QA1 High Travel Coil-Over Spring - 2-1/2" I.D. x 10" Tall - 500 lb. RU003003XL please use the Manifold Reference

please use the Manifold Reference Dimensions guide

Straight stemmed XH-424 stainless exhaust valves and NK-841 stainless intake valves have chrome stems

9 wideband to relay AFR information to the ECU for accurate reading and precise tuning control

Rugged design with two types of clamps guarantees a secure fit

load capacity and durability

QA1 High Travel Coil-Over Spring - 2-1/2" I.D. x 10" Tall - 500 lb. RU003003XL please use the Manifold ReferencePowder Coated, Chrome Appearing Silicon Manganese SteelAll QA1 springs are manufactured using the highest quality chrome silicone. This material offers high strength, consistency and longer life. Cold Wound Heat Treated Shot PeenedAll QA1 springs go through intensive manufacturing processes to ensure consistency, accuracy and durability. Squared EndsAll QA1 springs are ground at both ends to ensure straight, consistent and accurate operation.