How does outside air temp affect HP?

[m3f_Fishey]

Was wondering how much it affected the HP on a N/A car...

[m3f_PurpleM3Pursuit]

on all cars.. the cooler the air.. the more hp.. the hotter.. the less hp.. but don't forget.. there is also traction involved.. and im sure there can be a significant difference.. depends on the temp swing

[m3f_M3AN_5f4dc0ba80]

Originally posted by Fishey

Was wondering how much it affected the HP on a N/A car...



Nowhere near as much as a FI car but you know this.



I've seen variances of up to 8% on a NA car whereas for my FI cars it's been up to 25% (massive!). Even turning off the intercooler water sprayer on my Evo made about 5% - 10% difference, I was astonished.



It's all about density and you're not going to ever get much more than 1 bar into a NA car at sea level.

[m3f_astan100_7ef66fbe89]

I remember reading an article in one of the magazines about a test in Death Valley with a lot of different trucks.



They said the ones that seemed least affected were the FI ones...Nissan something?



I thought that was interesting.

[m3f_mgraney_5eb4461672]

I read somewhere that every 11 degrees Farenheit equals a 1% HP difference.

[m3f_CarQz17_da02e24fb5]

i heard of a guy running a WRX at a drag strip that put a bag of ice in front of his intake and intercooler, and he ran a hell of alot faster..

[m3f_PurpleM3Pursuit]

5.0's do it all the time.. my buddy put a bag of ice on is FMI.. works well.. but it makes sense..