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ram air + turbo

Old Dec 15, 2009 | 05:00 AM
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ram air + turbo

with a full turbo set up, would there be any benefit of having the racing beat air duct?

would that fit?

if it did fit, would it be stealing too much of the intercooler air?

is there even a point to getting ram air with a turbo?

been researching all night, what are your opionions??!
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Old Dec 15, 2009 | 06:39 AM
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I like my RB Ram air in my NA, but I feel unnecessary in a turbo setup and as you cite it may rob your intercooler.
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Old Dec 15, 2009 | 06:55 AM
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you also would have to retune because now your input air in is coming in faster/slower/less evenly/more evenly.
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Old Dec 15, 2009 | 10:27 AM
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The RB duct makes little or no difference to the tune on a turbo car and will block your intercooler.
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Old Dec 15, 2009 | 10:46 AM
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Well, at 60 mph, you can generate like 430 pascals! That's like 0.4% gain!
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Old Dec 15, 2009 | 03:29 PM
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Originally Posted by MazdaManiac
The RB duct makes little or no difference to the tune on a turbo car and will block your intercooler.
i've read that it can make the turbo work not as hard for the same boost

but if it blocks the intercooler by that much, ends up amounting to nothing.
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Old Dec 15, 2009 | 03:30 PM
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Originally Posted by always.anthony
i've read that it can make the turbo work not as hard for the same boost
where did you read that?

if you go FI, just use an AEM intake.
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Old Dec 15, 2009 | 03:32 PM
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Should re-route your intake to your roof, then get a big ram air scoop fed from 2 PVC pipes near your hood washers.
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Old Dec 15, 2009 | 03:52 PM
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Originally Posted by Jedi54
where did you read that?

if you go FI, just use an AEM intake.
"
You allow the turbo to do less work for the same manifold pressure, and thus get more effeciency. It is especially helpful if the turbo is working at its limits.

For example suppose your turbo is most efficient at a pressure ratio of 2.7:1. The pressure ratio is the ratio of the outlet pressure divided by the inlet pressure.
Lets suppose on a given day absolute air pressure is 12.5 psi. If you run the turbo at its ideal effeciency, you get a max boost of 12.5 x 2.7 = 33.75 psi.

Now you add 1 psi ram boost to that same setup, your inlet pressure is now 13.5 psi, so your max boost becomes 13.5 x 2.7 = 36.45 psi.

You gained 2.7 psi manifold pressure by adding 1 psi of ram boost!

Larry"

doesn't the aem also block the intercooler a little bit?

Last edited by always.anthony; Dec 15, 2009 at 03:57 PM.
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Old Dec 15, 2009 | 05:38 PM
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Interesting theory .
But yes , the ram air duct will block the intercooler .
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Old Dec 15, 2009 | 05:52 PM
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Now how fast would you need to go to generate 1 psi of ram air boost? Also, are you going to retune your boost controller to up your gage boost as you generate the ram air boost? How much horsepower or heat are you putting into the charge as you depart the 1 psi ram boost speed? From a dig, you'll be at a P/R of 2.916.

I know dynamic pressure is calculated as p = .5*rho*v² where p is in pascals, rho is density in kg/m³ and v is velocity in m/s. The density of air at sea level is about 1.21 kg/m³. So the dynamic pressure of a gas is 1 psi at 240 miles per hour. Now, is that the right pressure calc to use? I don't remember. And does it account for any funneling effect? No.

Ram air is a sweet affect when you are a jet plane.

Last edited by maxxdamigz; Dec 15, 2009 at 06:07 PM.
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Old Dec 15, 2009 | 07:00 PM
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Originally Posted by tubingchamp
Should re-route your intake to your roof, then get a big ram air scoop fed from 2 PVC pipes near your hood washers.
Or even better build a custom manifold, that mounts the turbo a little above the hood in the direction of oncoming air..............................Problem Solved
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Old Dec 15, 2009 | 07:09 PM
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Originally Posted by Derex'8
Or even better build a custom manifold, that mounts the turbo a little above the hood in the direction of oncoming air..............................Problem Solved
My answer was sarcastic and ricey, your idea would actually work.
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Old Dec 15, 2009 | 07:35 PM
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Originally Posted by always.anthony
"
doesn't the aem also block the intercooler a little bit?
Not at all. The Filter sits behind the intercooler
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Old Dec 16, 2009 | 07:20 AM
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Huh? There ain't that much room behind the front bumper. Does not compute (in my noggin' anyway).

Originally Posted by gregs
Not at all. The Filter sits behind the intercooler
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Old Dec 16, 2009 | 08:32 AM
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Sitting behind anything pretty much negates "ram air." Not that "ram air" does much.
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Old Dec 16, 2009 | 11:54 AM
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Originally Posted by Huey52
Huh? There ain't that much room behind the front bumper. Does not compute (in my noggin' anyway).
you tilt the intercooler forward and the aem intake has room to fit between the intercooler and the ac condenser.

For the purpose of turbo, ram air does not really do much aside from intake temps. Still the air heats up going to the turbo. Any ram air pressure would probably be negated from the air filter.
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Old Dec 16, 2009 | 12:00 PM
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Ah, thanks. Sometimes I think too 2-dimensionally.

Originally Posted by NgoRX8
you tilt the intercooler forward and the aem intake has room to fit between the intercooler and the ac condenser.

For the purpose of turbo, ram air does not really do much aside from intake temps. Still the air heats up going to the turbo. Any ram air pressure would probably be negated from the air filter.
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Old Dec 18, 2009 | 12:15 AM
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just planning out before i take the big steps into turbo, tilting the fmic would affect air flow / cooling efficiency though right?
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Old Dec 18, 2009 | 06:13 AM
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^ by the IC fins not being directly in-line with the airflow a slight drop in efficiency, but I would not think enough to be concerned about. Fluids are pretty good at finding their way. Note that the radiator and a/c condensor are also angled [back] a bit.
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Old Dec 22, 2009 | 05:41 AM
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which come first the ac condenser or radiator?

and if ram air did help, i'd prob go with something like this

http://www.yourhotcar.com/prod/Carbo...ont_Bumper/86/
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Old Dec 22, 2009 | 06:41 AM
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^ the a/c condenser is closer to the front.

btw: my very first mod was a [Mazda] protective screen over the lower half of my condenser to preclude rock strikes. Racing Beat makes a nice a/c screen and I have their oil cooler screens as well.
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Old Dec 22, 2009 | 03:50 PM
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i am on my 2nd a/c condenser due to a very large rock.

i should have had screens put in first thing. i have screens now, mind you.
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Old Dec 22, 2009 | 05:55 PM
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Ram air is a myth. You have to be going over 120mph to get any type of supercharging effect which would be slight at best. Cold air induction is another story. That's why you have cowl induction or cold air ducted from fenders.
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Old Dec 23, 2009 | 06:20 AM
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I knew there was a reason I was compelled to commute at 125 mph.
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