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What is the advantage of drilling the holes in the side of the box? Is the intake still restricted, even with the newmission mod? I would think these custom holes would pull in warm/hot air when the car is stopped.
 
It also seems it would drastically hurt the intake pull through the tubes.
 
What is the advantage of drilling the holes in the side of the box? Is the intake still restricted, even with the newmission mod? I would think these custom holes would pull in warm/hot air when the car is stopped.
The holes are in the area behind the headlight, so not exactly in the engine compartment. I drilled holes instead of cutting out a rectangular section so that I could tape up one(or all) if it was too loud or if I felt it hurt anything. I also have the spare airbox, so I can compare the effects of the two setups by driving each over time.

I'm gonna dyno it with the OEM airbox, then swap in the modded one, then do my exhaust.
 
Just saying the truth mate
The other 2 tubes that are attached to the airbox didn't seem to hurt the big tube from depositing large leaves and candy wrappers onto the filter before the new holes were bored. I haven't opened it up again since I modded the mod.

ie. the box was never sealed or relying only on the 3in tube for 100% airflow.

What are you doing for our hobby?
 
The other 2 tubes that are attached to the airbox didn't seem to hurt the big tube from depositing large leaves and candy wrappers onto the filter before the new holes were bored. I haven't opened it up again since I modded the mod.

ie. the box was never sealed or relying only on the 3in tube for 100% airflow.
I see where you're coming from. I guess my concern would not be what is being forced ("rammed") through the newmission tube, but rather that the holes would reduce the amount of vacuum through the factory (cool air) tubes to nearly nothing. Granted, with the large newmisison tube, vacuum would likely be fairly low through the factory tubes already, but with the new holes I'm guessing it might be close to nonexistant.

Reducing the vacuum through the factory tubes and newmission tube and replacing it with air from the engine bay could raise intake temperature while at a stop.
 
Exactly....your hole drilling in the airbox reduces the efficiency of the cold air you gained from the front two inlets and the newmission ram air is what I was saying....now your basically sucking in engine bay air temps instead of near ambient..therefore reducing your maximum effectiveness....[clap][clap]
 
I see where you're coming from. I guess my concern would not be what is being forced ("rammed") through the newmission tube, but rather that the holes would reduce the amount of vacuum through the factory (cool air) tubes to nearly nothing. Granted, with the large newmisison tube, vacuum would likely be fairly low through the factory tubes, but with the new holes I'm guessing it might be close to nonexistant.

Reducing the vacuum through the factory tubes and replacing it with air from the engine bay could raise intake temperature while at a stop.
The holes really don't open to the engine bay. They open to the bumper support behind the headlight. I am running with both triangle block plates removed, so there is a steady supply of air to that area. We're not talking about heatsoaking an intercooler or icing an intake manifold between runs. Our intake manifold is ALWAYS getting heat due to it being right behind the radiator. As I said, if my dyno runs show that I should cover the holes, some speed tape is all I need.
 
Let me just reiterate what I said back on post #82...

It also seems it would drastically hurt the intake pull through the tubes.
referring to the new holes. The air box isn't sealed anymore. Just a bunch of random air being sucked in to a bunch of random openings with opposing forces.
 
The holes really don't open to the engine bay. They open to the bumper support behind the headlight.
You mean the bumper support behind the headlight in the engine bay?

Yes, the holes you drilled open to the engine bay. The Factory intake tubes and the newmission tube don't open to the engine bay. My point is not "heat soak" as you're describing, it is that warm air is being pulled into the box. Before you drilled the holes, air was being pulled from completely outside the engine bay--from the triangle plates (newmission) or from behind the upper grille (factory).

We're not talking about heatsoaking an intercooler or icing an intake manifold between runs.
You're right--we're not.

How will your dyno runs show what those holes are doing for you heat-wise? Are you going to have the hood up and fan blowing? That's not exactly a direct comparison to what's happening when you're idling at a stop or at speeds slow enough where "ram air" is not in play. It's not a direct comparison to what is happening anytime you're driving with the hood down, actually.
 
Ok, at what speed would I need to be traveling for "Ram Air" to actually take place? I've heard in the Mk1's it's over 100mph. Anyone know about the Mk3's? If ram air potential is truly in the near 100 mph range, I've never had it even with the holes closed up. I honestly don't think I've gone over 80 in this car.

