I have some 305 Vortec truck heads # 12552520 and need to know what size the chambers are? They're off of a 97 truck. Mortec doesn't have much info about these heads. I need to know by Sunday evening, tonight preferrably. Thanks for any help.
I believe there 58cc`s, I`m not sure of the port size but it`s not as large as the L31 350 head, I don`t know of your use for these heads but it`s not recommended they be used on anything larger than a 305.
I have just installed these very heads on my 283 last week. They are 58 cc. Intake valve 1.84 and exhaust 1.74 I believe. Don't know about the runners though. They sound awesome on my little motor, I still have to retune the carb now as its running too lean now.