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Discussion Starter · #1 ·
Hey guys. Well I think I'm ready to start working on my MS3. Its an 08.5 with only a few thousand miles on it, so its still pretty new, but I'm ready to jump right in. The only problem is I don't have a lot of cash right now... So I decided to take things one mod at a time and I'm looking for some opinions. I'm ready to buy either a Cobb intake or a new rear engine mount (probably StreetUnit), but I'm only going to get one right now. The other one will come later, probably some time this summer.

So what should it be? Intake or engine mount?

Thanks for the help (and sorry if I am being redundant, the search feature wasn't working).
 

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you won't regret with either one
intake gives you +10 each torque&hp depends on brand, louder stock bov sound (if you like), possibly slightly better mpg.
engine mount will give you much better and solid shifting feel.

those two were my first mods as well and they were worth every penny.
 

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If you are not getting another mod for a few months, I would get the intake. Just so you can enjoy the PSHHT. Realistically the mount should come first, but you won't get as much fun out of it as the intake.

Get a CP-E intake instead.
 

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intake, and shifter bushings since they are only $35. You could also get the corksport motor mount inserts for around $30. They worked for me.
 

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Discussion Starter · #7 ·
[quote author=i love jdm hoes link=topic=138252.msg2988153#msg2988153 date=1236801988]
[quote author=MS3x703 link=topic=138252.msg2987848#msg2987848 date=1236793720]
get the cp-e cai
[/quote]
x2
[/quote]

Eh, I thought about it, but it is a good bit more expensive and I'm working on a limited budget. I'll think about it and see if I can get the funds together.

Hypothetically, if I got the CPE cai, what would you guys recommend about the filter/prefilter set up?
 

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just get an sri and save yourself some money. It doesn't pay to get a cai on a turbo car, because the turbo super heats the air anyway and then the intercooler cools it down.
 

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you fucking retard. i wish i could groan the above post!

this has been beaten to death thousands of times.

the colder the air going into the turbo, the colder it is coming out of the turbo. the colder the air going into the IC, the colder it is coming out of the IC. YES, ITS REALLY THAT FUCKING SIMPLE. why is this so hard to comprehend?

but i agree with dread at the same time. if your limited on funds, pick up a SRI. the gains are similar (CAI has a performance edge over SRI), and cp-e makes a nice one... :) they are most definitely in stock, no wait to get one... so get one now!

i also agree with dread on shifter bushings. those are cheap as balls and really improve shift feeling. after that, get the mount. i would get the intake first because of reasons i love jdm hoes already stated... :)
 

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[quote author=killa cam link=topic=138252.msg2988828#msg2988828 date=1236818064]
you fucking retard. i wish i could groan the above post!

this has been beaten to death thousands of times.

the colder the air going into the turbo, the colder it is coming out of the turbo. the colder the air going into the IC, the colder it is coming out of the IC. YES, ITS REALLY THAT FUCKING SIMPLE. why is this so hard to comprehend?

[/quote]

Because of the ideal gas law. PV=nRT

If you take any given volume of air and compress it under a certain pressure, you are going to get the same temperature, no matter where you start temperature wise. So, if you take a cubic foot of air and compress it under 15.6 psi, youre going to get the same resultant air temp no matter if your origionally started out with 60 degree air, or 90 degree air.

There are only 2 arguements I can see for a CAI making more power on a turbo car:
1. The stock airbox is just plain restrictive, and its the increase in volume the car is able to draw in that gains power. I believe this is usually the case for most turbo applications.

A lot of cars, ie WRX for example don't get much gain of after market intakes until you've upgraded the turbo charger. I think this is where most of the gain in our cars comes in as well... the stock intake has what, a 2 inch diameter inlet? It seemed tiny.

