Continuing with upgrades after Rusty's first experience with real competition on the track below is an improvement I hadn't considered until the cost was no longer an issue.

How I came to have a $15 Shift Knob

After being contacted by someone interested in my travails on the track with Rusty, he put a bug in my ear that perhaps a Miata shirt shifter would work in an FC. Now Iíve always been interested in a short shifter for the racecar but being the budget racer, shelling out $150 for a short shifter just wasnít in the cards. Now I wonder about this Miata idea. Lets go shopping...on eBay. Itís one of those things where the price is just so low even if a project doesnít work thereís not so much pain at the thought you just flushed some of your hard earned cash. So...Miata short shifter...$40. $40? Jeebus thatís cheap! How can it be, given the "other" FC shifters cost at least $120+ I simply had to try this. 4 days later it arrived. Looked pretty decent...for a $40 shifter. Lets see if it fits.

This is what I got for my $40: eBay Miata Short Shifter Components

Installation and Tweaks

Well it fit but there were two things that needed to be tweaked just a smidge but Iím here to say it works just fine. So lets begin. Remove the stock shift knob. Remove the trim and leather shifter cover - it snaps right out (please excuse me if itís more difficult removing the trim in a car with a full interior because my car has none). Remove the two rubber shifter boot covers. Remove the square metal retaining bracket on the tunnel and the thick rubber tranny boot. Now remove the three 10mm bolts and lift out the stock shifter and shifter cover/boot.

Lets begin with the Miata SS. But first some observations about the Miata SS "kit." The principle of the SS is that it moves the fulcrum of the shifting motion further from the end in contact with the transmission. This is why the shuft "throws" become shorter. It's not about cutting the top of the shifter. Comparing the stock shifter to the Miata SS, the SS comes in two pieces that are threaded together. The stock shifter comes as two pieces but are bonded together with a rubber isolator -they do not come apart. The slot in the fulcrum ball of the SS has a plastic insert. I'm concerned that this will wear out prematurely compared to the all metal slot of the OEM shifter but for $40 what can you say? Note also the ball at the end of the shifter is smaller on the SS...more on this later. Now on to the install.

One piece...two pieces.

Ok, first up, the lower OEM shifter bushing needs to be removed. I also found it helpful to suck out as much of the tranny oil from the top reservoir as possible. Turkey baster works great.

Removing the lower bushing. Sucking out the old "topside" gear oil.

Then the spacer bushing is dropped in followed by the stock lower shifter bushing you just took out. If your stock shifter bushings are worn out Mazda sells a shifter bushing kit for pretty cheap. Now woudl be a good time to replace them.

The short shifter lower spacer dropped in. And with lower shifter bushing on top of the lower spacer.

Next up is a thin shim/spacer...that doesnít fit. The inner hole is too small to fit over the lower bushing. No problemo. A few minutes with hand file and the inner diameter is now big enough to fit. I would suppose that the shim would fit *under* the lower shifter bushing on a Miata. We still need to use it, albeit in a different location, to ensure the SS fulcrum ball is at the right height. I applied a little bit of High Temp RTV to seal the joints both on the top and bottom of the shim.

Opening up the inner hole on the shim. Installed shim with RTV.

On top of this goes the big spacer. Note there is a small allen head bolt in the spacer to align the shifter the same way as the OEM shifter. The tranny has a pressed in "pin" to locate the stock shifter. I used a little locktight on this small bolt after it was adjusted to fit out far enough into the slot in the SS itself. Now you will note that the ball on the end of the OEM shifter is much bigger than the ball on the end of the SS. So the ďkitĒ comes with a small bushing to make up for the difference.

The small bolt in the SS spacer - adjust and use locktite. The small bushing for the shifter ball.

In theory the small bushing on the shifter ball fits into to receiver in the tranny where the old shifter ball fit...on a miata. Trouble is the SS bushing is too large for the RX7 receiver so a few turns on my belt sander and it is now the right diameter to fit into the tranny receiver. The bushing is thin so don't get too happy with the sanding!

Reciever in the transmission the SS bushing is supposed to fit into. A few turns on the beltsander and the bushing now fits fine.

Refill the top reservoir of the tranny and drop in the lower half of new SS. There, of course, is a need for a topside bushing. The bushing for the top side supplied with the SS kit did not have a notch cut into it similar to the bottom side (notch for the bolt in the spacer) so I reused the one from the stock shifter - in my case this was the blue bushing. Now since you have to remove the boot and shifter cover from the stock shifter anyways this isnít an issue although itís a struggle to remove the boot and shifter cover from the stock shifter. It is possible to slide a flat tip screwdriver in between the shifter and the rubber boot to get the lip of the rubber boot over and onto the thick part of the stock shifter where it is easier to slid it off. Don't ask me how I know. If yours looked like my original one I had to buy a new one anyway, a new boot/cover costs about $32 (Part#: M509-17-480A Boot, Dust.) So....the topside bushing is dropped into place. To check you have it all assembled correctly the top of the bushing should be about flush with the top of the spacer.

The stock upper bushing with the notch and the supplied Miata SS upper bushing with no notch which can't be used. Short shifter, upper spacer, and upper bushing installed. The top half of the SS is pictured but I'd suggest just installing the lower half to ease getting the shifter boot/cover on.

Now the shifter cover/boot can be slid over the lower half of the SS and bolted into place using the longer 10mm bolts (and flat and split ring lock washers) supplied with the kit. I then screwed on the upper half of the SS. I used a bit of lock-tight on the threads - the last thing I want is for the shifter to come off in my hand in the middle of a race! The rest is just reinstalling the other rubber boot/covers and interior trim pieces.

This is what my old shifter cover looked like when removed. Trashed. This made it easy to slide off the upper stock shifter bushing for reuse (see above). The completed Miata SS install minus interior trim and numerous rubber boot covers.

But what to do about the shift knob? The OEM shift knob has a thread that is too large for the Miata SS so off to PepBoys I went in search of the cheapest shift a ball I could find. Hence the $15 piece of crap shift ball you see pictured. All I wanted was a nice solid AL ball threaded to fit the shifter...makes me sad that what I ended up with was the best PepBoys had to offer. Still, after a short drive in Rusty the throw is nice and short and very crisp. Coupled with the new clutch I think Iím going to like it very much on the track.

Piece of Cr*p Plastic shifter ball...the finished install

I couldn't do it....that nasty cheap plastic Pepboys special had to go. It was suggested that a Honda shift knob would fit with a little help. eBay to the rescue and for $18 I had nice polished solid AL shift knob from a Honda Integra Type-R. It did require retapping the shifter threads but no big deal. I no longer feel like the plastic is going to crumble under a death grip shift going into Turn 1 and 100mph.

A quick retap of the shifter thread and now I have Honda POW-WHA! Kinda goes with the "I ShIfT mAd QuiK Yo!" Doesn't it?

Chapter I: To Begin the Hooptie to Hotrod Saga: Part 1 of the First 16 Installments
Chapter II: The Saga Continues beginning with Part 17 through 21, A Good Rear End: Part 17
Chapter III: Picking up the Pieces. Part 23 (clutch, adjustable proportioning valve + more)
Chapter III: Getting a License - Racing School No. 2, Part 25
Chapter III: The S5 Decision, Part 26
Chapter III: S4 to S5 Conversion - CRAZYNESS! Part 27
Chapter III: Oil System Upgrades, Part 28
Chapter III: More Suspension Improvements? Part 29



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This page last updated March 19, 2006

Disclaimer: All images contained on this page are the sole property of C. Regan.