Plenum vs. Cold Air Intake - what's the difference?
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No worries ntlgnt1 - I know you're not looking to pick a fight plus I'm sure we all have better things to do, again I was very critical of the Plenum during R&D back in the day as well so I totally understand your questions and members' critiques. If the thing didn't work, I'd be the first person on the soapbox.
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For those who wish to add a little more zip, the 100% money back guarantee speaks for itself. Thanks...
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For those who wish to add a little more zip, the 100% money back guarantee speaks for itself. Thanks...
But to catch you on your word - could we work out a deal if, say, I buy this item from you for advertised price of $800 and none of my consequent dyno pulls will show any considerable improvement you will allow me to return it?
i just think of it like this.
air acts just like a fluid.
pour fluid into a T and it wont flow as fast or efficient as a Y.
if the internal diameter is the same i would expect gains because the air is flowing faster, spending less time in a hot environment and is less turbulent.
although thats just my guess.
air acts just like a fluid.
pour fluid into a T and it wont flow as fast or efficient as a Y.
if the internal diameter is the same i would expect gains because the air is flowing faster, spending less time in a hot environment and is less turbulent.
although thats just my guess.
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Joined: Aug 2004
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From: Chicagoland
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i just think of it like this.
air acts just like a fluid.
pour fluid into a T and it wont flow as fast or efficient as a Y.
if the internal diameter is the same i would expect gains because the air is flowing faster, spending less time in a hot environment and is less turbulent.
although thats just my guess.
air acts just like a fluid.
pour fluid into a T and it wont flow as fast or efficient as a Y.
if the internal diameter is the same i would expect gains because the air is flowing faster, spending less time in a hot environment and is less turbulent.
although thats just my guess.
Former Vendor
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From: Costa Mesa, California
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As clearly stated, if you purchase the IPD Plenum and are not completely satisfied within 30 days, we will refund your money 100%, period.
I appreciate the minds of engineers
. The Plenum is just one of thousands of products RSS represents.
Thanks, B
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From: ATL
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I've had my IPD/RSS Plenum on for several months, and I won't be taking it off anytime soon.
With a money-back guarantee RSS is standing by this product with full support, and are willing to accept 100% of the risk that you might not like it. Which means they believe in it with all they've got. That's rare, and I respect the heck out of that. I wish all things in life came with such a promise.
If you don't want to try it, don't. It's really that simple. Jeez.
CATTMAN
With a money-back guarantee RSS is standing by this product with full support, and are willing to accept 100% of the risk that you might not like it. Which means they believe in it with all they've got. That's rare, and I respect the heck out of that. I wish all things in life came with such a promise.
If you don't want to try it, don't. It's really that simple. Jeez.
CATTMAN
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I'm not trying to single anyone out but let's come to our senses and just discuss the data.
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From: Chicagoland
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Then as an Engineer you must be familiar with this old quote...“In God We Trust, All Others Bring Data”. That’s what’s been provided here. It’s not a magical pipe and there’s nothing being drawn from the 4th dimension, so definitely no violation of the 1st law of thermodynamics. Gains are proven using the appropriate measurement devices. Last time I checked the SAE recognizes the dynamometer as an appropriate measurement device in measuring torque and power. On Saturday, I witnessed one such measurement device generate data with HP gains.
Can you provide data to backup your claims? When you say "virtually" do you really mean "not statistically significant" based on a p-value >0.05? What measurement device did you use? Did it have the appropriate resolution in conducting your measurements?
Whenever I get into discussions with colleagues regarding data trends, step changes, significance, or just noise, we cover the basis first. So, I would suggest we first talk about the dyno the windshield washer fluid was tested on. Was the equipment within its calibration period? Have there been any recent PM's performed that would adversely affect form, fit, or function of the equipment? If yes, was the equipment revalidated prior to testing? Were there any other factors other than those identified in the testing that could have introduced variability?
I'm not trying to single anyone out but let's comake temperatures on a sunny day driving at 50 mph?e to our senses and just discuss the data.
Can you provide data to backup your claims? When you say "virtually" do you really mean "not statistically significant" based on a p-value >0.05? What measurement device did you use? Did it have the appropriate resolution in conducting your measurements?
