Hypercoils 6" OBD Coil-Over Spring - 2-1/2" I.D. - 550 lb. 36001BK make them the ultimate throttle

make them the ultimate throttle bodies for ease of installation and tuning

gasket seat * Deck thickness: 5/8"

Holley Nostalgia 2300 Carburetors

Threads are 7/16"-14 x 1

Coil Springs / Hardware / Spindles

Hypercoils 6" OBD Coil-Over Spring - 2-1/2" I.D. - 550 lb. 36001BK make them the ultimate throttleOptimum Body Diameter (OBD) Hypercoils feature a unique design concept that adjusts the body diameter of the spring relative to the end coils. The OBD design enables Hyperco to take full advantage of its ultra high tensile material by optimizing the applied stress through adjusting the spring's body diameter. HYPERCOILS because the most important race is the one you are in. Hyperco is a supplier of precision engineered, high performance suspension