If you install a bigger camshaft on your vehicle and change the timing, you may benefit from an advance curve kit, as the mechanical advance for the distributor should be revised. If you change the compression ratio of the engine, you may also benefit from an HEI advance curve kit. The curve kit comes in handy if, because of a higher compression ratio, the engine is harder to start. The springs and weights in the kit are designed to advance the timing as the engine speed increases.
Things You'll Need
- Needle nose pliers
Remove the distributor cap, using the screwdriver to turn the locks. Remove the rotor. Remove the stock springs, "E" clips, weights and the center plate using your fingers, the screwdriver and the needle-nose pliers.
Pick a bushing set from the two sets that come in the kit. Pick the one that fits snugly on the weight pins. Press the bushings onto the weights, then install the assemblies into the distributor.
Reinstall the "E" clips. Pick the springs for the curve you want, based on the instructions with the kit . (The instructions contain graphics to help you decide which is correct for your application.) Install the springs in place of the old springs.
Reinstall the rotor and distributor cap. Remove the vacuum line from the distributor. Plug the line with a screw.
Set the idle at 750 rpm and the timing to the stock setting for your vehicle. You can find the stock setting in an auto repair manual. Reinstall the vacuum line. Adjust the idle so that the vehicle idles correctly in "Park" and "Drive."
Tips & Warnings
- Install the center plate as shown in the graphics that come with the kit, if the distributor turns clockwise. If the distributor turns counter clockwise, turn the center plate and the weights over.
- If you want to eliminate vacuum advance while accelerating, install Chevrolet P/N 1972511 (Vacuum Pot Assembly).
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