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jrsc with cold air intake

i just got the jrsc kit and was wondering if my 65 mm bord throttle-body and my aem cold air intake would still work and clear my fs strut bar
 

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Discussion Starter #3
has any one put a cold air intake on a jrsc if so post pics and tell how you did it
 

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teh tranny killer
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from what i heard cai on the jrsc is no good because it doesnt like having to pull air into the engine, thats why the bbk comes with the svt intake system, better for the s/c design
 

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correct, a CAI on a JRSC is a no no.

The JRSC does NOT like to work for its air, stick with the SVT air box, it has been dyno proven to be better/more efficient.
 

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Yup, the TB will work, you will want to port out the JRSC to match the 65mm TB, it will give you almost another LB of boost. Dont try the CAI, use the SVT air box.
 

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...yea', agreed. I think, generally, the SVT airbox works relatively very well. 'A possible intake alternative: FocusSport Cool-flo. But, I think you get a little bit more of the engine heat, even with the heat shield.
 

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You can use a CAI but i asked oscar jackson himself and he recommended not to and im sure he knows a thing or to. I am currently running a 65mm tb and HIA short ram. I havent ran it with the stock airbox but ive heard it works very well also.
 

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Fins Up!
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any opinions on a custom cold air intake, 3" with a lot less bends than a cold air intake that you buy from a company. I made one for my sc but have yet to get to install it because of a lack of parts. I also have a focus sport cool flow so i'll use the one that works best and post my results.
 

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tls_bmx said:
any opinions on a custom cold air intake, 3" with a lot less bends than a cold air intake that you buy from a company. I made one for my sc but have yet to get to install it because of a lack of parts. I also have a focus sport cool flow so i'll use the one that works best and post my results.
I had thought about making a custom one. Not as long as the AEM one but something to get the intake out of the hot engine bay.
 

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I've been researching which way to go for my JRSC install and think I'm leaning toward the stock svt air box.., it's actually pretty free flowing. Would like to go with my Steeda SRI but, don't want to throw a cel with the heat factor... just cleaned my stock box up to get ready for my install next week.
(Oct.3rd)
 

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What about the volant air box w/ the jrsc. I don't think that would be a bad setup.
 

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Probably a good choice too but, don't want to spend any more $$$ at this point. At some point if I do get a custom tune I can re-think the air intake. Right now I'm still leaning toward the stock SVT set-up... starting install tomorrow...
 

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Cold air is the only good way to go with a roots style blower. Companies like Kenne Bell will void your warrenty on their whipple charger if they know you run a SRI, they say the heat from the engine bay will cause damage... actually more like deto.
 

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Technically, Oscar Jackson recommends SRI's because as previously stated, M45 isn't strong enough to work for its air. SVT airbox is the most highly recommend and Dyno-Proven to yield the highest gains thus far.

HOWEVER, a CAI will give lower IAT's which will yield denser air and more power BUT it has to be free flowing air so as to prevent inhibiting the supercharger.

Solution? A bigger pipe where air is being forced through the tubing.

I'm thinking about making a custom 3" CAI for my JRSC that opens right into the mouth of the front bumper so that air gets pushed through this thing. maybe I'll design some kind of scoop to direct air into the filter.
 

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^^ see after thinking about that...If a N/A zetec can pull air through a CAI just fine, why would a boosted engine have any difficulty? Doesnt make sense to me.
 

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because think about the physics of the situation. The Zetec has negative pressure from the exhaust gas forcing out of the cylinders. When the intake opens, that negative pressure creates a VACUUM that sucks the air right into the engine.

In the case of the M45, the supercharger is actually blocking off the intake manifold so the only air the engine gets is the air coming through the rotors.

Now the rotors themselves aren't creating a vacuum as powerful as the result of an explosion in the engine cylinders. They working by displacing the air that is around them, the rotors just spin around and around. As a result of the small rotors spinning, only a small vacuum is created.

What this is showing is that the M45 simply cannot create a large enough vacuum to suck air all the way up through a restricted CAI tube. Especially a vacuum as large as the engine itself can generate. Just another parasitic feature of forced induction.

Now because work is defined as force times distance, the supercharger then has to do more work to pull the air all the way through the tube which then inhibits the efficiency of the supercharger.

Visually,
Suck air through a 3" straw and suck air through a 10" straw.
Lengthening the straw adds resistance

What I plan to do visually
Suck air through a 3" straw
Suck air through a 10" straw with a larger diameter.
Lengthening the straw adds resistance, increasing diameter decreases resistance.

Using fluid dynamics equations that I'm not going to flood the thread with lol,
or maybe I willl.....
R = (8hL)/(pi)r^4

R resistance
h=fluid viscosity (air in this case)
L=tube length
p=air pressure
r=pipe radius

You can calculate the exact length and diameter needed to have the same resistance as the SRI so that the CAI doesn't restrict airflow anymore than the original SRI by setting the resistances equal to each other.

(8h(L1))/(pi(r1)^4)=(8h(L2))/(pi(r2)^4)
8, h and pi are constant so they go away so it becomes..
(L1)/(r1)^4=(L2)/[(r2)^4]
by isolating r2...
r2=(L2*[(r1^4)/(L1)])^(1/4)
Now say our SRI has a length of 2.5 feet (30 inches) and an inner diameter of 2.5" (radius=d/2=1.75")
And lets say our CAI is 4.5 feet (54 inches) long
r2=(54*[(1.25^4)/(30)])^(1/4)
r2=1.45"
So for a 4.5ft CAI to have the same resistance as a 2.5ft SRI with a 2.5" diameter, you'd need a 2.9" pipe.... SO THERE OSCAR JACKSON :p lol..

Yeah my major is Aerospace Engineering, so what lol....
/end of my longest post ever

EDIT I ACCIDENTALLY SAID 2.5/2 = 1.75. I HAVE CORRECTED THIS, YOU DONT NEED A 4" PIPE, YOU ONLY NEED A 3" PIPE!!!!!!!
 

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...tuche
 

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wow!...Ive already built my CAI for it but I am still waiting on my tune to come in before I can install it. It is 3" inside diameter and only has one 45* bend -I had to relocate the battery to do that. No math formula I just made it the least restrictive I could think, no 90* bends and a really large tube
 
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