasn't a big deal, and I don't fault TWM at all. They are selling an adapter to fit the stock Porsche shifter, not another vendor's aftermarket product.
• The set screw holes in the lower jam nut needed to be cleaned up just a bit before installation. Again, this wasn't a big deal, and it's important to remember that my adapter was a prototype. With anything like this, it's a good idea to test fit the parts before installation.
• I used a bit of anti-seize compound on the inside of the shift **** before threading it onto the adapter. That probably wasn't necessary but I didn't think it could hurt. The **** threads down securely and with those jam nuts in place, it isn't going anywhere.

Ratings and Driving Impressions


Fit and Finish: 10/10. It probably isn't fair of me to comment on prototype parts, so this rating is for the **** only. The finish is flawless – a hard, glossy coating that looks great and seems to resist fingerprints. The engraving is clean and even. The **** is perfectly smooth; I didn't measure it for accuracy, but it sure seems spherical. The threads (¾ – 16) are cleanly cut and very deep, allowing the **** to be positioned over at least an inch of height variation.

The adapter is also very cleanly machined. Before installation, I chased the threads with a 3/4-16 die just to ensure that the jam nuts would thread cleanly over the holes for the top two set screws. This was probably unnecessary. The set screws themselves are shipped with thread lock installed. The only issue I noticed was that I had to clean a bit of metal flashing off the set screw holes in the bottom nut. This took all of a couple minutes.

The adapter and **** fit solidly to the shifter shaft. There is no wobble and no sense that anything will or could come loose. These are high quality, well made parts.

Aside from my aversion to alcantara, I have no issues at all with the shift boot. The boot is evenly stitched and fits cleanly over the mounting plate. Material quality is good and it looks at home in the 996 interior … at least, it would if my interior were grey alcantara.

Driving Impressions: 9/10. As soon as I had the **** in place I had to try it out, so I grabbed my keys and wallet, locked the garage, and hit the road with a passenger seat full of tools, zip tie ends, etc :-). My immediate impression was a reduction in shift effort. The Numeric shifter is already very precise, but the addition of the weighted **** heightens that “rifle bolt” feeling of precision. The shift lever moves so smoothly and easily through the pattern that it may take a bit of getting used to.

I've had a couple days to drive the car around town and on the highway, and the **** is a welcome addition. The shift pattern feels even a bit tighter than it did when I first installed the Numeric shifter, which I'd attribute to the counterweighting effect of the ****. The one thing I have found is that it is absolutely suicidal to leave the **** exposed to direct sunlight, as it becomes unbearably hot. I've taken to leaving my cap over the **** when I park the car, which seems to mitigate the worst of the scorched-palm effect.

Overall, I think the TWM **** and related parts are very well made and their appearance is in keeping with the style and quality of the 996. As to performance, I think the weight of the **** adds to the already-significant improvement of the Numeric shifter. I like the size, shape, and feel of the **** and think it is a worthwhile enhancement to the car. The only trade-offs, for which I subtract a point, are the expense – as I said, these ***** are not cheap – and the tendency of the **** to get very hot or very cold depending on the weather.

porsche951

Nice write up. I'm not certain but I think my OEM Carbon shift **** is weighted also. I had an aftermarket **** on my S2000 that looked exactly like that.

jamren

Any tips for removing the stock shift **** apart from twist and pull for dear life? I have heard that a hair dryer also helps. I need to take mine off soon and am looking for an easy way….

KoB

I pretty much had to twist and pull for dear life. Helps a bit to put the car in 4th gear (or 2nd or 6th, I guess) to get a little more leverage. Seems like a heat gun would help, though I didn't try that.

zachsdad1

That was a great write up and I think you will be very happy with the end result. One word of advice. That shift **** will get incredibly hot in the direct sun. Like crazy hot. (I had a similar **** on my boxster.)

I cut a tennis ball and used it as a cover when I left the top down or when I thought the interior was exposed to direct sunlight.

Good luck with the project. Can't wait to hear your impressions of the end result.

eagle11401

Awesome write up. I had a voodoo **** that was similar in my Miata and had to keep it covered with a small towel when parked at work. They get super hot. Worth it though, an already great shifter was just that much better.

dc3843

I just bought the M1 abrams, thanks for this write up! I checked for the shift boot on their site, didn't see anything so I'm waiting on them to return my inquiry email

onewhippedpuppy

Nice! I had a Rennline **** and Redline Goods boot in my last 996. I liked the Rennline **** and the fact that it was height adjustable, but they are limited in color and have an aftermarket look. I also was never totally happy with the o-ring for retaining the boot, it tended to roll and become loose. The Redline boot did require fitment to the factory plastic frame, not hard but a bit of a pain.

A weighted **** makes a huge difference in shift quality. The standard **** is a flimsy plastic thing, the upgraded OEM ***** like the turbo and carbon fiber models have a lot more heft. Just the installation of my Rennline **** made a noticeable difference.

Imo000

Are you going to loose your fingerprints in the summer when the **** sits on the sun for a day?

KoB

Didn't lose them last summer, but I usually put my cap over the **** while the car is parked (top up or down). The **** gets warm, but not problematically so.

Surprisingly, it's not stupidly cold in the winter either ... certainly not warm, but I can shift the car without losing any skin.

Imo000

As long as it's not like the **** dude in Indianian Jones.