But it sounds cool, and not as obnoxious as when running w/o the airbox lid. I'm satisfied. Until any of us can show numbers, all the conjecture in the world won't change the fact that my intake sounds better then OEM

Why?

Because RACECAR
 
Ok, at what speed would I need to be traveling for "Ram Air" to actually take place? I've heard in the Mk1's it's over 100mph. Anyone know about the Mk3's? If ram air potential is truly in the near 100 mph range, I've never had it even with the holes closed up. I honestly don't think I've gone over 80 in this car.

But it sounds cool, and not as obnoxious as when running w/o the airbox lid. I'm satisfied. Until any of us can show numbers, all the conjecture in the world won't change the fact that my intake sounds better then OEM

Why?

Because RACECAR
I don't know about the ram air speed. I just know that I would prefer to pull air from outside the engine bay if I still had the factory airbox installed. To me, that's it's main advantage over most of the aftermarket setups.

Hey, please don't think I'm trying to knock a hole in your theories or mods... I'm just over-analyzing the situation like usual! [screwy] [;)]
 
It's OK. The restriction here, from a strictly Bernoulli stand point, is the MAF and throttle plate. All I've really done is ensure that when the throttle plate is opened wide, the airbox isn't holding anything up. Soon, I'll do something similar with the exhaust. Then that big air pump and it's inherent design will be fully controlling, not an NVH/packaging compromise made by the designers and engineers.
 
I concurr with TiStick based on my own experience.
The first thing I did after putting in a K&N drop-in was to drill 5 half inch holes in the front of the airbox. This proved good to both my SOP dyno and the by the gas mileage goin up just over 1 mpg. If you are moving, there is fresh air coming in there. And I haven't even removed the cover plates yet as there is some flow in already.

I next removed the snorkel and opened more air up there and saw a much smaller improvement.

I'm pretty happy until I get a cat back exhaust.

I guess I could measure the temperature there but I don't feel there is a real need to as this is air entering the area from the front of the car and cooler air will always push back warmer air.
 
It also seems it would drastically hurt the intake pull through the tubes.
By drilling the holes in the airbox..you completely made the ram air hose useless[cheers]
Exactly....your hole drilling in the airbox reduces the efficiency of the cold air you gained from the front two inlets and the newmission ram air is what I was saying....now your basically sucking in engine bay air temps instead of near ambient..therefore reducing your maximum effectiveness....[clap][clap]
Let me just reiterate what I said back on post #82...



referring to the new holes. The air box isn't sealed anymore. Just a bunch of random air being sucked in to a bunch of random openings with opposing forces.

OK, so it's been 4 weeks since I drilled the extra holes. Removed the entire assembly tonight to swap the OEM back in for a trip to the stealership tomorrow. Took pics of how it came out:

Hmm, looks like some dirt/debris impacted on the Outerwears....
Image


Wait a minute, it looks like it's really dirty right over that 3 in tube. But that can't be, I drilled all those extra holes in the box to negate any advantage of ducting air in from below the bumper...
Image


There is a distinctly large circular pattern to this dirty spot on the pre-filter. Must be from all those little holes I drilled...
Image


Sarcasm aside, it looks like I'm still getting plenty of air from the 3" ducting to the drivers bumper triangle.
 
OK, so it's been 4 weeks since I drilled the extra holes. Removed the entire assembly tonight to swap the OEM back in for a trip to the stealership tomorrow. Took pics of how it came out:

Hmm, looks like some dirt/debris impacted on the Outerwears....
Image


Wait a minute, it looks like it's really dirty right over that 3 in tube. But that can't be, I drilled all those extra holes in the box to negate any advantage of ducting air in from below the bumper...
Image


There is a distinctly large circular pattern to this dirty spot on the pre-filter. Must be from all those little holes I drilled...
Image


Sarcasm aside, it looks like I'm still getting plenty of air from the 3" ducting to the drivers bumper triangle.
Regardless of all the extra comments made before... thanks for trying something new, posting pics and write-up... Great to see people getting out of the box with home improvement options.
Do you still plan to dyno? I would love to see your numbers...
That pre-filter got pretty dirty, likely due to the low intake position of the newmission mod... what do you think about capturing air from somewhere else (like higher up). I know the idea behind all this is to obtain ram-air, but I would think the main gain is the simple increase in flow to the air box, you would have to be moving at WOT at a decent clip to obtain any ram air effect..
Anyways, great work and thanks for the beta testing!!
 
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