That's amazing how much better the 170 does on the highway. Your experience with the 225 mirrors mine; I get around 18 or so on the highway, but my car originally had a worn out 170. I guess the little bit of extra power is a fair enough tradeoff.
170's are the greatest little motors for a driver.With a 4 speed behind it (not an overdrive one) they are lots of fun to drive. That little short stroke motor is very responsive when you set it up with the right trans and rear.
