Product DescriptionGM Chevy V8 HEI Distributor Mechanical Advance Re-Curve Spring Kit
This H.E.I. Advance Curve Kit is designed to fit all GM & Chevrolet H.E.I. distributors. This kit comes with 3 sets of advance springs to allow you to adjust the rate of spark advance from quick (Brown), to super-quick (Silver), to ultra-quick (copper).