Building a custom cooling system means the filler neck has to go where the tank or radiator allows, not where a factory neck happens to sit. This weld-on billet neck accepts the smaller SAE Type B/43mm radiator caps and machines cleanly into an aluminum radiator, header tank or expansion tank, giving a heavy duty sealing surface in a spot you choose.

Moroso 63488 Billet Aluminum Radiator Filler Neck Features:

• Machined from 6061-T6 billet aluminum for a strong, corrosion resistant neck.
• Accepts small SAE Type B/43mm radiator caps.
• Weld-on design suits custom radiator, header tank and expansion tank fabrication.
• Includes a screw-in 1/8 in. NPT hose fitting for plumbing an overflow or recovery tank.
• Suited to racing and street performance cooling systems.
• Sold individually.