February '20

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30 THE SHOP FEBRUARY 2020 a suburb just south of Chicago. Dyno-tuning was all the rage in the 1960s, because it maximized performance based on precision rather than seat-of-the- pants tuning. If you lived on the South Side, Willy's was the place to go. It had two concrete block dyno cells, each equipped with a Clayton Chassis Dynamometer and an impressive bank of Sun and Clayton instruments mounted on the wall. Willy's was known for having talented techs running the dynos and setting up the cars. Nearly everyone in the area who was serious about performance went there. Since Willy's worked on a first-come, first-served basis, on a typical Saturday morning, by 6 a.m. muscle cars and hot rods of all kinds would be waiting in a line that stretched around the block. For this segment, we installed the parts, recurved the distributor and dyno-tuned the Day 2 Camaro at VanGordon Racing in Upland, California. Jim VanGordon applied his years of experience as a well- known classic muscle car tuner, spec race series engine builder and professional drag racer to extract additional horsepower from the original numbers-matching Chevrolet L48 350. We ran the Day 2 Camaro on the Van- Gordon and Whitfield Dynojet Dyna- mometer before and after the performance upgrades to see just how much horsepower was gained using tried-and-true vintage performance parts and tuning techniques. One thing to remember when it comes to turning up the wick on a vintage muscle today—unlike 1969, when my original Camaro enjoyed a steady diet of 102- octane leaded Sunoco 260 gasoline—the highest octane in California is a paltry 91-octane unleaded. And it's a highly oxygenated formulation that is cut with at least 10% or more ethanol, making it a far cry from the pure 102 we ran back in the sixties. This means we need to be a little more conservative when it comes to ignition timing and overall setup to minimize the risk of detonation. MORE POWER TO YOU The first order of business was to establish a baseline with the Camaro in stock form. While the 350 ran smoothly through the gears on the dyno, it was obvious that by 4,600 rpm it was done and the horsepower curve had peaked. This was very close to the original GM spec, which called for 295 gross horsepower at 4,800 rpm. After a solid week of hard work, all of the parts were installed. The next step was to fire up the engine, set the timing, adjust the carb and break in the new cam. Then it was time to strap the Camaro back onto the dyno and find out if the vintage speed parts and good old-fashioned tuning tricks had produced the results we were striving to achieve. VanGordon had set the engine up with a base tune and made the first run on the dyno an easy one. The Dynojet instru- mentation showed that the fuel curve was right on the money and the engine sounded much more potent than when it was stock. He rechecked the timing, set the distrib- utor for 36 degrees total advance, and then made two full-throttle runs through all four gears in quick succession. Before we started the build, VanGordon predicted an increase of 35 to 50 gross horsepower based on the parts I had The Way We Were Doug's Headers Virtues: Doug's four-tube headers (1-3/4-inch tubes with 3-inch collectors) flow significantly better than the stock cast iron exhaust manifolds. They increase horsepower and no mods were required for installation. Refurbish & Recurve Origi- nal Delco Remy Distributor Virtues: Set up to run up to 7,000 rpm while achiev- ing full advance at 1,800 rpm for enhanced engine performance. Jim VanGor- don changed the bump bushing under the weights to limit the amount of cen- trifugal advance and used softer springs for less ten- sion on the counterweights to enable the distributor to achieve maximum advance sooner. He chose Stan- dard Motor Products Blue Streak Heavy Duty points, condenser and rotor. Classic Industries Heavy Duty Motor Mounts Virtues: The new Classic Industries heavy-duty motor mounts are significantly larger than stock and incorporate a torque restraint that prevents the mount from splitting in half like the originals.

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