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Old 31st March 2008, 14:42   #16
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Originally Posted by simplythebest View Post
AFAIK, ram air intake means using your vehicles speed to force more air into the engine.

On sport bikes, the air inlet is an opening below the headlights.

When the bike is at higher speeds, air is forced into the airbox, and increases the pressure of the air (sort of like a very small turbo).

This results in 5-6 bhp increase at higher speeds.
Exactly..guess this whole concept started with the jet engines if i am right.
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Old 31st March 2008, 17:17   #17
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OK, let's crunch some numbers here...

Let's assume I have a 4 cylinder, 1000cc engine.
3000 rpm = 3000 engine cycles / minute : 4 (strokes) x 4 (cylinders) = 3000 times the engine sucks in air.
3000 x 250cc air sucked in = 750 x 1 litre per minute = 750 litres air.

Now let's talk normally aspirated engines; they work with a slight inertia, they suck air at 0,8 bar pressure, so they're not exactly efficient... about 600 litres/minute?
...so we need forced air induction (ram air induction)

However,750 litres air/minute in a 1000cc. engine at 3000 rpm...
750 litres : 60 seconds = 12.5 litres / second, which, in a 40cm2 intake, mean an intake 12.5cm across... gentlemen, that's an air intake 5" across !!!
That intake will allow 1 liter of at 1 m/sec (3.6km/h), so if I want 12.5 litres of air, it'll be... 3.6 x 12.50 = 45 Km/h... 28 mph

Only beyond 45 Km/h will a 5" intake conduit allow forced air... a normal conduit is seldom more than 2" across (internal diametre), which is... one fourth of the original surface, so you'd need to go ... 4 times faster... 45 x 4 = 180 Km/h

Only beyoun 180 Km/h will a 2" conduit actually work as a ram air intake, below that speed it simply looks nice and helps, but intake air will still be under 1 bar pressure.

Am I wrong, or just realistic ???
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Old 31st March 2008, 18:52   #18
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The Scorpio scoop was a dummy Ram intake.. Is it now functional with the M-hawk?
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Old 31st March 2008, 19:03   #19
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Originally Posted by IronWolf View Post
The Scorpio scoop was a dummy Ram intake.. Is it now functional with the M-hawk?
It takes in air for the intercooler.
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Old 31st March 2008, 23:07   #20
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I remember reading an article/test which showed that ram air was not worth it -- and a much greater/easier increase in horsepower could be attained by cooling the intake air by a degree or two.

Cant seem to find this study at the moment though...would be great if someone else managed to.

cya
R
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Old 31st March 2008, 23:23   #21
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is a hood scoop pointless or it ll help getting some cold air into my sri?
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Old 1st April 2008, 00:30   #22
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Quote:
Originally Posted by Vys De BlUR View Post
Hmmmm... but there are a couple of guys who are running Ram air intakes.. And driven a couple of the rides.. Believe me the pick up was real good...
My Galant in the states runs a ram intake, i'll have to hunt around for a pic of the engine bay, but the major differences are the awesome sound, and the feeling of more power on the highways, especially in cool weather...Bay area

It is definately functional, cant tell you how functional, as I've not driven the car before the intake was fitted...
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Old 1st April 2008, 12:51   #23
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Quote:
Originally Posted by DocG View Post
My Galant in the states runs a ram intake, i'll have to hunt around for a pic of the engine bay, but the major differences are the awesome sound, and the feeling of more power on the highways, especially in cool weather...Bay area

It is definately functional, cant tell you how functional, as I've not driven the car before the intake was fitted...
In states the average speed one travels is higher than it's here India, the ram air effect will be noticeable there.

The vehicle has to travel at 50Kmph and above to feel the effect of the system, an that to for long period, on short blasts the time to build up pressure is not there, and the system is use less.
Only good thing about this is the sound of the engine and that gives a sensation of power.
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Old 1st April 2008, 12:55   #24
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Quote:
Originally Posted by paras211 View Post
is a hood scoop pointless or it ll help getting some cold air into my sri?
If you mean on the track, [drag] than there is a definite advantage, but in city driving, it wont help a bit, On expressway though it will be noticeable.
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Old 1st April 2008, 12:59   #25
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I had seen some were a zen which had one of its headlights removed to provide space for Air intake.I think it would be an example of RAM air intake for Indian cars.That car was used for the drag AFAIK.

ram
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