Whenever I get into discussions with colleagues regarding data trends, step changes, significance, or just noise, we cover the basis first. So, I would suggest we first talk about the dyno the windshield washer fluid was tested on. Was the equipment within its calibration period? Have there been any recent PM's performed that would adversely affect form, fit, or function of the equipment? If yes, was the equipment revalidated prior to testing? Were there any other factors other than those identified in the testing that could have introduced variability?
I'm not trying to single anyone out but let's comake temperatures on a sunny day driving at 50 mph?e to our senses and just discuss the data.
Correlation does not imply causation. You simply saw a dyno show more power yet jumped to the conclusion that the plenum was the cause for the increase. Great scientific data collection.
There are as many dynos of the plenum that show no gain as there are that show a gain. Please explain how this could possibly be.
I wonder why no one has mentioned the increase in intake temperature using the plenum?
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Correlation does not imply causation. You simply saw a dyno show more power yet jumped to the conclusion that the plenum was the cause for the increase. Great scientific data collection.
There are as many dynos of the plenum that show no gain as there are that show a gain. Please explain how this could possibly be.
I wonder why no one has mentioned the increase in intake temperature using the plenum?
There are as many dynos of the plenum that show no gain as there are that show a gain. Please explain how this could possibly be.
I wonder why no one has mentioned the increase in intake temperature using the plenum?
With regards to your dyno question, did you happen to read my post above regarding measurement devices?
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I'm not jumping btw but glad we can take the first step in talking about the data. Can you identify any other factors in the testing conducted that had more significance than the plenum? Remember we're not conducting a DOE here. This is a simple 1^1.
With regards to your dyno question, did you happen to read my post above regarding measurement devices?
With regards to your dyno question, did you happen to read my post above regarding measurement devices?
Variable that effect dyno results: (not in any particular order)
- Air temperature, pressure and moisture
- Transmission and axle gear oil temperature
- Oil temperature
- Oil viscosity
- Crankcase oil volume
- Coolant temperature
- Fuel temperature (Fuel specific gravity changes)
- Tire size/pressure
- Wheel size/weight
- Force used to strap car to dyno
- Placement of fans
- Transmission gear used for pull
- Accidental or deliberate manipulation of the correction factor (always demand raw data)
- Vehicle weight
- Angle of tires on rollers
- Was the computer reset for the after mod runs?
- Intake temperature
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Not trying to start a dispute on this one (I promise - this thread has gotten a bit out of hand) but the implication of the limit case of your statement is that with infinite flow resistance the pump will happily just keep pumping the same volume. Don't think so. Flow resistance does matter. Unknown to me (in this case) is whether the difference in resistance (between plenums) is just playing at the edges or significant, if at all. The dyno numbers are interesting to me, even with the issue of resetting the ECU which I still doubt would diminish it's value.
Best of all though, I think we're heading to a fresh set of tests given the request for a refundable trial. I'm really interested in seeing the results. If I could get 18-20 hp for $800, I'd be in. Would make the x51 option seem even more, um, extreme.
Best of all though, I think we're heading to a fresh set of tests given the request for a refundable trial. I'm really interested in seeing the results. If I could get 18-20 hp for $800, I'd be in. Would make the x51 option seem even more, um, extreme.
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Forgive me if I'm wrong, but on 997s I believe the X51 kit already includes a larger throttle body and a performance plenum.
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Sorry, I wasn't clear. I was satirically (though badly) citing that the cost of an x51 modification (when ordering the car) costs a lot more per hp than this plenum thingie. If the numbers prove out.
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ah gotcha. Well one of the reasons why I'm considering trying the plenum (aside from the money back guarantee) is that the x51 kit does change the plenum which indicates to me there is room for improvement. I'm just trying to figure out exactly what the improvement really is relative to costs. Would I pay $800 for 20hp? Absolutely. Would I pay $800 for 4hp? Probably not. If I do try the plenum, I will follow Porsches advice and upgrade the throttle body with it.
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I think you just nailed it my friend, that is the exact thing I was explaining to Mr. 1999. Someone understands the concept here and soon enough he will see the windshield fluid in his a$$
