Hood vents for the engine
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Hood vents for the engine
I just got my EVO 8 and was thinking of putting a HKS RS kit. Since it's an open air filter that will suck hot air, will the hood vents help the HKS kit not to inhale hot air? If you think of it, hot air rises and escapes through the hood vents. What are your thoughts?
Originally posted by en1gma19
doesn't make much difference on turbo cars, the turbo would heat the air up after it's inhaled anyway. that's what the intercooler's for. don't worry about it
doesn't make much difference on turbo cars, the turbo would heat the air up after it's inhaled anyway. that's what the intercooler's for. don't worry about it
This is all basic physics, Thermodynamics breaks down to three laws.
1). You can't win.
2). You can't loose.
3). You can't break even.
What you want in any engine, Turbos included, is the greatest density of Air/Fuel you can get.
Density increases with pressure and with lower temperature. That is why you have a Turbo and an intercooler.
The amount of power you would loose with pre-heated air depends on how hot it is. I am guessing but 200-250 degrees would be a common under hood temp. So the compressed air leaving the turbo will be at least 100 deg higher than it would normally be. Heat is not lost, so you just keep adding it up.
The factory does things for a reason, you have to be careful when modifying and an open air filter could cost you power on a hot day.
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From: Turkey Town (Gobble-Gobble)
with a MAF meter it makes are huge different... drive ur car in 60 degree weather and in 110 degree weather then tell me theres no diference in performance... Density as stated before affects performance greatly... The whole goal for a turbo is to cram as much air as possible into the cylinder then combust it. Well dense air oviously contains more oxygen and can provide more oxygen to the combustion process then thin air can. Another reason why there is an intercooler after the turbo to try and condense that air back to something more efficent... If you had a MAP sensor it wouldn't make much difference... just that u might beable to sneek alittle cooler air into the intake becasue its less work for the intercooler...
i am not arguing the laws of physics. of course cold air is denser, that is why everyone saw increased boost when the weather got cold this past winter. what i am saying, is the difference between induction temperatures with an open air element intake and the stock, or even a cold air routed pipe, is trivial and nothing to worry about. The majority of people on these forums are running aftermarket intakes with no problems and are making gobs of horsepower. not something he should be concerned with. that's all
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Hot air does make a difference. You will never recover the density that you lost by taking in hot air. You will have less cooling of the charge through the intercooler due to the preheated air.
This is all basic physics, Thermodynamics breaks down to three laws.
1). You can't win.
2). You can't loose.
3). You can't break even.
What you want in any engine, Turbos included, is the greatest density of Air/Fuel you can get.
Density increases with pressure and with lower temperature. That is why you have a Turbo and an intercooler.
The amount of power you would loose with pre-heated air depends on how hot it is. I am guessing but 200-250 degrees would be a common under hood temp. So the compressed air leaving the turbo will be at least 100 deg higher than it would normally be. Heat is not lost, so you just keep adding it up.
The factory does things for a reason, you have to be careful when modifying and an open air filter could cost you power on a hot day.
This is all basic physics, Thermodynamics breaks down to three laws.
1). You can't win.
2). You can't loose.
3). You can't break even.
What you want in any engine, Turbos included, is the greatest density of Air/Fuel you can get.
Density increases with pressure and with lower temperature. That is why you have a Turbo and an intercooler.
The amount of power you would loose with pre-heated air depends on how hot it is. I am guessing but 200-250 degrees would be a common under hood temp. So the compressed air leaving the turbo will be at least 100 deg higher than it would normally be. Heat is not lost, so you just keep adding it up.
The factory does things for a reason, you have to be careful when modifying and an open air filter could cost you power on a hot day.
This is VERY true, but don't forget that there are these giagantic holes in the front of the car, they kinda let in a LOT of air, and if you look at the front of teh car and the hood vent, you can see that it is designed to suck in air down low and force it through the hood, this works amazing as a cooling factor and you do in fact get cool air while in transit, if you are really worried you can fabricate an air guide but the front of the car lets in so much air as it is.....