What is Head-Quarters USA?

Head-Quarters began in 1969 with Doug Coffey and a vision. Since then, the demand for Doug's special blend of high performance and dependibility has been overwhelming. Head-Quarters USA was established in order to better serve the needs of retail customers in the US. Nothing else has changed...same great products by the same great company. Welcome to Head-Quarters USA.

Flow Charts

ALL OUR TESTS ARE PERFORMED ON A FLOW BENCH AT 10lbs TEST PRESSURE


INTAKE FLOW

Head

Valve

.100

.200

.300

.400

.500

.600

Total

Stock

1.84 HD

36

76

108

122

126

127

595 cfm

HQPorted

1.90 HQ

37

79

115

137

137

142

647 cfm

Stock SE

1.90 HD

33

67

96

119

136

146

597 cfm

Ported SE

1.90 HQ

36

72

100

122

139

150

610 cfm