Breaker weight spring set. Extreme duty - 70-99 B.T.(excl. TC); 71-03 XL (NU). With mechanical advanced ignition 942324 break & rivet most 520

break & rivet most 520

wrenching or storage

these are not identical

SHINKO SUPER CLASSIC TIRE 270 4

Fits double springs with damper

Breaker weight spring set. Extreme duty - 70-99 B.T.(excl. TC); 71-03 XL (NU). With mechanical advanced ignition 942324 break & rivet most 520Stronger than stock. For a slower advance curve, used to help solve detonation issues. Less breaker weight rattle during idling and improves idling stability. Note that stronger springs may require carburetor adjustment (richer). Note: 516300 is standard replacement, 516301 is heavy duty, 516598 is extreme duty. Mixing different spring strengths will give additional fine tuning options.