corr Pro Lite Nissan Frontier - engine - Photo 9132728

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After unbolting the passenger-side V-bar in the windshield area (or more correctly, a "front opening" since CORR trucks don't use windshields), the motor can be extracted. The 2.5-liter's block and cylinder head are production items massaged to produce competition-level horsepower.

To illustrate the differences between the Frontier on your local Nissan dealer's lot and the one Casey campaigns in CORR...

Ray and Casey Currie turned a few dozen Dzus quick-release tabs.

Stripped of its skins, the hardcore nature of Casey's truck is readily apparent. Like its bigger Pro 2 brother, Pro Lite trucks are built based on spec drawings available from CORR. Pro 4 is the only CORR class that doesn't confine builders to a specific blueprint.

After unbolting the passenger-side V-bar in the windshield area (or more correctly, a "front opening" since CORR trucks don't use windshields), the motor can be extracted. The 2.5-liter's block and cylinder head are production items massaged to produce competition-level horsepower.

Mounting location and position for the Electromotive ignition control box turned out to be crucial, as the box failed when mounted vertically. Heat and vibration are the box's enemies. This horizontal mounting position, with its constant airflow and insulated rubber mounting studs, has proven to be the ticket.

It was no surprise to see a Currie 9-inch rearend in a Currie truck. The Pro Lite uses a Track 9 housing with chrome-moly axletubes. To ensure reliable weld quality and a jewel-like appearance, the housing and its attendant bracketry were fused together with expertly performed TIG welds.

A Currie full-float setup combines with 5/8-inch wheel studs and Wilwood disc brakes for durability, light weight, and race-level performance.

Inside the dropout centersection, you'll find a full spool intertwined with 35-spline axleshafts. Ring-and-pinion ratios vary between 4.56 and 5.29 depending on track location and track conditions. The tranny features additional gear reduction by using a 1.6:1 Fourth-gear ratio in place of the more conventional 1:1.

Textbook-quality TIG welds are everywhere on this chassis. Had the fiberglass skins stayed in place, we never would have been treated to this view.

This truck was originally run by CORR veteran Art Schmitt. As delivered to Casey, the Howe steering rack had a 2.8:1 ratio. "It drove me nuts. I had to turn the wheel like crazy around the corners," comments Casey. "When we asked Howe for a 1:1-ratio rack, they were kind of surprised. Howe had no trouble building the rack; they just hadn't been asked to use that ratio before." The new rack makes for ultraquick steering, and Casey can steer lock-to-lock with less than one full turn of the wheel.

The front suspension is also built to CORR specs. Travel is specified at no more than 12 inches. Camber gain can be adjusted as needed by repositioning the upper control arms in one of three available positions.

Rear suspension is specified at no more than 14 inches, so a single coilover mounted directly to the axle works just fine. The dual-rate springs seem to be stacked upside down, with the lighter coil on the bottom. Ray Currie explains: "When combined, these springs yield a rate of 100 pounds. As soon as the slider hits the stop, the upper spring is no longer active, and the lower spring has a rate of 140 pounds." A Speedway Engineering sway bar keeps body roll in check.

No codrivers here! The G-Force four-speed takes the place normally reserved for a passenger. That blue-knobbed lever activates the rear brakes only, which brings the nose down when activated mid-flight. Motocross racers also use this trick to control airborne attitude.