Opinions on this new Viper VARARAM intake?

joe117

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RussM was an independent tester until his results showed no gain.
They even gave him a free Vipair to test.
 

joe117

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VinR1,
I'm going to say that the NACA duct is an intake port. It was designed as an intake port and in aerospace applications, it is always used as a low drag intake port.

I don't have a masters in Aerospace Engineering from Texas A&M University.

Do you agree with me?
It is an intake, right?
It was never designed to be an exhaust port, right?
It isn't used as an exhaust vent, right?
 

joe117

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Here is a link to a 1945 US Gov report on NACA ducts. This particular link will take you to a part of the report that shows how to design a NACA duct in areas with Thick boundary layers.

It looks easy and it makes for a very efficient intake in areas with thick boundary layer.

The GTS duct could be modded with a plastic, rounded extension of the duct was that would stick on.

By the way, this report has design tables and seems to be a little more down to earth, useable and yet still scientific.


http://naca.larc.nasa.gov/reports/1945/naca-acr-5i20/index.cgi?pagenaca-acr-5i20-p34.gif
 

Russ M

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I would like to get my hands on this Vram, although I am skeptical it seems to have a specific design to the design of the chamber.

If this intake does gain power it is probably from the shape and volume of the chamber.

Anyone have one? In or near LA? I will pay for the dyno testing...
 

KenH

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Looks like it may also benefit from some unshrounding behind the filters, larger (3"?) outlets on the box, and perhaps a less restrictive water separation technique. These are all modifications that have been used with at least some success on the stock viper intake. Curious what they are using for filters though.

To their credit, they have a fair amount of info backing up their claims in relation to the competition on their website (for the Corvette anyway).

http://www.vararam.com/vr1b_comparo01.html


--- Ken
 

joe117

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Russ,
Did you look at the link above?
The part of the research paper about the raised edges of the NACA ducts is very interesting.
It looks like it might be an easy fix for the reverse flow at high speed, that has been reported on the Viper's hood duct.
Properly done, it would look good too.
 

joe117

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Wow Ken,
You're right. They do have quite a bit of test data on real cars under real conditions.
And they have a money back guarantee.
 

joe117

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I read all of it. Here's an interesting quote. I wonder who they are talking about.

"Deflection: This would be a scoop located behind a given area that is fed by a deflecting object or winglet. These are very inefficient due to the loss of energy from the deflecting process and the air turbulence that is generated."

These guys make real air induction systems with real science behind them for real race cars.
I'm very impressed.
 

joe117

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Hey Edmonton,
Before you get VinR1, with his aero masters degree, to write up a good report on Vipair,
you better get it straight with him about the question of the NACA duct being an intake or an exhaust port.

I'm still waiting for his answer.
 

FE 065

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Except the NACA duct, by itself, is too small to adequately supply enough air to even a stock Viper engine at WOT.


Last year I spent hours carefully sealing the extra wide opening of the airbox off to only let NACA duct air into it. It only took a test drive of a few minutes to hear the engine running out of air near 5000rpm.


So the Vararam makes horsepower through the OEM duct design that is poorly positioned/sculpted, siphons air out rather than scooping air in, and is too small anyway to flow enough air for even a stock engine??

You must be registered for see images
 

Russ M

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I dont care what they write on their web site and no one else should either.

Give us actual testing rather than mathamaticaly proven variables. Their are too many variables to calculate on an intake system, and the only way to really know is to test it.

That is why I gave the the Vipair time of day, even though I believed 99.9% of it was BS. I probably spent more time testing the Vipair than its designer spent thinking of it/and building it. He decided that I was out to get him or whatever, I dont care. I wish it worked, honestly I do cause my overall goal is to make more power.

This product MAY work, at least it has much better potential than the Vipair. The reason I say this is because my own attempt at making an intake for the Viper did not include anything like what they made. And the Viper definatly needs some sort of box, I learned that after 6 or so hours on they dyno trying to tune a cold air pipe setup for it.
 

GTS-R 001

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Hey Edmonton,
Before you get VinR1, with his aero masters degree, to write up a good report on Vipair,
you better get it straight with him about the question of the NACA duct being an intake or an exhaust port.

I'm still waiting for his answer.

Joe,

It would be my now overly educated guess on the subject that the NACA duct on the viper was intended by the factory to be an intake, which it probably is until the combined forces of the boundary layer and NACA duct depressurization create a vaccum effect and reverse the flow of air, the exact occurance that the GTSR race car developers noticed at 100-120 mph. I would suggest that if a full vaccum effect is at play at this speed that a great degree of conflict is occurring in the mouth of the NACA duct between 60-100 mph. I am presently working on confirming these numbers but it will take a while. I guess one question would be at what point does more air from the sides of the airbox get drawn into the intake versus the cooler air from NACA duct area, the mix would be 50-50 at 0 mph but NACA duct air would reduce as speed goes up.
 

