Just curious as to what the difference between the air intakes that sit right up in the engine bay and require a heat shield vs. the ones that run out and down into the bumper? only thing i hear is "water might get in it" other that that does one give more airflow or better air flow? Thanks.
Air intake question
03mk4wolf
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lets just go with that because its getting a little out of hand:laugh::laugh:
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~$150 for bent pipe and a cone filter and some couplings? No thank you for me
be careful with those Ricer logics... cheap solutions are not the best
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you're right, the stock airbox works perfect.
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Feed a hose from outside the engine bay into the stock airbox.
Best, safest, cheapest way to upgrade your air intake.
Lets use your login in other instances![Image]()
Exhaust: $500 for a complete 3" Exhaust? No, the stock pipes work perfect
Chipping: $600 for an APR Chip? No, the stock ECU is perfect
No just no :facepalm:
The problem is not the cold air, the problem is the restrictive stock air filter
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K&N Drop in filter would take care of that issue right quick!
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lol yur dum
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stand up next time, you might catch that joke.
lmao i don't think you understand how thermodynamics work.
anyway in for these so called proven dyno results.
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Maybe not, but I don't know if you do cause you haven't argued anything!
Don't attack me, make an argument.
As the intake air temperature increases, the compressor has to work harder to achieve a given compressor pressure ratio at the compressor outlet and this means the turbine has to work harder to power the compressor and since the turbine is powered by the heat energy in the exhaust flow this means the exhaust gas temperature must increase. Since the intercooler is downstream from the compressor it can't possibly compensate for this "increase in required EGT penalty" due to the increased workload on the compressor in maintaining a given CPR for higher AIT!
That is my understanding. Heat is the energy the turbo needs to work, but too much heat will cause an engine knock. Is there a happy medium?
cold air is cold air in a sense but you won't notice a power difference because of slightly colder air entering the turbo, however it might help with heat soak and prolong the life of your turbo, slightly.
all in all, its really not worth the extra money/risk. most people on here have lowered cars and don't even run fender liners. having a filter 3 inches from your tire isn't exactly a great idea.
all in all, its really not worth the extra money/risk. most people on here have lowered cars and don't even run fender liners. having a filter 3 inches from your tire isn't exactly a great idea.
I just happened to come across this while I was working on Thermal Systems homework, so I thought I would incorporate it. Here is a quick graph I worked up of compressor inlet temperatures vs delta T (heat added to air) for three given inlet temperatures (50, 75, and 120 degrees F; 50 and 75 would likely be CAI depending on climate, and 120 is a likely under hood temp also depending on climate) and two different pressure ratios (2.36 and 1.82; 20 and 12 psi boost respectively, at sea level)
BTW: This is my first post here, and first post in general for a long while, sorry if image gets screwed up.
![Image]()
As you can see, the energy (heat) that gets added to the air is not linearly but exponentially proportional to the compressor inlet temperature. This difference becomes more drastic as boost pressure is increased and/or compressor efficiency is decreased (these assume 70% efficiency which is being generous). Now, the effect on power I'm not sure of, I know I've done the calculations before and it was at least somewhat significant, if I have time, I'll try to do those as well. This also does not include effects of intercooling, but if I remember correctly, the temperature drop through the intercooler is linearly proportional to the intercooler inlet temp, meaning it will not make up for additional delta T. But don't quote me on that one just yet.
Long story short, hot air intake (mounted in engine bay) bad, cold air intake (as in cold air being induced not necessarily a "CAI") good.
Oh, and to help explain what I think Konkordmusk was trying to say: Hotter air is less dense, therefore the compressor wheel must do more work on the air to compress it to the desired pressure (somewhat proportional to density). The more work the compressor must do, the more heat it will impart on the working fluid due to no process being 100% efficient.
Thanks for your time, I'm gonna go get some more coke so I can finish all this damn homework/projects now.
Edit: Y axis should say (T out - T in)
BTW: This is my first post here, and first post in general for a long while, sorry if image gets screwed up.
As you can see, the energy (heat) that gets added to the air is not linearly but exponentially proportional to the compressor inlet temperature. This difference becomes more drastic as boost pressure is increased and/or compressor efficiency is decreased (these assume 70% efficiency which is being generous). Now, the effect on power I'm not sure of, I know I've done the calculations before and it was at least somewhat significant, if I have time, I'll try to do those as well. This also does not include effects of intercooling, but if I remember correctly, the temperature drop through the intercooler is linearly proportional to the intercooler inlet temp, meaning it will not make up for additional delta T. But don't quote me on that one just yet.
Long story short, hot air intake (mounted in engine bay) bad, cold air intake (as in cold air being induced not necessarily a "CAI") good.
Oh, and to help explain what I think Konkordmusk was trying to say: Hotter air is less dense, therefore the compressor wheel must do more work on the air to compress it to the desired pressure (somewhat proportional to density). The more work the compressor must do, the more heat it will impart on the working fluid due to no process being 100% efficient.
Thanks for your time, I'm gonna go get some more coke so I can finish all this damn homework/projects now.
Edit: Y axis should say (T out - T in)
Sorry, but they didn't really disprove anything except that a couple guys with hand tools can't out smart millions of dollars of R&D. First, I'm not advocating cold air intakes, most the ones on the market are absolute crap. But lets be honest, the RB26 engine is a very well designed engine and a simple air intake isn't likely to make much of a difference at all. However, if you're talking about a mass produced econo/sport box, although the engineers are much smarter than most of us, the bean counters are going to micromanage a few decisions. The bottom line is, the colder the air the better, period; but unless your intake is super restrictive or sucking the air off the header, you won't see a huge difference by the time it makes it to the wheels. And the temperature ranges they tested were not realistic, what about after you've been driving a while and everything under the hood is heat soaked.
Definitely not saying everyone needs to go out and buy a cold air intake and they'll be blowing doors off Ferrari's (at least not until I complete my intake design, lol), but don't say it's worthless. However, it is absolutely worthless to buy a metal cold air intake. What's the point of sucking in outside "cold" air to send it through a conductor that's going to heat it up to engine bay temps.
Crap, I need to sleep!!:banghead:
Definitely not saying everyone needs to go out and buy a cold air intake and they'll be blowing doors off Ferrari's (at least not until I complete my intake design, lol), but don't say it's worthless. However, it is absolutely worthless to buy a metal cold air intake. What's the point of sucking in outside "cold" air to send it through a conductor that's going to heat it up to engine bay temps.
Crap, I need to sleep!!:banghead:
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