Acceleration Factors?
 

Ok how do factors such as temperature, elevation, and humidity affect acceleration, and quarter mile time?

Re: Acceleration Factors?
 

I believe all those are inversly proportionate to acceleration..

Re: Acceleration Factors?
 

In english, higher temps, higher humidity and higher elevation will give you lower acceleration.

High barometric pressure, sea level at 40 degrees F would give you the best engine performance. But that cold would hamper tire performace so unless it was at the end of a warm day you would lose some power transfer to the ground to hard tires on cold pavement.

NA's are less suseptable to variances than an SRT because the SC compresses the air, amplifying the overall effect. Again cool dry, dense air matters as it increases the ratio of compression by amplification. The more dense the air, the more you can force into the cylinders. The heat of explosion is the same so more air is a bigger bang. Dryer air means a more complete explosion. Again bigger bang.
Sea level has more air per cubic foot that high altitude. Again, bigger bang.
Bigger bang, more HP and torque.

Hope that helps.


roadster with a stick

Re: Acceleration Factors?
 

Below sea level is a wee bit better, just make sure you cannot see any waves.:p
A little moisture is good, cars and bikes run better with a little moisture in the air. Water injection adds hp as well if I remember correctly.

Re: Acceleration Factors?
 

so, 2005crossfire6speed, wait till it rains in Death Valley during say winter when it's cool and I guess you'll get the best times.:confused:

Actually there is a huge difference between humid air and water injection. One makes the combustion chambers cool the other does not. Humid air does not cool the chamber. Humid air does not reduce pre-ignition knock. Humid air does not fire like water/meth. The moisture in humid air is already expanded (its vapor) unlike raw water, so the steam conversion is negligible. Then there is the matter of the compressor. On SC engines the water vapor doesn't like to compress and takes up room that could be usable O2. Humid air is bad. Period.

http://en.wikipedia.org/wiki/Water_injection_(engines)

I believe guys who actually go to the track will back this up. If not, I'll bow to their experience.

roadster with a stick

Re: Acceleration Factors?
 

You are correct, high humidity SUCKS! Makes your DA higher which SUCKS! I live race at 140' above sea level which DOSENT suck........:D

Re: Acceleration Factors?
 

My XF runs SOOO much better at lower altitudes.

Re: Acceleration Factors?
 

Actually,your post reminded me that, in my original post, I was not quite correct. NA's will suffer significantly at higher altitudes, say over 11,000 feet as they will not aspirate enough oxygen for good combustion. It was this phenomenon that led to the developement of the supercharger on aircraft engines.
https://kb.osu.edu/dspace/bitstream/...28_i02_013.pdf

franc

Re: Acceleration Factors?
 

Well if humidity is bad then im in trouble. im in mississippi and it is so humid here, i cant stand it. Dont know about elevation though

Re: Acceleration Factors?
 

In comparison to Colorado, Mississippi has no elevation. :p I don't think you will have to worry about elevation.

Re: Acceleration Factors?
 

Elevation will effect a NA motor 3% for every 1000ft. Elevation does not effect forced induction vehicles nearly as bad. have been told that a turbo engine is almost uneffected by elevation, something to do with the wastegate acounting for the loss of pressure and not opening until adequate pressure is obtained.