Spec 87-88 Porsche 944 S 2.5L / 89-91 944 S2 3.0L Steel Flywheel
The SPEC SP31S is a steel flywheel for the 16-valve Porsche 944: the 1987-1988 944 S with the 2.5L engine and the 1989-1991 944 S2 with the 3.0L. Owners usually come looking for it during a clutch job, when the old flywheel turns out to be heat checked, worn past a safe resurface, or simply tired after decades of use, and they want a fresh, lighter part instead of hunting for a used one.
The 944 puts its transaxle at the rear and the clutch at the engine, joined by a central torque tube. The flywheel bolts to the crankshaft at the back of the engine, carries the starter ring gear and gives the clutch disc its rear friction face. Because the clutch sits up front while the gearbox sits in the back, getting to the flywheel means dropping the transaxle and sliding the torque tube rearward, so this is not a job anyone wants to do twice.
SPEC catalogs the SP31S in its steel flywheel line and lists it at 13 lb. Steel tolerates heat and repeated resurfacing well, which makes it a sensible pick for a car that sees both road and track time. A lighter flywheel lets the engine spin up and slow down faster, so expect crisper throttle response and easier heel-toe downshifts, with a little more attention needed on takeoff.
Once the clutch is apart, inspect the face for cracks and flatness and check the ring gear. A glazed but sound flywheel can be resurfaced; a cracked one must be replaced. Our resurface vs. replace page covers the decision, and lightweight vs. stock flywheel explains the drivability trade-off. If you are chasing slip, rule out hydraulics and a worn disc first using our slipping diagnosis guide and clutch chatter causes.
SPEC lists SP31S for the Porsche 944 S (1987-1988) and 944 S2 (1989-1991). Our listing data names the 944 S; the S2 years come from SPEC's catalog. It is not listed for the 8-valve 944, the 944 Turbo or the 968. Since many of these cars are now 35 years old and some have had engine or clutch changes, match the crank and clutch to the original application, or send us the year and VIN and we will confirm. More flywheels are on our hard parts page.
| Brand | SPEC |
| Part number | SP31S |
| Fits | Spec 87-88 Porsche 944 S 2.5L / 89-91 944 S2 3.0L Steel Flywheel |
| Vehicle fitment | Porsche 944 S (1987-1988) |
| Type | Flywheels |
| Condition | New |
| Ships | Same business day (in stock), from the USA |
| Warranty | 1-year |
Yes. SPEC lists it for the 1987-1988 944 S and the 1989-1991 944 S2.
SPEC does not list it for those cars. It is cataloged for the 16-valve 944 S and S2 only.
SPEC lists the SP31S at 13 lb.
Steel handles heat well and takes repeated resurfacing, so it suits a car that sees track days as well as road miles.
Use a clutch SPEC lists for the 944 S and S2. The SP313F Stage 3+ and SP311 Stage 1 clutches are both cataloged for these cars.
Yes. The clutch and flywheel sit at the engine, so the transaxle comes out and the torque tube slides back to reach them.
