well, as we've seen, heat helps the vaporization of fuel, which if significant enough, CAN hurt VE due to expanding fuel vapor pushing air back into the plenum rather than sitting in the runner. it will also likely contain SOME unburned fuel.

a hotter mass also experiences less friction when it moves since it is less dense(so less molecules to scrub up against port walls and even other air molecules).

i haven't thought too much about it, but i think some of the OBD1 stuff does have a correction to the intake runner temp due to EGR being active. how complex GM's code engineers got here, i have no idea.



it would be interesting if the equivalent of the carbon cannister used for evaporative emissions could somehow be used in the exhaust to capture any unburned fuel and have it get sucked up through the EGR system. i'm not sure how much raw fuel could be collected though. i would think one would want to position a device immediately before the catalytic converter since the exhaust stream will be the coolest there(and most dense) before the cat uses the unburned fuel and does it's job as a catalyst.