You need more experience and less theoretical BS and marketing. There was a 170 cu in limit and I was talking about historical fact, the other manufacturers were not even close. All /6 use the same bore, only the rods and cranks change until the smog era. A 170 has the shortest stroke and a shorter deck, and will rev the best of the /6's. Also being the smallest cu in using the same head will naturally rev higher. The 170 I put together would easily beat a Chevy 235 straight six in anything an engine does for next to no money.
