Sacrilicious
boom boom!
- :
- Cosmic Blue MS3 of hawtness!
you mean fan moving air into the engine bay like a moving car at 30mph would?
SRI vs CAI on the DYNO!
- Thread starter driver311
- Start date
Sacrilicious
boom boom!
- :
- Cosmic Blue MS3 of hawtness!
here's the bottom line: this thread is about the best-backed argument EITHER WAY for this "fight". the best the CAI people can come back with is that the SRI is sucking up "hot engine bay air"...yes, this matters when you're sitting at a light, but once you get moving again, the engine bay is getting all sorts of cold air from the outside.
...and then there's the matter of the intercooler. ya, you have hotter air going into the turbo, but that air gets compressed to 15psi and heated up to 200F+...then it gets cooled down by the intercooler using ambient air, leaving the differences not NEARLY as noticeable. there's a reason why people who have gone to the cobb SRI from the MS CAI say they don't notice a bit of difference...
remember: we're driving a turbocharged car...not a NA one.
...and then there's the matter of the intercooler. ya, you have hotter air going into the turbo, but that air gets compressed to 15psi and heated up to 200F+...then it gets cooled down by the intercooler using ambient air, leaving the differences not NEARLY as noticeable. there's a reason why people who have gone to the cobb SRI from the MS CAI say they don't notice a bit of difference...
remember: we're driving a turbocharged car...not a NA one.
Ghost Rider
Banned
Yet some folks refuse to comprehend this..(screwy)
happy and angry
Member
It won't be taking hot engine bay air when moving. Oy.
Ghost Rider
Banned
H & A, this guy is a known troll, he/ she just goes around planting seeds of hate and discontent towards any ones views and or ideas that suggest that the Cobb SRI is in anyway better / equal to a CAI.
whitey4311
Member
- :
- MS3 GT Black Mica w/nav
Funny I have not been banned x4 under different names like you Ms3077, hard2kill, ghost rider, usmc98, and 1 more that I cant find where you tried to say you were from the Philippines.
If you werent so retarded and would stop responding to SRI threads like you sell them then I dont think we would know its you all the time.
So maybe time to think of a new name because this one will be gone soon.
Ghost Rider
Banned
Sounds like a cry for help.
My dyno numbers were higher with the hood closed then it did when it was open, and I have the Cobb SRI.
MAZDA_SPEED
Member
- :
- BLACK MSP
dont get a CAI...save your money and get a TIP or a DV
pictures are worth a million words...cai are worth less SRI>CAI
pictures off vortex, but it will work here as well
CAI
Stock air box
pictures are worth a million words...cai are worth less SRI>CAI
pictures off vortex, but it will work here as well
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Ghost Rider
Banned
Great post Mazda speed!
black_ninja23
Member
- :
- Mazdaspeed 3
so basically, according to that well drawn diagram, don't waste my money on CAI? and instead save it for an upgraded intercooler? (drive2)
MAZDA_SPEED
Member
- :
- BLACK MSP
man, cant you read...it said "good intercooler is intercooling the air"(chair)
jk, its your choice. dont bag on the well drawn diagram. its the only proof we have that SRI is better than a CAI (rofl2)
jk, its your choice. dont bag on the well drawn diagram. its the only proof we have that SRI is better than a CAI (rofl2)
Silver Ecstasy
Member
- :
- 11 MS3 Sport
If you guys really care, we're going to attempt to do some data logging on the Dashhawk soon.
My car completely bone stock.
CWPspeed3 with Cobb SRI.
Mazdaspeedster3 with CAI.
Apparently, they've already done a few races from a dig, and they were dead even. But to solve all this nonsense, I think we're going to take it upon ourselves to log the data and let you guys deal with the myths.
I will most likely end up getting a Cobb SRI, just for the ease of install and maintenance.
My car completely bone stock.
CWPspeed3 with Cobb SRI.
Mazdaspeedster3 with CAI.
Apparently, they've already done a few races from a dig, and they were dead even. But to solve all this nonsense, I think we're going to take it upon ourselves to log the data and let you guys deal with the myths.
I will most likely end up getting a Cobb SRI, just for the ease of install and maintenance.
From the dyno, power output seems a bit smoother with it (The SRI).. but that could just be MAF sensor problems w/ the CAI
I think you guys are missing something here.
According to the Adiabatic Processes equations for a turbo charger and intercooler theory, the intake temperature will not only affect (and amplify) the temperature after the turbo it will affect the temperature after the intercooler, putting hotter air into your engine.
