94 EX Ram-Air project

[ciVTEC94]

i recently acquired a 94 EX coupe, and i love the car, my goals with it are not to "pimp it out" or to make it a real balls out street racer, but i do my own maintenance when i can and id like to learn some stuff with this car.

whats sparked my interest lately is the air intake system, now i know that it seems very fashionable lately to just rush onto Ebay and pick up some bullshit CAI or S/R, but i can see why people may question the stock intake's position.

now i dont claim to be more qualified to design an engine layout than the good team over in japan, but i see room for improvement. so in my quest for a little bit of learning and some power gains, ive decided i want to try and design and build a Ram-Air system using platic ducting and running an inlet to below the righthand headlamp. Any suggestions in this area would be well taken, and pointing out any faults to my logic would also be appreciated, thanks

[steve8091]

I think you've got some admirable goals - good luck with it. Keep in mind, though, that your biggest flow restrictions (accordingly to Bernoulli's equation)will likely be the filter and the inner surface roughness of the pipe. The second one is all-too-often neglected, but can have substantially more impact than pipe bends.

[Ricochet]

He accidentally double-posted
http://www.automotiveforums.com/vbul...d.php?t=206542

[ciVTEC94]

yea, sorry about that

[spooleffect]

I'll post in this one since there are 33 posts here.

Ram Air can cause a major problem for you though because it only works at specific speeds. If you get a pressure in the Intake Scoop that is higher than what the engine wants to take in, a high pressure area forms at the opening and the outside air goes up and over the scoop instead of going into it.

I'm biased to the stock air-box with a drop in filter or a high performance air-box like Comptech or Mugen.

[ciVTEC94]

i understand your point, but whats the basis for your being biased?

[spooleffect]

Well I'm biased to air-boxes because they work best for filtered intake applications. Im not partial to ram-air obviously, and I don't like exposed filters(CAI and Short Ram) because the filter is always open to the elements and whatever gets slung into the engine bay will be slung into the filter which lessens the filter life and performance. A $30 K&N dropped into the stock airbox will yield the same performance as a $200 intake system plus the filter will last longer and the stock box pulls in cold air without the problem of rubbage flying at your filter.

[SilverY2KCivic]

Typically when people get intakes, it's for the noise factor that it creates. They are better in the sense that they allow increased airflow, but think about the design. You have a metal pipe. It lays in a HOT engine bay. Local ambient temps highly influence any metal nearby. Heat = not so good for power gains.Maybe if the short ram or CAI piping were made out of the same plastic as the stock aorbox, then they might be more worth while. The filter used can also make a big differance as well, as we all know.

[mycivic]

Originally Posted by spooleffect

because the filter is always open to the elements and whatever gets slung into the engine bay will be slung into the filter which lessens the filter life and performance.

I read on another board, some one did this. He had one head light and the right one was a ram intake in place of the other headlight. And while driving, a bird got sucked in according to him. He had a hard time cleaning it.

[ciVTEC94]

yea silver, i was thinking about the metal piping, and i had plans to use plastic anyway, but if i were to use metal i could use a ceramic paint to help dissipate the heat absorbed

[spooleffect]

The metal piping on an Intake is not long enough to transfer its heat into the incoming air though. A regular ol straight intake tube is not a good heat exchanger in the least. This is not a problem that you really need to consider with most engine and bay layouts.

[ciVTEC94]

interesting point, i appriciate the thought, something for me to think about, yet, i still would love to settle the whole bypass valve idea

[spooleffect]

Don't waste your money on a bypass valve. I have never heard of anybodys car engulfing enough water to damage the motor unless it was still running when it became submerged in flood water.

As I said before, a $30 drop in K&N works just as good as a $200 CAI.

[ciVTEC94]

well, i guess my question is how large of diameter would the duct have to be, and how big of a bypass valve do they make?

[spooleffect]

Originally Posted by ciVTEC94

well, i guess my question is how large of diameter would the duct have to be, and how big of a bypass valve do they make?

Can you rephrase this, im not sure of what you are asking?

The bypass vavlve diameter is most likely 3" or 2.5" like most common intake tubing sizes. Not sure if this answered the second part of the question but I can't understand the duct part.