ram air Vs. cold air
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Joined: Nov 2004
Posts: 90
From: utica Mi.
ram air Vs. cold air
i have the ss hood with the stock z28 air intake. i need help deciding on what type of performace intake i should get. i know you dont need to be moving for the cold air to be effective and the ram air is only good after about 30mph but i figure thats where i need more power anyways. im already havin traction problems and im not planing on runnin drag radials or slicks.
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Joined: Sep 2004
Posts: 416
From: Helotes/San Antonio
Re: ram air Vs. cold air
I may get a lot of heat for this one, but!
I have a friend who has a shop with a dyno, and is a very good tuner.
He has ALWAYS seen 10 hp from the LT1 Ram Air setup.
He said it's not the ramming, it's the straight shot that produces the power.
He has swapped CAI's onto ram air cars and lost 10, and put ram air boxes on
non ram air cars and gained 10 hp with the hood up.
I have a friend who has a shop with a dyno, and is a very good tuner.
He has ALWAYS seen 10 hp from the LT1 Ram Air setup.
He said it's not the ramming, it's the straight shot that produces the power.
He has swapped CAI's onto ram air cars and lost 10, and put ram air boxes on
non ram air cars and gained 10 hp with the hood up.
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Joined: Mar 2001
Posts: 2,667
From: SLC, UT
Re: ram air Vs. cold air
Originally Posted by RedLT4Mike
I may get a lot of heat for this one, but!
I have a friend who has a shop with a dyno, and is a very good tuner.
He has ALWAYS seen 10 hp from the LT1 Ram Air setup.
He said it's not the ramming, it's the straight shot that produces the power.
He has swapped CAI's onto ram air cars and lost 10, and put ram air boxes on
non ram air cars and gained 10 hp with the hood up.
I have a friend who has a shop with a dyno, and is a very good tuner.
He has ALWAYS seen 10 hp from the LT1 Ram Air setup.
He said it's not the ramming, it's the straight shot that produces the power.
He has swapped CAI's onto ram air cars and lost 10, and put ram air boxes on
non ram air cars and gained 10 hp with the hood up.
Registered User
Joined: Jun 2004
Posts: 395
From: Bay Area, CA
Re: ram air Vs. cold air
it's the straight shot and cold air that produces horsepower, the "ram-air" effect is a total myth, I'll go into it if you really want me to, but it has to do with the difference between static and dynamic air pressure.
The SS style ram air is however less effective than a simple cold air intake, due to the restrictive pipe bends, and it sitting on top of the intake becoming heatsoaked.
Get a CAI and thank me later.
The SS style ram air is however less effective than a simple cold air intake, due to the restrictive pipe bends, and it sitting on top of the intake becoming heatsoaked.
Get a CAI and thank me later.
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Posts: 827
From: Philly, Pa
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Re: ram air Vs. cold air
"Ram air" is explained quite simply with the principle of "velocity head". If there was no pressure developed by the moving air stream, the pitot tube used to measure air speed on an airplane would not function.
Using the concept of velocity head will show that the maximum pressure gain at 100MPH is about 1% of static pressure, and hence you will see no more than a 1% HP gain - and probably less, due to the inefficient inlet shape of both the WS6 and SS scoops. There is also the issue of boundary layer, which reduces the velocity to near zero at the surface of the hood. In this respect, the frontward location of the WS6 hood scoop would show better results than the SS scoop, simply because the boundary layer grows as you move farther back on the hood.
If you consider the fact that velocity head increases with the square of the speed, a car moving at 50MPh would only see 0.25% increase, and one moving at 150MPH would see a 2.25% increase. If you don't believe in "ram air", ask the NHRA Pro Stock drivers to remove their huge hood scoops. The shape of the opening has been developed with extensive wind tunnel testing to maximize the percent of pressure gain that is "recovered".
There is something to be said, and has been said above, regarding the tortuous path that the air must follow with the stock SS ducting. It will probably offset any velocity head pressure gains with frictional losses. Then there is the issue of heat gain due to the ducting being right on top of the hot engine. Another advantage for the WS6 configuration....... straight and short.
http://cjcfo.fbody.com/members/injun...os/IntakeTrack
Using the concept of velocity head will show that the maximum pressure gain at 100MPH is about 1% of static pressure, and hence you will see no more than a 1% HP gain - and probably less, due to the inefficient inlet shape of both the WS6 and SS scoops. There is also the issue of boundary layer, which reduces the velocity to near zero at the surface of the hood. In this respect, the frontward location of the WS6 hood scoop would show better results than the SS scoop, simply because the boundary layer grows as you move farther back on the hood.