The intake temperature has a big affect on performance. If you are sucking air inside the engine bay you will work your intercooler alot harder resulting in heat soak.
Take a look at the link below:
http://www.stealth316.com/2-turbotemp.htm
Now lets enter some numbers- I used the following:
Intake Temp = 70 degrees
Inlet pressure = 14 psi absolute (assume -.7 loss due to intake/pipe (14.7-0.7))
Outlet pressure = 16 psi
Compressor efficiency = 65
So with this scenario you get a temperature after the turbo of 266 degrees F.
Now lets assume you are getting air from the engine bay that is 100 degrees.
Now you get at temperature after the turbo of 307 degrees.
Is that 41 extra degrees going to heat soak your intercooler faster?? YOU BET.
But it gets worse because even before your intercooler heat soaks you are still getting hotter air at the intake manifold.
If you continue the calculation with the intercooler calcs assuming the following:
Intercooler efficiency = 75
IC pressure loss = 1 psi
Ambient Temp = 70 degrees
With a starting intake temperature of 70 degrees you get a intercooler outlet temp of 119 degrees. With sucking hot engine bay air of 100 degrees you end up with intercooler outlet temperature of 129 degrees.
So right off the bat you gain 10 degrees going into your engine, and this occurs even before your intercooler heat soaks. So this will get worse faster due to quicker heat soak with an intake that is sucking hot engine bay air.
Some other reading if you are interested:
http://www.gnttype.org/techarea/turbo/turboflow.html
http://www.stealth316.com/2-adiabat1.htm
According to the Adiabatic Processes equations for a turbo charger and intercooler theory, the intake temperature will not only affect (and amplify) the temperature after the turbo it will affect the temperature after the intercooler, putting hotter air into your engine.
The intake temperature has a big affect on performance. If you are sucking air inside the engine bay you will work your intercooler alot harder resulting in heat soak.
Take a look at the link below:
http://www.stealth316.com/2-turbotemp.htm
Now lets enter some numbers- I used the following:
Intake Temp = 70 degrees
Inlet pressure = 14 psi absolute (assume -.7 loss due to intake/pipe (14.7-0.7))
Outlet pressure = 16 psi
Compressor efficiency = 65
So with this scenario you get a temperature after the turbo of 266 degrees F.
Now lets assume you are getting air from the engine bay that is 100 degrees.
Now you get at temperature after the turbo of 307 degrees.
Is that 41 extra degrees going to heat soak your intercooler faster?? YOU BET.
But it gets worse because even before your intercooler heat soaks you are still getting hotter air at the intake manifold.
If you continue the calculation with the intercooler calcs assuming the following:
Intercooler efficiency = 75
IC pressure loss = 1 psi
Ambient Temp = 70 degrees
With a starting intake temperature of 70 degrees you get a intercooler outlet temp of 119 degrees. With sucking hot engine bay air of 100 degrees you end up with intercooler outlet temperature of 129 degrees.
So right off the bat you gain 10 degrees going into your engine, and this occurs even before your intercooler heat soaks. So this will get worse faster due to quicker heat soak with an intake that is sucking hot engine bay air.
Some other reading if you are interested:
http://www.gnttype.org/techarea/turbo/turboflow.html
http://www.stealth316.com/2-adiabat1.htm
cobb has an airflow straightener (forget the technical term) that reduces turbulence before the air hits the MAF. that alone could account for the smoother curve. whether or not the air flows any better, if the air hitting the maf from the cai isn't as consistent the ecu isn't as conisistent. I dunno, I've been up since 7am and its after 11pm and I'm tired. I hope this makes sense.......
You're "tired" (beer)
Jk lol
I'm glad I got the chance to see this thread, its old and past my time lol ...
I
There are no vents directing air from the outside to under the hood; except for the one that directs outside air to the intercooler and electronic box. If the air were so cool under the hood, such a vent would not be necessary and Mazda engineers would not have designed same. The intercooler needs such cooler outside air to work at its optimum. All the air under the hood while the car is moving has first been heated by passing through radiator. Remember, the engine is water cooled, not air cooled. The air in the front fender well has not passed through the radiator and is thus cooler. Cooler air is more dense and can atomize more fuel which equals more power. Since the a CAI provides cooler/denser air to the turbo, more is compressed to flow into the intercooler and engine and thus produce more power.
FYI, the Mazdaspeed CAI has an airflow straightener too...
