Product Details
The Riaction TPU Coilovers for the 1987-1991 Porsche 944 (Late model) 87-91 (NA) 86-91 (Turbo) LATE/MODEL bring Riaction's digressive damper technology to the Porsche 944 (Late model) 87-91 (NA) 86-91 (Turbo), engineered for drivers who prioritize high-speed control, flatter cornering, and sharper response than a linear coilover can deliver. Each TPU set is built-to-order so valving and spring selection are matched to your exact Porsche 944 (Late model) 87-91 (NA) 86-91 (Turbo) application, with the same 32-level damping adjustment and full-length ride-height range you'd expect from the Riaction platform. For LATE owners chasing a track-focused setup without giving up street composure, this LATE coilover kit bridges the gap between daily driver and weekend warrior.
Digressive pistons give the TPU a higher initial damping rate at low shaft speeds (body roll, weight transfer) and relax over big inputs (potholes, curb strikes), so you get better control without the harshness of a stiffer linear tune. Riaction coilovers for the 1987-1991 Porsche 944 (Late model) 87-91 (NA) 86-91 (Turbo) ship fully rebuildable and backed by a 2-year warranty, making the TPU a long-term investment for enthusiasts serious about their 944 (Late model) 87-91 (NA) 86-91 (Turbo) setup.
TPU Series Technology
- Digressive piston design — high control at low shaft speeds, compliant over big hits
- 32-level damping adjustment (1-Way)
- Monotube damper with seamless 52mm electroplated carbon steel body
- 44mm CNC-machined 6061 aluminum piston
- Built-to-order valving matched to vehicle and spring rate
- SAE9254 cold-wound linear main springs
- Multi-thickness valving shims for precise damper tuning
- Polyurethane oil seals and 7.5W suspension fluid
- Fully rebuildable — built to be serviced, not replaced
Features
- Full-length ride-height adjustment (preload-independent)
- 32 levels of damping adjustment
- Digressive valving for better control under load
- Optional Swift Springs upgrade (sold separately)
- Built-to-order — 2-4 week lead time typical
- 2-year limited warranty
TPU vs GT1 — Which Is Right for You?
Both kits share the same 52mm monotube damper body, 32 levels of damping, full-length ride-height adjustment, and spring rates. The difference is in how the damper reacts:
| Riaction GT1 | Riaction TPU | |
| Damper valving | Linear piston | Digressive piston |
| Low-speed control (body roll, turn-in, weight transfer) |
Good | Sharper — higher initial resistance |
| Big-impact compliance (potholes, curbs, expansion joints) |
Follows damping curve | Softens — blow-off relieves harshness |
| Best for | Street, canyon, occasional track | Track-focused, autocross, aggressive street |
| Build | In stock | Built-to-order (2–4 weeks) |
Short version: choose GT1 if you want the best daily-street-track balance and ship-ready. Choose TPU if you want tighter response under load and don't mind the lead time for a digressive tune.
Specifications
| Part Number | PS-016-ST-TPU |
| Part Name | Riaction TPU Coilovers |
| Vehicle | 1987-1991 Porsche 944 (Late model) 87-91 (NA) 86-91 (Turbo) |
| Chassis Code | LATE/MODEL |
| Adjustment Type | 1-Way |
| Damper Valving | Digressive |
| Ride-Height Adjustable | Yes |
| Spring Rate - Front | 6 Kg/mm |
| Spring Rate - Rear | 12 Kg/mm |
| Top Mounts - Front | Pillowball |
| Top Mounts - Rear | Pillowball |
| Camber Plates - Front | No |
| Camber Plates - Rear | No |
| Suspension Design - Front | True Coilover |
| Suspension Design - Rear | |
| Built-to-Order | Yes |
| Notes | LOW VERSION |
Vehicle Fitment
- 1987 Porsche 944 (Late model) 87-91 (NA) 86-91 (Turbo) (LATE/MODEL)
- 1988 Porsche 944 (Late model) 87-91 (NA) 86-91 (Turbo) (LATE/MODEL)
- 1989 Porsche 944 (Late model) 87-91 (NA) 86-91 (Turbo) (LATE/MODEL)
- 1990 Porsche 944 (Late model) 87-91 (NA) 86-91 (Turbo) (LATE/MODEL)
- 1991 Porsche 944 (Late model) 87-91 (NA) 86-91 (Turbo) (LATE/MODEL)