[Christ]

Daox -

I'm thinking that if you want to start with insulation, maybe the end tanks of the radiator and the hoses would be a good place to start. The hoses could be insulated with dead air by putting larger hoses over them and taping off the ends with heat-resistant tape.

Insulating your intake box and tubing might also help, marginally.

If you wanted to insulate the block itself, and don't mind replacing a couple gaskets, you'd have an easier time getting something in there if you removed the intake and exhaust manifolds. If you didn't want to replace the gaskets, you could still get some fiberglass or something in there to pack the block and wrap it all together with aluminum foil, if you wanted quick and dirty. The other approach would be to make an attempt at actually sealing the engine compartment, with a full belly pan, engine cover/blanket, etc.

You might not want the exhaust manifold in your engine sandwich, but then again, if you drive really conservatively, maybe it won't hurt?