GTS-R 001

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Except the NACA duct, by itself, is too small to adequately supply enough air to even a stock Viper engine.


Last year I spent hours carefully sealing the extra wide opening of the airbox off to only let NACA duct air into it. It only took a test drive of a few minutes to hear the engine running out of air near 5000rpm.


So the Vararam makes horsepower through the OEM duct design that is poorly positioned/sculpted, siphons air out rather than scooping air in, and is too small anyway to flow enough air for even a stock engine??

You must be registered for see images


Not only is the size of the NACA duct only too small but look at their device, it gets smaller and then gets larger, they are creating an intake that looks like it restricts airflow vs increasing it.
 

Vic

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I remember hearing a Dodge engineer saying he thought the NACA duct did more harm than good, or something to that effect. What his exact words were, I can't remember, but I do remember it was NEGATIVE, concerning the NACA duct.

Regardless what people do to their intake, and regardless of what anyone may manufacture, regardless of their claims, it could be safely said that the NACA duct, uhm, well, s*cks!!!

There was a similar setup for C4 Vettes, that purportedly was good for 1 psi of intake pressure at around 100 mph. If thats true, (and I can't prove it is), then maybe something could be done for any car, using the incident wind to funnel air into the intake plenum.

Like when I am I gonna get the time to do any testing like that? :D
I didn't read each and every page of the Vipair thread, but I gather Russ did a lot of testing, with no measureable results. What I would like to know, is how does any intake perform AT SPEED, when the dynamics of the oncomming air are brought into play. This can only be accurately duplicated out on the open road, or in a wind tunnel. ('scuse me while I let some air out of my wind tunnel)

How would you devise a test for these things? Some kind of barometer in the airbox, and record vacuum and/or pressure throughout the car's speed range? The tests would have to be done quickly, to avoid skewed results due to the change in the air temperature, sun's angle, humidity, etc as the day wears on.
 

ViperJoe

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I had the Vararam on the Z-06 when it first came out (it replaced a Halltech intake system. I was not very impressed with the overall quality of the Vararam at that time. I wound up sending it back. At that point in time they used a foam filter (and claimed that they were making all of the foam intake air filters for the IRL cars). The foam filter was a real homemade looking affair, kind of sandwiched / squished into the bottom (towards the front) of the intake and the "top" cover that fit on top of the foam filter along with a 1" foam gasket. It "looked" like crap with all of that squished out foam sticking out all around the perimeter of the intake box. They had a threaded "T" stud and nut closure that was also IMHO a POS. The owner of the company is a super nice and (I perceived) knowlegable guy who was constantly trying to make the product better and do whatever it took to have a satisfied customer, it just was not going to be me. Another thing about the C5 system was that it is 2 halves of molded plastic that are glued together to form the intake trunking. The seam on the inside had the dried epoxy glue ooozing out with some places that looked like they had no glue applied. This was verified as I took some water and dribbled it in along the seam and it came out on the outside of the seam. I wound up just going el-cheapo with a zip-tied K&N (removing the stock airbox shroud, thereby exposing the air filter)filter.
 

FE 065

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...How would you devise a test for these things? Some kind of barometer in the airbox, and record vacuum and/or pressure throughout the car's speed range? The tests would have to be done quickly, to avoid skewed results due to the change in the air temperature, sun's angle, humidity, etc as the day wears on.

How about using an adjustable throttle-stop ? The throttle stop would only allow the car to do X mph stock in each position when the car is stock, then you could go back out with the Vararam or whatever and see if your mph increases or decreases at the same amount of throttle...

Pre-testing the throttle stop would give you some rough MPH speeds that the stop allows the car to go in each position. Make it simple to set to each stop position, and make sure the adjustments are the same each time.

Vipers are so powerful that it doesn't take much throttle to easily exceed legal speed limits. If you could find a long steep hill to accelerate up while testing it would keep speeds down some, and load the car even more. Testing should be done at least past 1/2 throttle I'd think.
 

FE 065

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I believe the Vararams for Corvettes are picking up incoming air through grills in the front bumper's blunt face, which is a high pressure area of a sort.


That's much different than trying pick air up through the Viper's questionably efficient NACA duct.

Apples and oranges :)
 

KenH

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Except the NACA duct, by itself, is too small to adequately supply enough air to even a stock Viper engine.

I don't have my Viper handy to look at or measure, but it seems like as long as the opening of the NACA duct has at least as much flow area as the two throttle bodies combined, it shouldn't present a major restriction. If it is less, then that could be another wrinkle in the equation.
 

