Related Photo Galleries
Two of COMP Cams’ most popular SBF camshafts are PN 35-518-8 and PN 35-522-8. Both are Xtreme Energy grinds, the former measuring in at 224/232 degrees of duration at .050, and the latter with 232/240 degrees at .050. The wild card of the bunch was the 227/241-at-.050 Thumpr, which proved to be the best all-around performer in our 347. All three grinds idled well at 900 rpm, with the Thumpr providing a noticeably choppier disposition.