i'd like to see your input to this makenzie. please, enlighten us.

 

I'm sorry but your car is not modern...and increasing the capacity of the filter box will have ZERO effect on performance.

I don't know where you bought your car from, but the factory intakes on all 7 of my RX-7s have ALWAYS sucked air from in front of the coolers.

Not as much as a propper cold air pipe, and not any more than the stock intake assembly with a good filter.

 

Go back and read. I never said that the stock assembly couldn't be improved. I said they're going about it wrong. Building another airbox is a total waste of time and resources and it's a hinderence on airflow.

 

You would have to have a duct or something, go look behind your headlight.

Aluminum conducts heat quite well... I would think you would want something that doesnt.

 

ok that is wrong. please stop posting stuff like this.

go put some T25's on your TII

 

glad you could share that wonderful information with us.

Anything added to the intake system that either allows air to expand or causes to to change direction abruptly causes turbulance and is nothing but a restriction. Why do you t hink people use large radius, smooth mandrel bends for everything? They're pretty?

You're not honestly going to tell me that a series of bends, an airbox with a filter in it, then another series of bends connecting to the intake/turbo is going to be less restrictive than a near straight pipe right off the turbo or dynamic chamber leading to fresh air, are you?

 

still waiting on your reply



edit: wait, dont you have an NA?

 

-lets look at the whole picture shall we?
in my civic, when the car is moving, or has been, the airbox is quite cold due to the large volume of air that it is in contact with. i know if it were to sit in traffic for a while, it'd get quite warm... but that'd be the least of that cars concerns..

-yes yes, i know alluminum transfers heat quite well, i wasnt thinking about how other people would design an airbox.. oh well.

 

apparently you forgot to do some reading...

I have both...not that owning a TII would be the only way to have any kind of common sense about this.

 

I assumed when you said that "boxes are not designed around noise reduction" you were referring to cars in general. Also, please point out where I said that increasing capacity would increase performance. I said that it would decrease noise.

The factory intake is above the oil cooler, but only in front of the other two by a few inches. Also, dont forget that the factory intake sits over the radiator shroud, and partially ON TOP of the radiator. That might just have a SLIGHTLY negative effect on that "cold air" it is supposedly drawing in.

Not true, these cold air boxes dont suck hot air from around the radiator, and arent made up of plastic tubing that recieves direct heat from the cooling system.

OK, lets see, I think it was back in middle school when I first learned that heat causes air to expand, and removal of heat does the opposite. That would mean that the entire engine bay is a restriction because it is hot, and a cold air box would not be a restriction because it is a heat barrier.

Regarding an abrupt change in direction, where is that coming from? The air that a cone filter sucks in is around its circumference, and the air in the box has very little, if any velocity that is not generated by the vacuum from the intake. This would mean that a cold air intake would be more restrictive under this rule, unless it were facing directly into the incoming air, in which case it would still be forced to turn 90 degrees to enter the engine bay.

The difference would not be as drastic as the difference between a cold air system and the stock system, or a cold air system and an open filter in the engine bay.

My set up will ultimately have a CAI. I am not saying that the CAI isnt better than a cold air box. Makenzie is 100% right that it is the best reasonable setup for power, but the cold air box is better than he makes it out to be. It is a step up from the factory intake, and much better than leaving an open filter in the hot bay. For people who cannot be bothered to relocate the washer fluid bottle, or cut holes in their cars, it is a good, worthwhile option. As far as dyno results, my cold air box will be extremely crude so that it doesent permanently alter the engine bay, but I will test with one to show that it does make a difference. The results will be more drastic than your average car, because the baseline will be much higher than stock. All I care to do is show that it makes a difference over stock, and unshielded setups.

 

I have seen and documented differences from open cone to a cold air intake.

On my GTP, I saw a 32* difference in temperature from open cone in a hot, supercharged engine bay, to a properly sealed cold air intake box, with an open draw from a fender sealed from engine bay heat and free to draw air from the outside.

This temperature difference changed my knock retard (spark retard) from 5.2* to 0* This is a change of nearly 15* of timing, which is approximately 20 HP in that application.

The concepts in the FC are no different.

edit: By cold air intake, I mean a cold air box sealed from engine bay heat.

What is often referred to here as a "Cold (or cool) air intake" is actually a Fenderwell Intake.

 

makenzie, please try to prove everyone wrong again.

 

It was simply added...no implication.

Plastic isn't a very good conductor of energy in any form...the interior of the ductwork is rather uneffected by being near the radiator. Also, the snorkel pulls air from in front of the coolers...no matter how much you'd like it to be behind them.

http://www.somertoncarimporters.com/...gine%20bay.jpg

Neither does the stocker.

No, they're typically made of metal...a far superior conductor of energy.

Making the airbox a part of a sealed intake system makes the entire intake system subject to it's turbulance. The effect may be minimal, but a straight pipe fed by cool air would be far less effected.

See above...

(misread that, sorry)
Of course not...that's been covered already. The point is that the box idea is going to have an effect on the car's abillity to breath and the least restrictive method (a straight pipe fed by cool air) is going to be able to supply the engine with more air at cooler temperatures.

