PRICING IS FOR A SINGLE TRUMPET--PURCHASE TWO IF YOUR CAR HAS TWO BOV's.

The ability to change the sound of a blow-off valve is increasingly becoming an important issue with buyers, who want to sound different from everyone else. The GFB Whistling Trumpet can be used in place of the standard trumpet on all GFB valves, and will make the whistling sound more and at a slightly higher pitch than the stock trumpet. It is necessary to run the valve so that all (or most) of the air vents through the trumpet – Respons valves will typically not generate the velocity required to whistle when set to 50/50 venting. This part is recommended for Respons and Hybrid II valves.