Saturday, January 08, 2022

from factory stock to lightweight street racer, there's a lot to be done to increase power and replace factory stock heavy parts with light weight stuff... in every system, and in every place possible... and these are very interesting to me


I have not had the chance, or possible situations that could occur, that would allow me to drive Corvettes, but I did have a part time job helping to restore 1969 Corvettes, and when I was a teen, I had an obsession with Vettes, because of their shape. I even subscriber to Corvette Fever magazine. Plus, I simply dig upgraded stock cars (like the Optima Challenge competitors)

So, when I came across this story, I wanted to learn what the owner did to this '68 to shed 500 pounds. 

He was a Pontiac mechanic, who went to the races and met and got to know GM's racing community like Bill Mitchell Vice President of Design, as well as Jerry Palmer – head of Chevy III design studio, and Dick Henderson, caretaker of GM concept cars.

Steel bumpers were removed, as were the steel bumper extensions and parking brake assembly. The heavy core support and radiator were removed and an L-88 aluminum radiator was mounted lower, for optimal airflow.

He deleted the windshield wiper system’s metal door, linkage, and vacuum actuator. The removable rear window and metal framework were replaced by a plexiglass piece, while the rear Astro ventilation ductwork was also removed, together with grilles, vacuum actuator, and door.

The headlights were inspired by the Lola Ford GT. The quad headlights sit behind plexiglass covers and are nested in 1963 Corvette headlight buckets. The turn signals came from a 1966 Pontiac GTO and the high beams were GE aircraft landing lights. GM did not offer sports mirrors at the time, so the original chrome one was removed and a pair of 1969 Mustang BOSS 302 mirrors were molded directly into the doors.

the interior was also simplified. It featured a radio and heater delete, and Richard fitted a factory radio block-off plate. The gauge cluster above it was simplified and the die-cast center console was replaced with a lightweight aluminum panel.

The veteran Pontiac technician used window switches that were 1969 Pontiac Station Wagon tailgate window switches. Those were recessed into the leather-padded part of the console. Aside from using a lot of aluminum, Richard also removed the factory sound deadening and carpet padding, after which he reinstalled the original carpeting directly over the fiberglass floor. The lightweight seats were sourced from Bruce Meyers, creator of Meyers Manx

The steering wheel came from a 1969 Pontiac Trans Am, which can be adjusted outwards and inwards by popping out the 1956 Corvette horn button and loosening a screw beneath it

The parts Richard used in order to assemble the 454 cubic-inch Big-Block V-8 are specially picked. The mighty 454 cubic-inch ZL-1 engine featured an all-aluminum block and heads with LS6 and LS7 internal parts, ZL-1 aluminum block, LS7 crankshaft, - LS-7 rods with 7/16” boronite bolts (LS-6 rods had 3/8” bolts), LS-6 pistons, 11.0-to-1 compression, aluminum heads (closed chamber to match the 11.0-to-1 LS-6 pistons), L-88 / ZL-1 / intake manifold with correct L-88 / ZL-1 carb from GM, L-88 / ZL-1 cowl induction with correct air cleaner and flame arrestor parts, LS-7 lightweight hollowed-out flywheel and clutch and harmonic balancer, ZL-1 aluminum water pump, 1967 L-88 road draft tube instead of pcv, cut and sleeved for rocker cover removal, GM transistor distributor curved to L-88 spec with MSD-6 box hidden inside dash, L-88 / ZL-1 red metallic core plug wires and cap, Crank, rods, pistons, flywheel and harmonic balancer professionally balanced, and more.

The engine also featured Kustom Headers, sourced from GM’s heavy-duty racing catalog, while the gearbox was a Muncie four-speed manual, with an M22 case, M20 wide gear ratios, and 3:70 axle ratio, for better street performance. The heavy diet, Richard implemented on the 1968 Corvette shaved significant weight and all of a sudden, the car sat too high. Richard fixed that by cutting two coils from each front spring and removing three leafs from the rear springs. He also installed Koni shock absorbers.

What struck me as an unexpected challenge, was that after losing 500 pounds, the owner then learned that he now needed to adapt the suspension, for it no longer was a heavy weight, and needed the right shocks for a lighter car. 

1 comment:

  1. Famous quote
    Who said Simplify and add lightness?
    Image result for add lightness
    Colin Chapman
    A great British racing engineer once said his philosophy toward race car design was “simplify, then add lightness”. That man was Colin Chapman, who founded Lotus and took the car company to great heights in the Formula One racing circuit.Nov 15, 2014

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