Only the front cam bearing is and needs to be grooved, and is the same size for the 215/300/340 and the sbb 350. So just order the 1 front grooved cam bearing and a 340 set, just don't use the front one in the set. The 340 cam bearings are progressively .030" smaller as they go in from the front of block, first one that is the same is 1.780" diameter then the next is minus .030" smaller @ 1.750" then the next is another .030" smaller and so on. When they revamped the sbb and went to a different intake and exhaust port layout they also made the cam bearings with the same 1.780" housing bores so the earlier cams won't work in a sbb 350. I hope this answers your question. GL Derek
