These are the ultimate in water cooled Hemi cylinder head technology. By reducing the angle of the exhaust valve from 23 to 21.5 degrees, we are able to fill these heads with monstrous 2.42 intake and 2.00 exhaust valves while retaining the stock rocker geometry. The larger valves enhance the already excellent flow characteristics of the Stage V Hemi head to the point where there is literally no automotive head in existence capable of coming close. An such as when engine displacement approaches the 600 cubic inch mark.

If you are building a Hemi for Bonneville, blown fuel boat drag racing, Pro Mod or virtually any application where solid billet heads are not legal or water cooling is required, the Stage V Big Valve aluminum head is for you. Works best on bore sizes of 4.50 or larger to eliminate shrouding and prevent valve-to-bore contact. A competition port and polish procedure is strongly advised. As with our other Hemi heads, we can machine the Big Valve head to accept dual spark plugs.