Jay Herbert

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For what it is worth, I asked many of these questions of the owner of VaraRam... even warned him about Viper owners world record Vipair thread :) He said that it was nothing compared to the Vette doubters... I had to chuckle.

Anyway, this is from memory, as it was two or three months ago:

I have been told the Stock Viper Naca Duct is not very efficient, how do you overcome that issue?: Yep,you hear right, the one on a stock Viper is not a good thing, so we are having to design our own that will replace the stock one.

How do you verify your "1/4 mile Guaranty"?: We take a car to the track, and make back to back to back to back runs... swapping the stock intake with ours each run.

How do you verify the HP gain?: The answer was more vague to this one, basically, "We test with a Performance Computer", but never got the specifics of the test conditions. He also commented that the improvements in the 1/4 times verify the HP gains, which if you go to the standard 1/4 mile formula's is true. Looking at the link above they used a "Vericom VC2000 Performance Computer".

Do you use a K&N filter?: No, we manufacture our own. Again, based onthe link above, looks like they make several filters "HP and the Super Street"

It sounded like they had lots of doubters on the Vette world too, but he has been pretty successful at selling intakes to the quick track cars. They also will have a set-up for the Hemi-Rams too if it is not already out. They are the ones that make the neat Velocity stacks to fix the silly Chevy throttle bodies: "Velocity Stack"

OK, that's all I know... continue on ;)
 

VinR1

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Hey Edmonton,
Before you get VinR1, with his aero masters degree, to write up a good report on Vipair,
you better get it straight with him about the question of the NACA duct being an intake or an exhaust port.

I'm still waiting for his answer.
what crawled up your asss dude??

I never said Dodge added the NACA duct as an intake or exit for air. All I said was that based on the duct's position and the simple physics involved, it is very possible that the duct pulls air OUT of the engine compartment instead of providing an inlet like you believe. I dont have a Viper, nor do I have the equipment to test my statements, so Im speaking on observations alone. I wish I could somehow prove it to you but its taken me 7+ years of education and I still dont fully understand myself. I honestly believe the original purpose for the NACA duct mounted on the Viper hood is merely aesthetic with some hope of providing a 'ram air' effect... I dont work for Dodge, nor do I know what they had in mind when designing their hoods... I do know, however, from what Ive learned, that THAT particular duct mounted in THAT location is more likely to PULL air from the engine compartment...

get the pineapple out of your rear and lighten up

on a side note... I believe that if the NACA duct were to be moved closer to the rear edge of the hood 4-6 inches, it would be a VERY effective system and probably add a substantial amount of power... ;)
 

VinR1

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first you say...

VinR1,
I'm going to say that the NACA duct is an intake port. It was designed as an intake port and in aerospace applications, it is always used as a low drag intake port.

I don't have a masters in Aerospace Engineering from Texas A&M University.

Do you agree with me?
It is an intake, right?
It was never designed to be an exhaust port, right?
It isn't used as an exhaust vent, right?
then you say...

might be an easy fix for the reverse flow at high speed, that has been reported on the Viper's hood duct

so which is it?? Ive never said that the duct was to be used as an exhaust port, just that - by accident - by its position, it creates a vacuum and pulls air out of the engine compartment

pick a side before you make enemies
 

FrankTHutchens

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Does this ring a bell?

"I honestly feel that DC's purpose for adding the NACA duct was to provide an outlet for the stream of air coming up from behind the bumper cover... "
 

joe117

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VinR1,
Here's what you said,

"NACA ducts CAN be used as an inlet to provide air and positive pressure, BUT their original and most beneficial purpose is to create a vacuum to remove air..."

"If my race car history serves me correctly, they were originally designed to REMOVE air and pressure from engine compartments"

As I said before, I don't have a masters in Aerospace Engineering from Texas A&M University.

I just want to get this straight.

I say,
The NACA duct was designed as an low drag air intake for aircraft.
Isn't that right?

I say,
The NACA duct is not used by design, as an air exhaust port.
Isn't that right?

If you believe the NACA duct is used by design as an air exhaust port,
please give an example.

Please don't cloud the issue by trying to insult me.
If you know what you are talking about and you can back up your statements, let's hear it.

If you made a mistake or said what you didn't mean, let's hear it.

VinR1,
Please don't wiggle or insult. Just back up what you said, if you can.
 

vipah

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Doesn't everyone realize that the suction from the NACA duct is why the max speed on the Viper is only 80mph?

That is why it stalls at high speeds isn't it?

:D :D :eek: :rolleyes:
 

WCKDVPR

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Here we go again.