If you consider the fact that velocity head increases with the square of the speed, a car moving at 50MPh would only see 0.25% increase, and one moving at 150MPH would see a 2.25% increase. If you don't believe in "ram air", ask the NHRA Pro Stock drivers to remove their huge hood scoops. The shape of the opening has been developed with extensive wind tunnel testing to maximize the percent of pressure gain that is "recovered".
There is something to be said, and has been said above, regarding the tortuous path that the air must follow with the stock SS ducting. It will probably offset any velocity head pressure gains with frictional losses. Then there is the issue of heat gain due to the ducting being right on top of the hot engine. Another advantage for the WS6 configuration....... straight and short.
http://cjcfo.fbody.com/members/injun...os/IntakeTrack
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Joined: May 2004
Posts: 1,210
Re: ram air Vs. cold air
Originally Posted by Injuneer
"Ram air" is explained quite simply with the principle of "velocity head". If there was no pressure developed by the moving air stream, the pitot tube used to measure air speed on an airplane would not function.
Using the concept of velocity head will show that the maximum pressure gain at 100MPH is about 1% of static pressure, and hence you will see no more than a 1% HP gain - and probably less, due to the inefficient inlet shape of both the WS6 and SS scoops. There is also the issue of boundary layer, which reduces the velocity to near zero at the surface of the hood. In this respect, the frontward location of the WS6 hood scoop would show better results than the SS scoop, simply because the boundary layer grows as you move farther back on the hood.
If you consider the fact that velocity head increases with the square of the speed, a car moving at 50MPh would only see 0.25% increase, and one moving at 150MPH would see a 2.25% increase. If you don't believe in "ram air", ask the NHRA Pro Stock drivers to remove their huge hood scoops. The shape of the opening has been developed with extensive wind tunnel testing to maximize the percent of pressure gain that is "recovered".
There is something to be said, and has been said above, regarding the tortuous path that the air must follow with the stock SS ducting. It will probably offset any velocity head pressure gains with frictional losses. Then there is the issue of heat gain due to the ducting being right on top of the hot engine. Another advantage for the WS6 configuration....... straight and short.
http://cjcfo.fbody.com/members/injun...os/IntakeTrack
Using the concept of velocity head will show that the maximum pressure gain at 100MPH is about 1% of static pressure, and hence you will see no more than a 1% HP gain - and probably less, due to the inefficient inlet shape of both the WS6 and SS scoops. There is also the issue of boundary layer, which reduces the velocity to near zero at the surface of the hood. In this respect, the frontward location of the WS6 hood scoop would show better results than the SS scoop, simply because the boundary layer grows as you move farther back on the hood.
If you consider the fact that velocity head increases with the square of the speed, a car moving at 50MPh would only see 0.25% increase, and one moving at 150MPH would see a 2.25% increase. If you don't believe in "ram air", ask the NHRA Pro Stock drivers to remove their huge hood scoops. The shape of the opening has been developed with extensive wind tunnel testing to maximize the percent of pressure gain that is "recovered".
There is something to be said, and has been said above, regarding the tortuous path that the air must follow with the stock SS ducting. It will probably offset any velocity head pressure gains with frictional losses. Then there is the issue of heat gain due to the ducting being right on top of the hot engine. Another advantage for the WS6 configuration....... straight and short.
http://cjcfo.fbody.com/members/injun...os/IntakeTrack
Good explanation
I heard about that the ram air is more effective for a higher output engines like NHRA drivers.
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Joined: Sep 2003
Posts: 5,907
From: The Wild West
Re: ram air Vs. cold air
I am pretty sure GMHTP had a 5 or so page write up a few months ago too.
You have to figure in cost. $300 or so for the SS intake and fractional increases. $150 for a Lingenfelter one that wont sit on top of a hot engine and you can cut your own lower, larger ram air into the bottom. I'd rather spend the other $150 on a E-WP, rockers, or something that will add another 10rwhp.
-Dustin-
You have to figure in cost. $300 or so for the SS intake and fractional increases. $150 for a Lingenfelter one that wont sit on top of a hot engine and you can cut your own lower, larger ram air into the bottom. I'd rather spend the other $150 on a E-WP, rockers, or something that will add another 10rwhp.
-Dustin-
Last edited by Bersaglieri; Sep 14, 2005 at 08:50 PM.
