HELP ME 2 HELP YOU - please complete your Personal information: go to Menu>Profile>EditProfile>Personal>Signature> enter country code (UK,USA,etc.) your MEV, your donor's year and engine size (then click Save) This leads to faster trouble shooting!
First there's having enough air, often stock filters reduce the air intake with obvious results.
Then there's air temperature, the colder the air the better as cold air is more dense so has more oxygen in a given volume of air.
I have a book somewhere with figures showing performance gains from changing the air filter from stock, changing the air intake position and changing the air intake runner length.
“Life is not a journey to the grave with the intention of arriving safely in a pretty and well-preserved body. But rather, to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming .... WOW what a ride.”
TLDR; air at 50 degrees is ~10% less dense (and less bang) than at 22 degrees.
My old Puma's air intake (K&N cone filter, no airbox, no shielding but a much improved noise) used to get up to about 50 on a warm day sat in traffic. Thing is, when you start moving, it cools down to atmospheric temperature within seconds. If you're in traffic, it's very unlikely you need Wide Open Throttle and to release all the horsies.
So those cool-air feeds people buy, ah, I dunno if they're worth the £200+ people pay for them. As an aside, anyone want the one that came with my Focus donor? :-)