BFG Lifesaver Radial #48
Standard GM front suspension pieces with special Greenwood A-Arm bushings and roller bearing idler (steering) arm bushings
Front end springs would be changed according to the track. At Daytona they would use up to 1100 lbs.
Double-adjustable KONI shocks
The trailing arms were notched to help clear the 10 inch rims.
Rear frame was sectioned to permit the wider wheels to clear the chassis
Brakes were generally the GM J-56 calipers; used two locating pin holes for the pads. Also, another little trick of the time was to put in a spacer between the two caliper halves to permit the use of thicker pads.
Brake pads with ceramic backings were used to reduce heat transfer to the brakes
Wheel rims would be 8 inch in front and 10 inch in the rear, sometimes 10 inch all around
Greenwood manufactured molds (both front and rear) with the L-88 flares incorporated; these allowed up to 3 inches wider wheels over stock
The roll cages did not extend forward of the firewall; they were triangulated over the rear suspension; Greenwood may not have used the cross-brace between the two front suspension towers
Some subsequent racers have added side impact bars as part of the roll cage, as this is permitted by the SVRA and HRS as a safety measure
Wheels were 10 x 15 Minilites; a large stock of Minilites were purchased by Greenwood from the Penske Javelin program. The four-bolt wheels had to have the stud holes freeze-filled with similar material and then be remachined
Greenwood used very large wheel studs on all his cars. The holes in the wheels had to be drilled out to accommodate the studs
1972 tires were 60 series BFG Lifesaver Radial T/A 255/60-15; in 1973 the cars used the newer 60 series 245/50-15 front and 265/50-15 rear.
On the front wheels, Greenwood ran a very early version of the air extractor fans -- he used cut-down Corvair fans bolted onto the wheel to help move air across the brake area.
Body modifications to permit night racing included the recessed headlight brackets (dual light receivers) and marker lights to illuminate the car numbers for the scoring personnel
Because the three cars were designed to be running simultaneously, the Greenwood team also added two colored lights to the roof panels to help the pit crew identify which car was coming in; lights on the #48 car were red and orange and were located on the passenger side; lights on #50 were both orange and were also located on the passenger side; the #49 car had two red marker lights on the driver side
Hardtops were also a Greenwood mold to lighten the car; by 1974 the tops were just a lightweight shell with a Plexiglas backlight; they were just there to cover the roll cage
Open side pipes
Greenwood ran primarily all-aluminum ZL-1 engines for the BFG program. He bought these engines and rebuilt them himself as he felt his version was stronger and more reliable than the GM engine. NOTE: other cars of the era ran the steel block L-88 or L-89 engines as they were convinced that the aluminum blocks were not holding up) Some of the Greenwood engines would produce as much as 780 HP at 6200 RPM.
Originally wet-sump engines with Harrison oil cooler; later races did see dry-sump system used
M-22 transmissions; Borg-Warner T-10 viable alternate could have been used from time to time
12 specially molded interior pieces to make access to various parts easier than with the stock floor pan
Gauges and switches specific to racing; Greenwood installed his trademark large oil pressure gauges in a dominant position on the dash. The gauge was by American Gauge Company
Aftermarket driver's seat
Standard GM differential with tightened positraction clutches
Ring and pinion gears vary by track but generally used between 3.70:1 and 3.08:1 (even down to 2.98:1 for Daytona)
Standard big block alloy radiator with air ducting to service Harrison oil cooler
Special quick release center mounting bracket for top of radiator
Roll cage has multiple reinforcements in rear compartment meeting at a point behind the driver's seat; cage does not extend forward of firewall.
Chassis reinforcement in rear under the floor