New Chevrolet BB RS-X Spread port cyl. heads
Moderator: Team
New Chevrolet BB RS-X Spread port cyl. heads
FYI The new heads have 3 part numbers.#19432393 is an unported bare casting. Valves and guides included but not installed. As cast ports and chambers with an unmachined deck. #19419908 is fully machined, but without valves or valve springs. Seats and guides are installed. 449cc Intake port 161 cc exhaust ports and 70cc Chambers. #19431810 is fully machined and assembled with titanium valves 2.45 1.80 w 5/16 stems. Springs are ovate beehive 1.589 OD 10 degree retainers with a 1.115 OD. Flow for those who care is 481 Intake, 347 exhaust. Deck is .750 thick. Cheers everyone