OFFICIAL 2009 - 2011 SPECIFICATIONS FOR NASCAR SUPER …

(ii) Ford Cleveland 2.055 - 1.656 (iii) Ford Windsor 2.055 - 1.625 (E) Cylinder head may be port matched a maximum of one-half inch (1/2 inch) into the intake port. Exhaust ports may not be altered. (F) Cylinder head valve angle must remain within one (1) degree of OEM standard production head. ................
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