The power curve difference comes in due to the length of the inlet. Here's a good article:
http://www.sportcompactcarweb.com/tech/sccp_0902_2006_subaru_wrx_test_bench/index.html

2. By ingesting cooler air, are you are ingesting denser air, and thus more oxygen... When its compressed, you will still have heated it up with the turbo charger, but you now have a higher count of oxygen molecules. Is this enough of a difference to show up on a dyno? I dunno... I am no chemist and not even sure the validity of this theory.
 

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your wrong there buddy... you must be reading out of cobbs physics book. it's really painful arguing with people who clearly have no idea what they are talking about. a bunch of garage engineers and mechanics in this place! i bet you think it's possible for an air\air intercooler to have 95% efficiency with only a .5psi pressure drop too.

seriously dude, think about what you are saying there. or, consult a professor or something. i got a nifty experiment... why don't you ask a guy in canada with a DH to log his boost, IATs and BATs, and then ask the same from a guy in texas. compare the results.

or, type "pv nrt calculator" into google, and start playing around with the calculator and see what kind of numbers you come up with. don't forget the n variable either! thats an important one. also look up the definition of an ideal gas, (and learn why 'air' is not one).

sounds like you have a lot of homework! i could simply tell you why you are wrong, but i think you would learn more if you did the research for yourself. sorry to be such a dick about it, but it really gets annoying after a while.

i wish other people would say something too, (isn't tvissues a turbo expert?) but they probably know better than to start up this kind of conversation. god knows this forum is full of experts!
 

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Just to backup what Cam is saying, for the week that I had the Nano on my car, the IAT's were 6 degrees hotter than with the Xcel full CAI. No other changes at all.
 

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[quote author=killa cam link=topic=138252.msg2989371#msg2989371 date=1236831017]


your wrong there buddy... you must be reading out of cobbs physics book. it's really painful arguing with people who clearly have no idea what they are talking about. a bunch of garage engineers and mechanics in this place! i bet you think it's possible for an air\air intercooler to have 95% efficiency with only a .5psi pressure drop too.

seriously dude, think about what you are saying there. or, consult a professor or something. i got a nifty experiment... why don't you ask a guy in canada with a DH to log his boost, IATs and BATs, and then ask the same from a guy in texas. compare the results.

or, type "pv nrt calculator" into google, and start playing around with the calculator and see what kind of numbers you come up with. don't forget the n variable either! thats an important one. also look up the definition of an ideal gas, (and learn why 'air' is not one).

sounds like you have a lot of homework! i could simply tell you why you are wrong, but i think you would learn more if you did the research for yourself. sorry to be such a dick about it, but it really gets annoying after a while.

i wish other people would say something too, (isn't tvissues a turbo expert?) but they probably know better than to start up this kind of conversation. god knows this forum is full of experts!
[/quote]

Hey, all I did was explain why people debate it. I didn't claim to know the answer.

If you wanna play with "n" variable, then you have the 2nd "argument" I gave. Hot air is less dense, and thus you are pulling in less oxygen, you're obviously going to make less power. I also said I was no chemist and was not sure the validity of the answer. How much less dense is 90 degree air than 80 degree air? How much less power are you gonna make? Enough to matter? I have no idea.

I also stand by my claims that part of the gain on many cars from intake systems is from the volume of air being ingested. There are many high horsepower turbo cars out there with an open element right next to the motor.
 

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nah dude you came in here saying that shit like it's fact. if you think about it, for only a second, you would realize that the argument is nothing but horse shit. does your car run stronger on cool days vs hot summer days? well according to your post it wouldn't matter, because the turbo heats it up to the same temp no matter what. Wrong!

[quote author=Steve0 link=topic=138252.msg2989418#msg2989418 date=1236832272]
If you wanna play with "n" variable, then you have the 2nd "argument" I gave. Hot air is less dense, and thus you are pulling in less oxygen, you're obviously going to make less power. I also said I was no chemist and was not sure the validity of the answer. [1] How much less dense is 90 degree air than 80 degree air? [2] How much less power are you gonna make? [3] Enough to matter? I have no idea.

