TRANSMISSION (Last update: 08/01/2006)
After 156,000 miles, another overdue breakdown finally happened. The throwout bearing seized and flew apart, destroying the clutch disk, damaging the flywheel, and making a small penetration into the transmission case. Since the breakdown occurred while returning from a road trip, I had to leave the car with mechanics in Georgia and I was not able to get pictures of the actual parts or the install. The only good news in this story is that the car broke down within about 10 miles of Road Atlanta raceway. After talking to the tow truck driver about what I was doing with car he knew exactly where to take it.
The cluth, flywheel, and differential noted below were all installed by Ken Hensley at Hensley Automotive Service in Hoschton, Georgia. Many thanks to Ken for his patience and expertise.
Clutch Masters Stage 1 Clutch - Rated for 220 ft/lb torque.
Seizing this "opportunity" for an upgrade, I purchased a Stage 1 clutch from R&R Racing along with their braided stainless clutch line to replace the stock parts. The maximum torque rating for this clutch (220 ft/lbs) is more than I will ever need for this engine. I can aggressively engage it for autocross, yet it should engage smoothly enough for daily driving. The braided clutch line eliminates any mushiness in the clutch pedal and makes every engagement as crisp or controllable as I need it.
** Note ** After the installation (and getting the car towed all the way back up to Maryland), I've noted a slight pulsing in the clutch pedal during low speed engagement. I believe this may be due to the new flywheel below. I'm investigating the cause at this time and using this time to work on my brakes.
MX-3 (1.8L V-6) Flywheel
While the clutch was being replaced, it only made sense to replace the stock flywheel using a lighter weight flywheel from a Mazda MX-3 (1.8L V-6) and try to gain a few extra horsepower in the process. This was ordered from Kragen auto parts online. This is a common and proven modification. Some folks will say that you need to do some milling to the flywheel and reduce the step height to .787 inches to get a firmer engagment with the pressure plate, and reduce chatter and disk glazing. This is covered in the instructions that come with the part. Bottom line... do your research, have your references handy, and double-check with the mechanic doing the install. Whether you're doing this yourself or not, you don't want to have drop or open the tranny more than once.
Quaife Limited Slip Differential
Ok... Maybe I was a little too drunk or having a Walter Mitty moment. This is probably way too much for what I need, but one of my buddies is extolling the virtues of this little mod when it comes to cornering power and traction control in autocross, so I had to do it while the tranny was out and "save" a few bucks.... Right? I mean, I just HAD to do it.
I bought this Quaife limited slip differential from Tony Woodford at AWR. Installing it does require some minor machining of the selector fork and tranny case for bolt clearance. This also is covered in the instructions that come with the part.
R&R Racing Short Throw Shifter
I'm also taking the opportunity to install the Short Throw Shifter from R&R Racing. Comes with polyurethane stabilizer bushings.
Linkage
Notes to self for future ref....
Bushing replacement write up. Link to pictures at bottom of original post.
