The X180R story runs through three closely related machines built on the same Esprit foundation, and the temptation is to treat them as one car in three states of tune. In reality they were distinct specifications with distinct purposes. The matrix below sets them side by side: the Type 105 SCCA World Challenge race car of 1990, the twenty road-legal X180R homologation cars of 1991, and the more thoroughly developed Type 106 IMSA Supercar racer that followed. Where the factory record is silent or a figure could not be independently verified, the cell is marked “—” rather than filled with a guess. A weighted cell marks where the three variants genuinely diverge on the same fact.
| Esprit SE (SCCA Race Car) | X180R (Homologation Car) | X180R (IMSA Race Car) | |
|---|---|---|---|
| 01Overview | |||
| Purpose | SCCA Race Car | Homologation Street Car | IMSA Race Car |
| Model | Type 105 | Type 105 | Type 106 |
| Model Year | 1990 | 1991 | 1991+ |
| Production Count | 2 | 20 | 3 (+ 2 converted Type 105 SCCA race cars) |
| 02Engine | |||
| Engine | Type 910S inline-four | Type 910S inline-four | Type 910S inline-four |
| Turbocharger | Garrett AiResearch T3 | Garrett AiResearch T3 | Garrett AiResearch T3 |
| Intercooler | Lotus Chargecooler | Lotus Chargecooler | Lotus Chargecooler |
| Head | Aluminum alloy | Aluminum alloy | Aluminum alloy |
| Maximum Boost | — | 1 bar (14.5 psi) | — |
| Engine Capacity | 2,174 cc | 2,174 cc | 2,174 cc |
| Horsepower | 285 hp | 285 hp | 300 hp |
| Fuel Injection | Lotus Carlton/Omega | Lotus Carlton/Omega | Lotus Carlton/Omega |
| 03Drivetrain | |||
| Transmission | Blueprinted by Renault | Renault 5-speed, strengthened competition casing, limited-slip differential | Renault 5-speed, strengthened competition casing, limited-slip differential |
| 04Chassis & Body | |||
| Chassis | Ungalvanized steel backbone, front cross member, tublar engine bay | Same as SCCA Type 105 (except galvanized) | Same as SCCA Type 105 |
| Body | Light fiberglass (GRP) shell | Light fiberglass (GRP) shell | Light fiberglass (GRP) shell |
| Roll Cage | Fully integrated, RAC approved | Fully integrated, RAC approved | Fully integrated, FIA approved/strengthened |
| Side & Rear windows | Plastic (Lexan?) | Production glass | Plastic (Lexan?) |
| 05Suspension & Brakes | |||
| Front Suspension | Uprated and strengtheneed, adjustable revised geometry & lowered | Same as SCCA Type 105 | Racing adjustable |
| Rear Suspension | Upgrated, strengthened, provision for rear anti-roll bar and lowered | Same as SCCA Type 105 | Racing adjustable |
| Brakes F/R | 13"/12" AP Racing brake discs, 4-piston alloy calipers | 13"/11" AP Racing ventilated discs, 4-piston calipers | 13"/11" AP Racing ventilated discs, 4-piston calipers |
| 06Wheels & Tires | |||
| Wheels | 16" × 8½ (front), 16" × 9½ (rear) | Revolution 3-piece aluminum/magnesium center alloy wheels, 16" × 8½ (front), 16" × 9½ (rear) | Revolution 3-piece aluminum/magnesium center wheels, 16" × 8 (front); 17" × 10½ (rear) |
| Wheel Offsets | — | — | — |
| Tires | Goodyear Eagle ZR | Goodyear Eagle ZR 225/45×16 + 255/50×16 | Goodyear Eagle ZR 245/45×16 + 315/40×17 |
| 07Dimensions | |||
| Length | 168" | 168" | 168" |
| Width | 75" | 75" | 75" |
| Height | 43" | 43" | 43" |
| Wheelbase | 96" | 96" | 96" |
| Track | 60½" (front) / 62" (rear) | 60½" (front) / 62" (rear) | — |
| 08Weight | |||
| Weight | Race weight: 2,400 approx. | 2,280 lbs | Race weight: 2,500–2,800 lbs * |
The IMSA Type 106 minimum race weight had a model-specific base weight set by IMSA Bridgestone Supercar rules, steadily increasing each year based on overall success. On top of that, the success of each individual chassis dictated additional per-race penalty weight for that car. The minimum weight included the weight of the driver. In an article, Jack Ansley stated they were able to get the X180R down under 2,000 lbs without any driver and weight penalty additions.