The Elise is so superb, it makes you overlook the fact that it has a peaky, fragile 2ZZ Toyota engine. This Lotus made it into USCC as a last-minute call up, because our original selection, running a turbocharged 2ZZ, encountered "difficulties".
When we contacted Joe McCarthy of Prototype Racing and explained our desire to have a blown mid-engined roadster of British/Japanese descent attend our party, he graciously agreed to bring his Lotus. Joe, you see, designed a conversion kit to install the Honda K-series engines into the Elise/Exige chassis.
There was only one problem, we called him six days before the competition. And the supercharger system he was fabricating for his K20A-powered Elise was sitting on the workbench. In spite of our untimely invite and the enormous amount of work needed, Joe promised to make it.
As you know, the K20 is good, far superior in every regard to the 2ZZ, and a supercharged and intercooled K20 is even better. Based around a Roots-type Eaton M62 blower, Joe's kit uses a compact and highly efficient air-to-water intercooler. Look out for a setup derived from this design offered by Jackson Racing.
The M62 squeezes 9psi of boost through a JDM K20A - stock from oil pan to valve cover. The blown K20A breathes through a Prototype Racing velocity stack intake and TIG-welded stainless exhaust manifold. Increased fuel demands are met by a Walbro 255lph fuel pump and stock Honda injectors modified to flow at 520cc/min.
Tuned using a Hondata K-Pro ECU, an earlier version of the Prototype Racing Elise made 320 wheel-hp and 210lb-ft of torque, about twice as much power as the Toyota 2ZZ, with much, much more meat under the curve. The torque figure may seem low from a Roots-type blower, but this makes for a car both easy on parts and linear in power delivery, which should pay big on the road course.
There exists a point where fabrication transcends craft and becomes art, via rarified material, provident design and meticulous execution. The parts from Prototype Racing should woo engineering judges, even if the fact that the Elise houses one of the best four-cylinders in the world might not.
After sufficiently motivating the Elise, Joe addressed his one other gripe with the stock model: the dampers. After losing several fillings on a trip down the 405 freeway, owing to the stocker's stiff compression damping, Joe went ultra-top shelf and had a custom set of Ohlins TT44 triple-adjustable, remote-reservoir coilovers made. These have the same part number as those used on the Audis that enjoy winning the 24 Hours of Le Mans every year. Despite specifying a spring rate about twice as hefty as stock, Joe reports that the car rides significantly better, with an overall enhancement of its already nutty lateral prowess. They also cost Joe more than the sum of every aftermarket suspension part ever purchased in a long and storied automotive career.
That much motor in a sprightly Elise can generate speeds on the straights that are outside the design parameter of the supplied brake parts, so Joe swapped in a set of Ferodo DS3000 brake pads on each corner.
Lucky Joe is also the owner of a track beast Exige, from which he harvested more comfortable and supportive driver and passenger seats. Elsewhere, the Elise is untouched. An almost-stock Ferrari won the USCC (in 2001) by being good everywhere and inoffensive where it counts. This Elise is a near-perfect driving tool with more engine and better footwork, making it eminently more driveable, and, by extension, a contender for ultimate street and track car. It just remains to be seen whether this little gem will charm its way into the winner's circle.
Editor's Note: With its mid-engine layout, Lotus handling and Honda power, you could call this an F1 streetcar. An earlier supercharged version was seen lapping Buttonwillow a full two seconds faster than last year's winner - before it blew up. -EL
Prototype racing 2006 lotus eliseEngine
Engine code: JDM K20A
Type: 1998cc in-line four, aluminum block and head, supercharged and intercooled
External mods: Prototype Racing K20 conversion kit, Jackson Racing/Prototype Racing intercooled Roots-type supercharger, 2.25x3.5x7-in. water-to-air intercooler, exhaust manifold and velocity stack intake pipe, K&N RF1043 air filterEngine management mods: Hondata K-Pro ECU, Walbro 255lph fuel pump, modified 520cc stock injectors
Layout: Transverse mid engine, rear-wheel drive
Drivetrain mods: Factory Type-R Torsen-type LSD, Prototype Racing axles
Front: Custom Ohlins TT44 three-way adj. coilovers w/remote reservoirs and 325 lb/in springs, PrototypeRacing billet tops
Rear: Custom Ohlins TT44 three-way adj. coilovers w/remote reservoirs and 475 lb/in springs
Front: Ferodo DS3000 brake padsRear: Ferodo DS3000 brake pads
Wheels: 16x5.5 (f), 17x7.5 (r)Tires: 175/55R16 (f), 225/45R17 (r)Yokohama Advan A048(M)
Lotus Exige seats