SuperPro KIT130K Review: 1993-1995 Mazda RX-7 FD Guide

If you own a 1993–1995 Mazda RX-7 (FD3S), your suspension bushings are almost certainly 31 to 33 years old — and physics has not been kind to them. The single highest-impact chassis investment you can make in 2026 is a proper polyurethane RX-7 FD bushing kit, and the SuperPro KIT130K Master Bushing Kit is the package the FD community keeps coming back to. In this guide we break down exactly what's in the kit, how it compares to OEM rubber and harder polyurethane brands, the one critical part it does not include, and the complementary chassis-refresh upgrades that turn a stock 13B-REW car back into the surgical scalpel Mazda originally shipped.

Why Your FD3S Needs New Bushings in 2026

The newest FD3S rolled off the Hiroshima line in 1995. Even the youngest examples are now over 30 years old, and rubber suspension bushings simply do not survive that long — especially under the engine bay of a twin-turbo rotary that runs notoriously hot. The OEM rubber has oxidized, cracked, and in many cars has had its inner bond completely fail. The result is a chassis that feels tired even on a freshly-rebuilt 13B-REW.

Here are the symptoms FD owners report most often before a bushing refresh:

• Rear-end clunk on start/stop — worn pillow ball bushings in the rear upper and lower control arms and toe links.
• Wheel hop on hard launch — failed differential-to-subframe bushings letting the diff cage move.
• Clunk on shift — same root cause as wheel hop (diff mount slop).
• Vague steering with a knock on turn-in — steering rack mount bushings have lost compression.
• Mid-corner "push" understeer after a clunk — slop in the toe-control-arm bushings is allowing dynamic toe change under load.
• Visible play at the tire — more than about 1/8 inch of rotation at the outer tire face with the wheels lifted means excess bushing slop.

In our Tampa shop, we see two FD chassis types pull onto the lift: cars that have had their bushings done, and cars that need it done yesterday. There is no in-between.

Inside the SuperPro KIT130K Master Bushing Kit

SuperPro's KIT130K is the "Standard Alignment" Front + Rear Vehicle Enhancement Kit for the FD3S. It is the most complete single-box bushing solution available for the 93–95 RX-7, containing 28 bushings, 22 inner tubes, and 2 outer shells. The "Standard Alignment" label means it preserves factory geometry — you replace worn rubber with poly that puts the suspension links back where Mazda designed them. The adjustable variant (KIT130ADJK) adds camber and caster correction but drops two pieces (the rear upper-control-arm inner bushing and the rear shock lower bushing) in exchange for the alignment hardware.

Verified contents of the standard KIT130K:

• Front control arm bushings (front + rear positions)
• Front sway bar mount and end-link bushings
• Steering rack & pinion mount bushings
• Differential to cross-member mount bushings
• Rear trailing arm bushings
• Rear toe-control arm bushings
• Rear upper control arm inner bushing (exclusive to KIT130K)
• Rear shock absorber lower bushings (exclusive to KIT130K)
• Rear sway bar mount and end-link bushings

SuperPro vs OEM Rubber vs Energy Suspension: How Do FD Bushings Compare?

There are three realistic paths for a 2026 FD3S bushing refresh: chase down OEM rubber, install softer street polyurethane (SuperPro or Powerflex), or commit to harder track-grade polyurethane (Energy Suspension, Prothane). Here is how those choices actually feel on the road.

The takeaway: SuperPro's 70A durometer is the FD community's quiet consensus for a street car. It is softer (and quieter) than Energy Suspension or Prothane, but firm enough to eliminate the slop a brand-new OEM rubber bushing creates on day one. For a dedicated track FD with a roll cage and the owner's permission slip on body movement, harder poly or even spherical bearings make sense — but for a 95% of the time street car, KIT130K is the durometer Goldilocks would buy.

The One Critical Part KIT130K Does NOT Include

This is the single most-overlooked detail in every other RX-7 bushing guide: the SuperPro KIT130K does not contain the six rear pillow balls. Two pillow balls live in each rear lower control arm, plus one in each rear upper control arm — six total. They are spherical bearings (not bushings), they have a unique part topology, and they are the single biggest source of the rear clunk that drives most FD owners to do this job in the first place.

Source the pillow balls separately from OEM Mazda (genuine part) or J-Auto (Japanese OE supplier). Budget roughly $200–$350 depending on the source. Installing KIT130K without refreshing the pillow balls is the most common reason owners report "the clunk is still there." Do them both at the same time — the suspension only comes apart once.

Complementary FD3S Refresh: The Parts To Do While the Suspension Is Apart

The suspension only comes off the car once, so smart FD builders queue up adjacent jobs while everything is accessible. The shortlist below is built from the same NLP Performance catalog and covers the four most common "while-I'm-in-there" upgrades on a 13B-REW chassis refresh: braking, cooling, drivetrain, and exhaust.

