They feature the popular Holley HP Series race-ready mainbody, but are calibrated for street/strip duty. The base plate has several vacuum ports to cover PCV, power brakes etc. Other features include mechanical secondaries for optimum tire-turning performance, power valve blow out protection, non-stick gaskets, adjustable air bleeds, four corner idle system, Ford kick-down and down leg boosters. Their larger CFMs make them perfect for hot small blocks as well as big blocks. Street HPs have been available for sometime in 650 and 750 CFM. For more information contact Holley Tech Service, 1801 Russellville Road, Bowling Green, KY 42101. Telephone 270-781-9741 (now available on Saturdays). For nearest dealer: 1-800-HOLLEY-1. Or visit us on the web at www.holley.com