'79/'80 Strut Swap & Brake Caliper Upgrade
   by Bruce Crawford
   crawford@planet.earthcom.net

[This article describes the process of swapping out your '79/'80 struts for later first gen hardware, and your '79 brake calipers for '80 calipers. This will give you the ability to use adjustable front strut cartridges and a much better brake caliper design. -RR]

   For the few of you guys that wanted this, here it is. It's simple, easy and worth the trouble if you like to go around corners and slow down on occasion. It's a good time to replace those spent wheel bearings, the potato chip rotors and put those stainless lines on. There's a couple special tools needed. E-mail me if you need more specifics.

   '79 and '80 RX-7 owners who want/need adjustable strut cartridges need to swap to the '81-'85 struts. I suggest '79 owners upgrade to the '80 calipers (only) as the '79 calipers are the wedge variety and, quite frankly, suck. You can use the wedge brakes if you must. Don't get '81-'84 calipers as the hose threading is different. The '80-'85 caliper hangers are all the same. All of the brake caliper hangers, spring perches, upper bearing mounts, ball joint points, etc., are totally interchangeable. It's important to note that the '84-'85 rotors and outer wheel bearings are different, but the entire rotor/hub/bearing assemblies are interchangeable as an assembly.

   Source a set of '81 and later strut assemblies (most junkyards will not sell just housings), so make sure the upper bearing and spindle are in good shape (not to mention the rotor, wheel bearings). Try to get the year of the car they were removed from so you know what rotor/wheel bearing you have. Give the calipers (not the hangers) to a later RX-7 owner. He'll be grateful. The entire process is a 100% bolt up swap. The only part you need is the actual strut tube (has spindle and brake line mount attached). You are essentially swapping all your hub/rotor, caliper, wheel bearings, spring, spring perch, boot, bumper, and upper strut mount to the newer part. In the process, you will need the later strut cartridge, and new grease seals. Special tools required: a spring compressor (by gosh, be careful with that thing), and a tie rod end remover.

Follow this to remove struts:

   Jack car up and support with jackstands. Don't rely on the jack. Remove the brake line clips, caliper, tie rod end, four bolts that retain the backing plate/caliper hanger assembly, two ball joint bolts, and the wheel bearing retainer nut and remove the entire hub/rotor/wheel bearing assembly. Unbolt the four upper bearing mounts from the strut tower. Before you drop the struts, make a mark on the strut tower which way the little arrow on the upper mount points. Be careful removing the last nut as the strut assembly will fall away.

   Compress spring with a spring compressor until the assembly goes slack. Remove nut from strut cartridge shaft and remove upper bearing. Remove the spring perch, compressed spring, bumper and boot from the shaft. What you have left is a strut tube with a nasty "wet" strut cartridge inside. Throw it in the neighbors' yard and forget you ever had it. For those of you upgrading the calipers, throw those and the early hangers, too. Repeat the disassembly process with the newer assembly, except don't throw the strut away. Put in that Illumina cartridge and fill with light oil. Torque the retainer nut. Put the bumper and the boot on the shaft, followed by the compressed spring, the spring perch, and the upper bearing. Tighten the upper bearing nut to proper torque. Release the compression on the spring.

   Place strut back into car first with the four upper nuts (don't tighten yet). Make sure you orient the arrow to your mark on the strut tower. Tighten the ball joint bolts first. Replace the grease seal on the back of the hub (don't reuse the old one unless you like grease on your rotors. Repack the wheel bearings while you're in there. Replace the backing plate, hub. Replace the caliper. Replace the brake line clips. Replace the tie rod end (use new cotter pin). Be careful not to kink brake line. Tighten upper bearing nuts. Remove jack stands, drop jack. Get an alignment.

   Now you've got decent brakes and adjustable shocks.