We are talking about tenths of a PSI at reasonable track speeds. The original "testing" that vipah, joe117, et al like to refer to was done by RussM who "Hooked up a PSI/vacum guage to the airbox". No way is this ever going to show the differnce we are talking about on that test gauge. Also, who thinks you are going to see ram air gains on a static dyno? As for cold air, you may or may not see this on a static dyno as you do not have the underhood area pressurizeed as you would in a real driving situation - lots of hot airflow through the radiator.

I find it funny that joe117 states above "These guys make real air induction systems with real science behind them for real race cars.
I'm very impressed."

Their fluid dynamics engineer states at 100 mph the pressure increase is 0.176 PSI.

If you are crazy enough to go back to page 33 of the infamous vipair thread, you will see where I did the math and showed the following:

"Bernoulli's equation states along any point on a streamline the relation between Local static pressure (P), density (p) and Velocity (V) is: P/p + (V*V)/2 = constant

Applying this to a moving car, the local air velocity increases due to the car deforming the local streamline as it flows around/over the body. Therefore, we can write the equation for a point at infinity in front of the car and a point at the car and as such the constant equals the same because we are only comparing the velocity and pressure at these two points in the flow. Using Pinf=Pressure Ambient, Vinf=vehicle speed, PA=static pressure near the vehicle surface, and VA=local air speed, the equation becomes: PA/p + (VA*VA)/2 = Pinf/p + (Vinf*Vinf)/2

Looking at a position/opening at the front of the car where local velocity approaches zero (ram air box leading to a throttle body, radiator, etc), this gives us a VA=0, solving for this gives you:
PA/p = Pinf/p + (Vinf*Vinf)/2

If the vehicle is traveling at say 30m/sec (67mph) and using density of air at 1.22 kg/m3 (20 C and 1 atm), solving the equation yields PA - Pinf = (Vinf*Vinf)*p/2 = (30*30)*(1.22/2)= 549N/m2 = 0.08 psi.

Going 60 m/sec (134 mph) yields a positive pressure of 0.32 psi.
Going 90 m/sec (201 mph) yields a positive pressure of 0.72 psi."

If you plug in 100 mph you get 0.173 psi. Joe117, vipah, et al, then slammed this science as incorrect. Now, that it is in print somewhere by a top fluid dynamics guy, it is real science and joe117 is "very impressed". Do you think all people on this board are a bunch of idiots?

Ram air at attainable Viper speeds is real and cold air makes more hp. Deal with it! You can all now go back to the daily rant of debating whether the vipair or the vararam are the right configuration, or how NACA ducts work or whatever, but drop the ram air/cold air debate.

jrkermode is right on when he says "The VaraRam "Ram air in a road car" should be required reading before chiming in on this post." Where was this when the vipair thread was the hot topic?

Have a nice day




:D :D
 

vipah

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WCKDVPR,

I don't think anyone ever debated the fact that ram air or cold air could produce more power. The debate has always been whether a Vipair would provide ram air or cold air to do so.

You may even go back through the original posts and find where ViperMed (I think) stated that this product was not intended to provide ram air, but was intended to provide cooler air. You may then want to read the post where some temperature testing was done and showed NO Delta.

So you can live with theory or fact (test data). I prefer test data to show whether something actually works.

Cheers!

:2tu: :2tu:
 

WCKDVPR

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vipah,

Sorry for the rant. I totally agree test data is better than theory. It is just in this case the test data was done without the appropriate equipment/test conditions to measure the difference the theory predicts. Therefore, I believe we still need to go off of theory.

So, in theory :crazy: , if the vipair was sealed to the intake box, the intake box was sealed as well (no drain holes), and the combination was sealed to the NACA duct (or underside of hood around NACA duct opening), I think the vipair would improve HP in a real world situation. Is it enough HP to warrant buying the device is up to the individual.

Have some of the "claims" be overzealous, I think so. I am just trying to provide some useable information so people can make their own, informed decisions.

Cheers as well!

:2tu:
 

joe117

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WCKDVPR,
I believe you, tenths are possible. I believe that you were right.
I don't believe that any pressure is available from Vipair.
For sure there is not enough to feel.

I believe that in order to get the tenths, the system must be designed properly. After reading their paper on the subject, I believe that the Vararam has some science behind it.

Tenths are available with a properly designed system.
 

GTS-R 001

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Joe,

The Vipair™ routes air from the highest air pressure area on the front of the viper ( right in front of the rad ) directly into the airbox.

This is the same spot that the Vararam people denote as being the proper place and this is where all of their corvette units route the air from.

So why do you feel no pressureis available from Vipair, even though it applies the scientyifical principals that the Vararam guys use on their corvette setup?

You may just have boxed yourself into a corner there joe!
 

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