318 rebuild/upgrade

I'm prety sure the std Performer "318/360" hase the smaller port window that the 318/273 share. I'm also pretty sure they didnt list the 273 application because the earlier 273s had a different angle for the last two bolts on each end. Think that ended in '66, but I'm not certain. The Edelbrock tends to be a high torque/great low speed intake, and the LD4B is more like a factory 340 style, just in aluminum.

Pyro, If your car has the original 318 (meaning '68?) 318, you already have smaller chambers than the 589s have. By a bit. '68-71ish 318s had smaller open chambers. I like to use them when I needs more squeeze on a newer LA...If you're looking for power, I would either use your exisitng heads, fit them with 1.88/1.609 valves, good valve job, springs, trim the guides, etc. and run them; or get a set of Magnum heads, have them done up, and run them. That would require a little more work, and parts, but I think they would be your best bet.