Cool Air = Faster than normal Car
It is cold in Vancouver today.
- 1 degree Celsius ... 30 degrees F. Just below freezing. On the way home after a long day of work, on a deserted country road - i decided to do a standing start on dry pavement. I must have mashed the accelerator just right - because the V-8, E550 took off like a real beast. The jolt of power really brought a smile to my face. I know NA engines like cool air - like an inter-cooler gets more HP / Torque. I must have been well on the way to a well below sub 5 second 0-60 run. Took my foot off the gas because my stomach felt like the start of Rocking Roller Coaster at Disney. It was awesome ... the ESP light flickering in the darkness as the car was barely holding traction. Very cool experience ... got close to home and realized I was in Eco mode ... Usually I switch to Sport as soon as Istart the car. |
It’s the fastest sedan I have ever owned including the early 4 door C32 AMG. Yes, it loves cold air. |
Originally Posted by ChrisB
(Post 7675964)
It is cold in Vancouver today.
- 1 degree Celsius ... 30 degrees F. Just below freezing. On the way home after a long day of work, on a deserted country road - i decided to do a standing start on dry pavement. I must have mashed the accelerator just right - because the V-8, E550 took off like a real beast. The jolt of power really brought a smile to my face. I know NA engines like cool air - like an inter-cooler gets more HP / Torque. I must have been well on the way to a well below sub 5 second 0-60 run. Took my foot off the gas because my stomach felt like the start of Rocking Roller Coaster at Disney. It was awesome ... the ESP light flickering in the darkness as the car was barely holding traction. Very cool experience ... got close to home and realized I was in Eco mode ... Usually I switch to Sport as soon as Istart the car. Another thing that that makes it stronger is to turn the A/C off. The compressor can be running even during cold winter climate for de-frosting. It takes aboit 10% of the fuel mileage so it is quite big power consumer. |
Cold air is great for engines :) Simple as that. Imagine if you had the Bi turbocharged E550 :) With AWD. Sport Mode on. No A/C on too helps
|
Originally Posted by C280 Sport
(Post 7676165)
Cold air is great for engines :) Simple as that. Imagine if you had the Bi turbocharged E550 :) With AWD. Sport Mode on. No A/C on too helps
|
Originally Posted by KEY08
(Post 7676341)
yes, my exact current 550. I also had a 2010 N/A 550 4M. Both wicked fast and still prefer the sound of the N/A over the TT. |
Cool air has more oxygen in it than hot air. So if you run a fixed air/fuel mixture, you get more power with cool air than hot air.
|
Originally Posted by C280 Sport
(Post 7676366)
Really? Most people say otherwise. Interesting! Why so? Sound? Feel of it?
|
Very cool. Too bad I live in Florida. On the plus side, it was 80 and gorgeous today.
|
Originally Posted by thefisch
(Post 7676540)
Very cool. Too bad I live in Florida. On the plus side, it was 80 and gorgeous today.
|
Even if the car is 0.1 second faster, even with stop watch it is not measurable.
So we are talking 99% placebo effect here? Than remember that dense air make bigger air drag. |
Originally Posted by kajtek1
(Post 7676679)
Even if the car is 0.1 second faster, even with stop watch it is not measurable.
So we are talking 99% placebo effect here? Than remember that dense air make bigger air drag. When I worked at a gas power plant, it was evident in the power output, hot summer days the plant struggled to do 270 megawatts, normally it was around 300, in the winter it could go as high as 340. |
Originally Posted by thefisch
(Post 7676540)
Very cool. Too bad I live in Florida. On the plus side, it was 80 and gorgeous today.
|
Originally Posted by kajtek1
(Post 7676679)
Even if the car is 0.1 second faster, even with stop watch it is not measurable.
So we are talking 99% placebo effect here? Than remember that dense air make bigger air drag. Assuming the volume and pressure stay constant, like is the case with N/A engine we can write the equitation as n = (1/T) x (PV/R). In this formula (PV/R) stays constant as assumed above. Now the temperature T is the absolute temperature and for 90 F it is 305.4 K and 40 F is 277.6 K So the amount of air moles (n) at 90 F is n = (1/305.4) x (PV/R) and at 40F n = (1/277.6) x (PV/R) The ratio of the amount of air moles is then 305.4/277.6 = 1.10, i.e. 40F air has 10% more material than 90F air in the same volume. This means 40F air has 10% more oxygen than 90F air meaning the engine control system can spray 10% more fuel to burn the oxygen. This should result in 10% more power with the same throttle opening. With an engine with almost 400 hp it is roughly 40 hp increase in power and this should indeed be noticeable. In my car is certainly is. And some tunes advertise only about this magnitude power increase so if those are noticeable so should the effect of the lower air temperature also be. Turbo engines are probably different and I don't know how the air temperature after turbo chargers is controlled but the max pressure is controlled with the waste gates and volume entering the engine should stay pretty much the same so if the air temperature drops the above calculation should somewhat apply to turbo charged engines too. |
As the the thermodynamic equation predicts - if in actuality there is a 10% increase in power (considering 90 F air vs 40 F air) ... does that relate directly to 0 to 60 acceleration?
