The 307 had teething problems when GM first used them, mainly head and camshaft issues. The same people that love a stroked 350 (ex.383) hate a stroked 283 (307). We ran a circle track car that was in a class with a 312ci limit so others gathered up the much harder to find 302 which was legal with a 0.060 overbore. We used a homemade 307 with a 4 bolt splayed main caps 0.030 283 block and the 327 steel crank. With good heads and good internals including roller cam and rev kit both the 302 and 307 could turn in the 7800-8100 rpm range and live. Only thing is the longer stroke 307 just killed the 302's off the corner and won the season championship. With that said, a factory 307 is perfect for you to practice your mechanicing on since it will weigh the same as scrap assembled or disassembled.