I also stand by my claims that part of the gain on many cars from intake systems is from the volume of air being ingested. There are many high horsepower turbo cars out there with an open element right next to the motor.
[/quote]

to answer your questions, you first have to take into account absolute pressure and humidity. both of those will affect air density. if you were to assume 29.92 inches of mercury and 50% relative humidity, [1] the density of 90° air would be 1.145 kg/m^3 and 80° air would be 1.17kg/m^3, a 2.14% change. lets assume mazda strapped the MZR DISI to an engine dyno, and dynoed the car using the standard reference conditions (22.235"hg, 0% RH, and 77°F)(as per SAE J1349) and came up with 263 peak horsepower. if the temp in the air went up to 90° leaving other variables unchanged, [2] you can expect a drop of almost 4 horsepower. but also consider your pressure and humidity... those have an impact as well. So does it matter? [3] I would say yes. Dread would say no. who's to say either of us are right? make up your own mind on that one. I prefer the best solution, some prefer the easiest solution. cp-e now caters to both types :)

and of course, a lot of the gain in power comes from REMOVING THE RESTRICTIONS. anytime you reduce the amount of power needed to move air through the cylinders (pumping losses), you will have more power available to spin the tires. the same theory applies to the exhaust side of the motor. this is probably the bulk of the HP gain, but definitely not the only variable in the equation of making power.
 

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[quote author=dread link=topic=138252.msg2988193#msg2988193 date=1236802741]It doesn't pay to get a cai on a turbo car, because the turbo super heats the air anyway and then the intercooler cools it down.
[/quote]

This is why I hate people trying to up their post count. They don't care about factual info.
 

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[quote author=Ryz link=topic=138252.msg2989942#msg2989942 date=1236870032]
This is why I hate people trying to up their post count. They don't care about factual info.
[/quote]

the sad thing is that he will probably spread that misinformation again, because, well i dunno. it must be because his car runs like shit no matter what the temp is... :)

for further reading check out this .pdf paper from kenne bell. he actually voids your warranty if you use a SRI!

http://www.kennebell.net/techinfo/general-info/HotAirWARNING.pdf

steve-o: look at the pretty pictures that he drew. note the outlet temps of the supercharger with cold air vs. hot air.
 

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"seriously dude, think about what you are saying there. or, consult a professor or something. i got a nifty experiment... why don't you ask a guy in canada with a DH to log his boost, IATs and BATs, and then ask the same from a guy in texas. compare the results."

tr00f, I mean shit, just from the ambient air temp's changing a lot on a daily basis here you can tell that generally your BAT's change proportionately with them. that being said I have an SRI simply because I figured since this car also tends to hate cold weather and it gets brutally cold here that the car might like it to have an SRI instead of CAI, its also easier to change/clean filters, put it back to stock, and it gives almost as much performance benefit for a much cheaper cost.
 

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Back to the OP

I just started modding my Speed3 and I went with the COBB SF Intake first, then the CS inserts, shift knob, bushings, I'm really happy with the results so far. If you knock out the shift knob the amount spent is about $250. So overall I'm not that deep into yet, except the Forge BPV and Rally Armor UR's and the CP-e Towplate that I am waiting on, but yeah, do what you can...and watch out for the mod bug. I told myself intake only when I started :lol:
 

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[quote author=Czar Quanovan link=topic=138252.msg2990492#msg2990492 date=1236885755]
Back to the OP

I just started modding my Speed3 and I went with the COBB SF Intake first, then the CS inserts, shift knob, bushings, I'm really happy with the results so far. If you knock out the shift knob the amount spent is about $250. So overall I'm not that deep into yet, except the Forge BPV and Rally Armor UR's and the CP-e Towplate that I am waiting on, but yeah, do what you can...and watch out for the mod bug. I told myself intake only when I started :lol:
[/quote]

Don't get the inserts....

Spend $29 more and just get the Medieval full dog bone rear mount. You will be much happier with the end result
 
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