170 vs. 225

The few things I have learned in the last few years (that I can remember) is .............. The slant six head was designed for the 170/6, and was never changed for the longer stroke bigger bore 198/ and 225/, I agree with Bills finding that C.I. is a plus for getting more power easier then it is by trying to get bigger numbers with a 170/6 (low deck) block.. all of the 170/ engines have a steal crank and larger rod and crank bearings, witch will handle more boost or Nos, the early 225 engines also have steel cranks and big rod and crank bearings till 197?, but at one time (not sure) they went to a cast-iron crank and smaller bearing size..( I could be wrong on this bearing/gernal size) So if and when I go 225/6 the head work is going to be a must do for the bigger bore and longer stroke and it will net more H.P.
H.P.
170 1967-1969 8.5 to 1 115 @ 4400 155 @ 2400
225 1964-1971 8.4 to 1 145 @ 4000 215 @ 2400 note,this big hp, compared to the rest of the 225/6 engines
225 1972 8.4 to 1 110 @ 4000 185 @ 2000
225 1973 8.4 to 1 105 @ 4000 185 @ 1600
225 1974 8.4 to 1 105 @ 3600 180 @ 1600
225 1975 8.4 to 1 95 @ 3600 170 @ 1600
225 1976-78 8.4 to 1 100 @ 3600 170 @ 1600
225-2V 1977-78 8.4 to 1 110 180

This info was found here http://www.allpar.com/slant6.html