Obviously, but the difference between going through some misguided effort to rebuild an airbox vs a propper cold air intake is what's being discussed.

I could care less whether you think I'm right or not...I'm not out to prove anyone here is wrong and if that's what you think I'm doing you've missed a lot of reading. Rebuilding the airbox is a waste of time. I never said some of these ideas aren't superior to the stock box in one way or another. What I did say is that it's not very wise to spend the resources and time in building the box when you can achieve superior results with less time, money, and effort involved and travel down a proven road while doing it. Aftermarket boxes aren't available for very many cars because there's simply no point.

 

its not about being right or wrong. makenzie has his good points- some air boxes dont do too much..

has anyone tried to tune an intake for the rotary? i hear the engine has alot of strong pressure waves that i'm sure can be taken advantage of! (thinking along the lines of AEM's V2 intake)

Keep the pics up! its great to see all of these interesting ideas!

 

You just can't admit being wrong can you makenzie, it makes people feel good to customize their vehicle no matter what part they are customizing. If it takes longer, or wastes time why should you care?

 

There's not much to tune. Everything in front of the throttle body just has to be as free-flowing as possible.

Because I'm not. Sorry.

Perfectly ok, but that's no excuse to not understand superior ways to approach things.

 

running the stock airbox is not "superior"

 

Feel free to point out where I said that running the stock airbox (with a drop-in) was superior to anything but an open element in the bay.

 

LESS TYPING MORE PICTURES! DAMN!

Oh, and I will post mine later, I made it purdy and now am in love with Aluminum Tape!

 

how do you figure theres not much to tune?? its kinda like saying that theres no difference in a short air intake vs a longer cold air intake (sides if its warm air, or cold), and that intake runner lengh doesnt do jack..... i know for a piston engine, it makes quite a difference.. http://www.aempower.com/V2.htm the the quickest explination...

 

I am in fact discussing building an airbox. The setup I designed and built is made of 1/4" thermally insulated polycarbonate, cut and adjusted in a manner which keeps any gaps which would allow engine bay heat to the cone filter inside to a maximum of 1/4"

here is a picture with the lid off-



Lid on





This is not dissimliar from what was previously shown on the thread. It is simply made of better materials with an eye for sealing it from engine bay heat. The filter is still in the engine bay, it is simply shrouded by this box. The design of the box allows it to "scoop" air from the hood gap, as well as from behind the headlight and the inner fender. This is not intended as a "Ram Air" feature, but rather to evacuate any ambient heat brought about by the engine heat.

It does work, I have emperical evidence, and if you'd like I can post the scans from my fuel management system interface software showing the temperature drop, and increased available timing.

My FC will have a similiar setup ducting fender and bumper air into a similiar cone. I have IAT sensors on the LS1, and I'll take open cone vs. custom air box temperatures again, as well as comparing maximum commanded (and available) timing.

I'm not arguing that a half *** box is going to be outperformed by a fenderwell intake, rather that a properly designed box will perform within the margin of testing error of a "cold air intake"

We're done now.

 

Dynamic tuning happens after the throttle body (stuff like plenum capacity and runner length and what not). The only thing that needs to be done before the throttle body is to ensure that the intake path is as free flowing as possible, with as much ambient air as possible.

You, sir, are simply not reading.

 

Perhaps you shall enlighten me?

You have stated that the stock airbox is not a restriction, then stated a cold air intake will net you gains, but an intake box will not. This is neither logical or true.

A temperature drop of 30* is very significant. Assuming proper fueling, this will allow more timing as cooler air better resists detonation because of lower cylinder temperatures, and thus more HP.

A denser air charge also allows more fuel to be burned, which will also allow more power to be extracted.

As always there are more variables here, but throughout this thread you've been generalizing dramatically, and some of the assumptions I've seen made are untested or simply flat out wrong.

Perhaps you've failed to make the intent of your statements clear.

edit: A couple examples:

Assuming their box is nearly as efficient as mine, a 30* drop in temperature will net a HP gain.

Wrong again. First of all, race environments do seal the filter from engine bay heat to gain HP. When you're in an environment where 3 HP can win or lose, you do everything you can to make that HP up. Not to mention the extreme heat output by a racing engine and the effects that has on engine bay temperature.

If you are under the belief that NVH (noise, vibration and harshness) were not a top priority in the design of the stock intake, you are sadly mistaken.

See first time you were wrong.

I do agree that a POS hack job intake will do a poor job of insulating, no doubt.

 

No sir. I stated that an aftermarket box was a waste of time, that the stock box is not the most restrive portion of the stock intake (not even near the top of the list, actually), and that a straight pipe fed by ambient air will be superior to all else.

However, I do feel that the stock box, with a good filter, will be superior to most of the concoctions we'll see here.

...who stated otherwise?

...who stated otherwise?

I think I've been pretty clear...it's hard to be unclear with "and that a straight pipe fed by ambient air will be superior to all else."

 

Let's see some emperical data that the straight pipe will outperform the cold air box. In testing a fenderwell intake in my car, I saw less then 1* of air temperature change, which is well withing margin of error for testing.

In regard to where you stated otherwise. Read my edited post.