If 5 second run (that may be a common feeling for an E 550 driver - which is impressive enough) turns into a 4.5 second run ... that would probably produce noticeable physical sensations in the body. I believe that is what put the smile on my face. More than a pure placebo effect. Although that was in play as well. |
Originally Posted by ChrisB
(Post 7677273)
As the the thermodynamic equation predicts - if in actuality there is a 10% increase in power (considering 90 F air vs 40 F air) ... does that relate directly to 0 to 60 acceleration?
If 5 second run (that may be a common feeling for an E 550 driver - which is impressive enough) turns into a 4.5 second run ... that would probably produce noticeable physical sensations in the body. I believe that is what put the smile on my face. More than a pure placebo effect. Although that was in play as well. |
Originally Posted by ChrisB
(Post 7677273)
More than a pure placebo effect. Although that was in play as well.
http://kalecoauto.com/index.php?main...&products_id=8 |
Originally Posted by Arrie
(Post 7677101)
Using the ideal gas law PV = nRT you can easily look into this.
Assuming the volume and pressure stay constant, like is the case with N/A engine we can write the equitation as n = (1/T) x (PV/R). In this formula (PV/R) stays constant as assumed above. Now the temperature T is the absolute temperature and for 90 F it is 305.4 K and 40 F is 277.6 K So the amount of air moles (n) at 90 F is n = (1/305.4) x (PV/R) and at 40F n = (1/277.6) x (PV/R) The ratio of the amount of air moles is then 305.4/277.6 = 1.10, i.e. 40F air has 10% more material than 90F air in the same volume. This means 40F air has 10% more oxygen than 90F air meaning the engine control system can spray 10% more fuel to burn the oxygen. This should result in 10% more power with the same throttle opening. I’m going to try my best to remember this little factoid so I can sound smart one day down the road. |
Things you can learn on the net :)
|
After 45 minutes of driving.. at a traffic stop in Houston, TX
https://cimg5.ibsrv.net/gimg/www.mbw...2c96870ca6.jpg |
You have 76F at 8 AM in Houston?
How did you get the oil temp display? |
Originally Posted by kajtek1
(Post 7677943)
You have 76F at 8 AM in Houston?
How did you get the oil temp display? You can get the coolant temp + engine temp + current gear display + lap timer etc by activating the AMG Menu on the instrument cluster (even Non-AMG vehicles). Of course you will need MB SDConnect + Vediamo + some expertise. |
Last year I tried to show my ditz neighbor why his cheap aftermarket "cold air intake" caused his car to perform worse not better.
It was just sucking in underhood air, and the aluminum tube acted like a big heat sink. I hooked up my scanner to show real time data. This was in Texas late summer. Stock airbox and inlet IAT temp 96d F Aftermarket air intake IAT temp 134d F MAF sensor gm/sec reading increased with cooler air inlet temps, I figured due to denser air. Short term fuel trim range also increased with the after market intake, I took it to be due to a leaner condition. I doubted the cone filter flowed any better than a good quality stock paper filter. It was actually a hot air intake that made more noise. I think cooler denser air is a good thing especially when its free as in outdoor temperature drop. The nice thing is that with computer controls the vehicle can take advantage of it! |
Another near freezing night and a good acceleration run on the way home. Has anyone ever noticed how the car reacts differently when the gas pedal is stabbed very quickly? Toe pushed up into the footwell. i don’t think it is my imagination. Gas pedal monitored for maxacceleration under under certain movements of the pedal? |
Originally Posted by ChrisB
(Post 7688004)
Has anyone ever noticed how the car reacts differently when the gas pedal is stabbed very quickly? Toe pushed up into the footwell.
|
All times are GMT -4. The time now is 05:26 AM. |
© 2024 MH Sub I, LLC dba Internet Brands