slant six MPG build e 85

ok so here is the deal i just finished getting my 225 rebuilt so its going to be a driver again so i want to build a extra motor and balance power with economy
so this is what im thinking

170ci
10.5 to 1 cr
big valves (1.75 and 1.5)
hei style ign control
mpfi (mega squirt I)
intercooled turbo (6 psi for street 15 for track)
E85 with meth injection
balanced to 8k
and a a833 od if i can find one or a T5

goals are 35mpg freeway and 25 city with ~400hp

any ideas or sugestions and why (kinda a open forum thing just getting more ideas)