Brakes: DBA 4000 Slotted Rotors + Hawk HPS Pads

The factory rotors on a 30-year-old FD are usually scored, lipped, or warped, and the calipers come off anyway when you pull the front knuckles. DBA's 4000 series rotors use high-carbon alloyed iron with their Kangaroo Paw vane design (144 diamond/teardrop cooling pillars) for roughly 30% more cooling surface area and 20% better cooling efficiency than a straight-vane rotor. The T3 tri-symmetrical slots vent pad gas and dust for cleaner pedal feel.

Pair the DBA rotors with Hawk's HPS street pads — their Ferro-Carbon compound delivers a claimed 20–40% more stopping power over OEM with low dust, minimal noise, and gentle rotor wear. The HPS is the "right" street pad for a daily FD; step up to HP+ if you're doing track days. If you'd rather buy the whole front brake corner in one box, the Power Stop Z23 Evolution Sport kit bundles drilled-and-slotted zinc-plated rotors with carbon-fiber-ceramic Z23 pads and stainless hardware — ideal for an owner who wants one part number to solve the front brakes ($193.74) and a matching rear Z23 kit ($174.85) on the back axle.

Cooling: Mishimoto 68°C Racing Thermostat

The 13B-REW is famously heat-sensitive. OEM thermostat opens at 82°C (180°F); Mishimoto's racing thermostat opens 14°C earlier at 68°C (154°F), starting coolant flow sooner and pulling the operating window down. Apex seal failures and detonation events both correlate strongly with elevated coolant temps on a twin-turbo rotary, and this is one of the single cheapest insurance upgrades on the platform. Install it while the front of the engine is accessible.

Drivetrain: Exedy Hyper Series Clutch Refresh Kit

If the transmission ever comes out for a clutch job, the Exedy Hyper Series Accessory Kit (release bearing, pilot bearing, alignment tool) at $102.58 is the bolt-on glue for the rest of the Hyper Single or Hyper Twin kits the FD community runs. Exedy's Hyper Single handles 400–500 hp; the Hyper Twin handles 600–700 hp and around 500 ft-lb at the flywheel — both significantly upstream of what stock 13B-REW puts down, with headroom for a 4-puck single-disc or a multi-disc setup. Cerametallic T5001 friction, chromoly lightweight flywheel, purple-anodized forged-aluminum cover.

Exhaust + Ignition: HKS Turbo Hi-Power + NGK Plug Wires

If the rear suspension is on the bench, the exhaust hangers are right there. HKS's Turbo Hi-Power cat-back for the FD uses SUS304 stainless steel built around the straightest possible exhaust path — minimal bends keep gas velocity high, which the sequential twin-turbo setup loves for mid-range boost response. Sound is unmistakably rotary and aggressive at full throttle; the inner silencer keeps it civil at cruise. Pair with a fresh NGK spark plug wire set ($30.57) — NGK's fiberglass-stranded core has half the resistance of typical carbon-core wires, and on a 13B-REW (four plugs, leading and trailing) a single misfire fast-tracks apex seal damage. Both are cheap insurance.

Gauge Cluster: AutoMeter A-Pillar Dual Pod

Boost and EGT (or boost and oil pressure) are non-negotiable on a 30-year-old twin-turbo rotary. AutoMeter's A-pillar dual gauge mount (part 22674, $99.72) is purpose-fitted to the 92–02 FD with OEM-grade tolerances and paintable composite construction. The gauges sit at proper driver-eye angle without obstructing the windshield — the same view Mazda engineers gave the factory tachometer.

Installation Tips for the FD3S Master Bushing Kit

Here's what you actually need to know before you start unbolting things:

• You will need a hydraulic press. Period. Removing 30+ year old OEM rubber bushings is the labor sink — not pressing in the SuperPros. Bring the loose arms to a press shop if you don't own one.
• Trim the OEM rubber lips with a utility knife before pressing — this saves the bushing tube and makes the press job dramatically easier.
• Use only silicone or PTFE-based grease. SuperPro ships their own with the kit. Lithium-based or petroleum-based greases will destroy polyurethane. Apply liberally to inner sleeves and bushing flanges.
• Budget a full weekend minimum for a first-timer DIY. Shop labor typically runs 8–12 hours depending on hardware condition.
• Order the six rear pillow balls in the same parts list. KIT130K does not include them and the suspension only comes apart once.
• Schedule a four-wheel alignment on the same day the car comes off the lift. Every link's rest position changes — alignment is not optional.
• Re-grease every five years with silicone grease. Squeak is the warning sign that grease has migrated out.