289 C5AE-B's
 

I know they have a 54cc chamber. I currently have a 67 mustang coupe with a 67 289 with: late 70's 302 heads, edel performer intake, 600 edel carb, hooker comp headers, XE 268 cam, MSD electronic ignition. What size of valve should i bump themup to or should i let them be... They seem to be very clean, but my buddy is going to check them out to see...

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