Here area couple of pictures of a set of Brodix 18 degree SBC CNC cylinder heads a customer brought me. the engine would rev to 6300 rpm and then the HP would flat line. these are the heads that Brodix sells that you can run standard valve train on. One of the problems is the 2 nd choke point is to small and there is not enough cross sectional area at the apex of the short turn. I raised the port top and bottom and added a generous radius. This put me in the 2.640 CSA. Since there was minimal room to grind i added some area to the short turn area and epoxied a reverse fin in the back of the bowl to help stabilize the air. Heads ended up flowing 310 cfm @.500 lift and about 380 cfm @ .700 lift.
Engine originally made 680 HP @ 6300 and then flatlined. I dynoed the engine with no other changes besides the heads and intake match. Now the engine makes 748 Hp @ 7500 RPM's. In the customers dragster it picked up 1 1/2 tegnths and 4 MPH. (7.60 ET @ 184 MPH...not bad for a 406CI. SBC. |