Incorrect on both points [well kinda on the 2nd].
The hotter your engine runs the more efficiant it is and the more power it will make. The problem is when the engine runs hotter the intake air temps get higher which reduces the intake charge. If you could run the engine really hot and keep the intaked air really cold you'd make the most power possable.
As for engine ice or water wetter, it will only help if your cooling system already can't cope with the heat produced, otherwise the thermostat is only going to let the temps get down so far before it closes off coolant flow to keep the temp up.

 

I can't stand that b*tch.

 

It is actually running a little rich so when hot it doesnt atomize the fuel aswell as when its cool. If it gets too cool it will need even more fuel so it will go lean. If you were to lean it out a little more when hot weather using a pc3 or such you would have the same crisp response.

 

great posts guys learning alot....thx

 

Wow there are a lot of conflicting views on this. Just want to clear a few things up.

If your engine temp is too cold(coolant temp) then the ECU will not be at the highest performing timing table and will not allow as much timing advance and therefore will reduce power.

The colder the air the more dense so there is going to be more power as your will run a tad bit leaner but the ECU should correct for this as it should be measuring the air intake temp and be compensating for the fuel that it needs. So you will be making more power and lessen the chance of knock.

But on the other side the hotter the air is higher the velocity and your engine will be moving it in and out faster and with less effort.

Also the comment on the hotter the air the worse the fuel atomization is completely backwards. Think of heating up water the more heat the more steam to a boiling point.

Basically in the end cooler intake temp equals more fuel being able to be added to keep the AFR stoich which means more power.

 

I don't think people have a clue what cold air does. Think what is nitrous oxide? If you can figure out what that does then bam a lot of stuff will make sense with cold air.

 

And what did my reply (the first one) say?