Introduction
The Mazda 323GTX was not been sold in this country since 1989, or over 14 years ago. With only 1,189 vehicles sold over the 2 years the GTX was available, it's easy to understand that some performance parts are just not available any longer. One of these areas is the suspension. No one has made new GTX-specific dampers in this country for years. Tokico Dirta struts went out of production several years back and very few, if any, shocks offer the kind of damping control required by the GTX's long-travel strut system. Cork Sport, an Oregon-based Mazda specialty company still imports KYB struts for the 323GTX is 3 different varieties. Leeda also makes GTX specific suspension systems, and they can be contacted for more information. Road/Race Engineering offers a coil over set-up that is used with new inserts in stock shock housings, while other GTX owners have found MR-2 and 626 struts can be fitted to the GTX. Since I was looking for a coil over set-up, and didn't want to pay more for the suspension than I did for the car, I started looking used.
Getting Started
I was able to find a set of used GAB struts from a 323 GTX rally car that was being retired due to a slight off road encounter. The four shocks were delivered with Eibach springs, sleeves, spring perches and aluminum hats. I would need to reuse my stock top mounts for the front and rear. The spring ratings are 280 front, and 150 rear. These units are beefy, I've only seen a larger strut rod on my BMW 2002 Bilstein Sports.
Installation was simple and straight forward. The sleeves were slid over the strut bodies, threading on the collars, dropping on the spring and bump stops, and then bolting the whole assembly together. The stock bump stops were used and the bellows section was trimmed off. There was still more than an inch of bump stop to save the GABs from dangerously bottoming out, but with the added travel and increased spring rate, it didn't figure to be a problem. Fitment of the GAB strut housing on the front required removing small amounts of material from the 323's upright to achieve reasonable camber settings. This job was accomplished with a die grinder and a bit of patience. Without having the car completely assembled, I have not set the ride height, and no alignment settings have been measured.
Sway Bars
Since this car will be primarily a street car, I decided to replace the front and rear sway bars with beefier units from RD Enterprises. I ordered both bars in the 1" size, and they come with poly bushings, end links, and chassis braces. Bars are available in different sizes, and pricing starts around $140 for the front. If you're doing more driving on the dirt than the pavement, it is recommended to remove the front sway bar. This reduces the GTX's front roll stiffness and enhances its ability to rotate quickly in the dirt. RRE sells polyurethane sway bar bushings and new end links for those wishing to maintain the stock bars.
6 Link Rear Suspension
With the basic bolt-on improvements out of the way, I decided to improve the rear lateral arms and trailing arms. I started by buying a set of bushings from Chaio Fang Imports, this is the same place that sell the factory shop manuals on CD. When the bushings arrived, I removed the arms and was surprised at how they were made. They looked very weak. I thought about just boxing in the arms with some metal stock, but ended up making my own arms with rob end bearings and DOM steel. I wanted the arms to use the same mounting points and stock hardware were possible. With the stock bolts being 14mm, I needed 14mm rod ends. These are not as easy to find as I thought, and they only come in one thread size, 14mm x 2.0. After finding a place that sold right and left hand taps, I purchased the taps and 8 of each rod ends.
Initially, I was only going to make the lateral arms, but I ended up making all six arms for the rear suspension. The trailing arm mounting point on the spindle required some machine work to remove the mounting stud and drill a new hole to mount the arm. The new mounting hole was made to hold a 14mm bolt and use the same size rod ends as the lateral arms. The first set I made was sold to a fellow GTXer that was closer to getting his car on the road and was going to be the test case. As far as I know, they never made it on the car and we lost contact. I had to start a second set. The second set is what's on my car now, and have a few design changes from the original. Instead of welding on a nut for adjustment, a flat was machined on either side of the arm to use a 19mm wrench to hold the arm during adjustments. With the use of left and right hand rod ends, the arms can be adjusted without removing them from the car. The sway bar mount will also be redesigned to pull from the center of the arm, preventing the sway bar from twisting the arm. This work will be done with all the part mounted on the vehicle and setting on the ground.
If you're interested in making a set of arms for your own GTX, you'll need the following: 14.0mm x 2 taps (left and right hand threads), 6 right and 6 left hand 14.0mm x 2 spherical rod ends and jamb nuts, 7/8" x .188 wall DOM mild steel cut to (4) 13" and (2) 21" lengths. You can save yourself the cost of a tap by only using right-hand threads, but the arms would need to be removed in order to adjust the length. If you don't want to purchase the taps, I can also provide you with just the arms, cut, tapped and ready to go. You would just need to buy the correct rod ends and possible modify your rear sway bar link end to work with the mount on the new arm. Feel free to contact me for more information on these arms.
Installation
Coming soon
