Competition Clutch 1994-2005 Mazda Miata 11lb Steel Flywheel
The Competition Clutch 2-746-STU is the ultra-light steel flywheel for the 1.8-liter Mazda Miata, covering the NA and NB roadsters from 1994 through 2005. It is the part autocross, track and turbo Miata owners look for when they want the BP engine to snap onto throttle and fall back quickly for heel-toe downshifts, or when a clutch job shows a glazed, cracked or worn factory flywheel. Our listing title rounds it to 11 lb; Competition Clutch lists the actual weight as 10.30 lb.
The flywheel bolts to the back of the BP crank and does three jobs: it carries the starter ring gear, it gives the clutch disc its rear friction face, and its mass carries the four-cylinder through its firing pulses at idle and low rpm. The small 1.8 makes modest torque, so every pound of rotating mass is felt in how quickly it gains revs. CC machines the 2-746-STU from 4140 forged chromoly as one piece, so there is no separate ring gear to work loose.
The STU suffix is what separates this part from its sibling. CC builds STU flywheels with less material for forced-induction, track and rally cars and recommends them with Stage 3 and up clutches. The street version, the 2-746-ST at 13.00 lb, is the one CC aims at naturally aspirated daily drivers with Gravity, Stage 1 and Stage 2 kits. Pick the STU if the car sees boost or time on track; pick the ST if it mostly commutes. Our lightweight vs. stock flywheel guide covers the trade-off.
Rule out the hydraulics first: an aging slave or master cylinder that will not fully release feels like slip or hard shifting. Our slipping diagnosis guide and flare vs. slip explainer help pin down the cause, and the Miata manual transmission guide covers gearbox faults that mimic clutch trouble. With the transmission out, check the face for cracks and wear; if it is cracked or already machined, replace it rather than cutting it again (see resurface vs. replace).
Competition Clutch lists the 2-746-STU for 1994-2005 Mazda Miata with the 1.8L engine, NA and NB chassis. It does not cover the 1990-1993 1.6L cars, and it does not fit the 2006-up NC or later cars. The 2004-2005 Mazdaspeed MX-5 used upgraded six-speed transmission and clutch assemblies, so Mazdaspeed owners should send us their VIN before ordering. Manual transmission only. More flywheels and clutch parts are in our hard parts category.
At 10.3 lb the idle drops faster and launches need more care than stock. That is the point of the STU, and it rewards a driver who keeps the revs up.
| Brand | Competition Clutch |
| Part number | 2-746-STU |
| Fits | Competition Clutch 1994-2005 Mazda Miata 11lb Steel Flywheel |
| Vehicle fitment | Mazda Miata 11Lb Steel (1994-2005) |
| Type | Flywheels |
| Condition | New |
| Ships | Same business day (in stock), from the USA |
| Warranty | 1-year |
Competition Clutch lists the 2-746-STU at 10.30 lb. Our listing title rounds it to 11 lb.
No. CC lists it for the 1994-2005 1.8L Miata only. The early 1.6L cars need a different flywheel.
The STU is the ultra-light 10.3 lb version CC recommends for turbo, track and rally cars with Stage 3 and up clutches. The 2-746-ST is 13.00 lb and aimed at street cars with Gravity, Stage 1 and Stage 2 kits.
CC lists 1994-2005 1.8L NA and NB cars, and the Mazdaspeed uses a 1.8L, but it came with an upgraded six-speed and clutch. Send us the VIN and the clutch you plan to run before ordering.
No. This is the flywheel only. Pair it with a clutch kit rated for your power; CC recommends Stage 3 and up with STU flywheels.
Competition Clutch says to shift as often as possible during the first 500 miles so the disc material beds into the flywheel and pressure plate.
