[dremd]

Few thoughts

1) Don't over cool your oil ( I think 160F is about as low as you want to go) May still be very feasible.
I THINK the 1zz has an oil 2 water heat exchanger, I can't remember, I'll look tonight. In which case the water would hold the Oil temp up near 200. But then why not just use water?
2) If you have ever tried to heat a 1966 VW bus you know that it is incredibly difficult to get very much heat out of the exhaust manifold, there is a very high temperature, but it cools incredibly easy. Not sure how much energy is required here . . . . .
Check out a heat exchanger from an Air cooled VW for ideas. . . . .

How hot do you want the intake air?