The stock air box has baffles which restrict airflow a bit. Other than that, I don't see any performance advantage for a non-turbo street car. Oh yeah, it does look and sound better, so that is a plus even if it doesn't make the car go any faster.

A larger filter is only a benefit if the engine flows at a higher rate than is efficiently supported by the original filter. The stock-sized panel filter will support roughly 200bhp before it starts to become a restriction. If your engine produces less than 200bhp, then a larger filter doesn't significantly affect performance, but at least it will take a little longer to get dirty.

The stock snorkel is a good source of ambient air. The engine will suck air from the source of least resistance, so it's not such a bad idea to offer it choices if you are not sure about the design of such things.

An optimal intake is pretty big and generally not very practical on a street car. Example:
http://www.mazdatrix.com/faqpics/roadrace/ep01123bb.jpg

The inlet only needs to be sealed if it is designed for ram air compression. Otherwise, I wouldn't worry about it. Even a non-turbo engine will suck in over 200 cubic feet per minute, and at that rate a small leak of slightly hotter air would not matter a hill of beans. The rule of thumb is 1% horsepower per 10degF, which is about 1.5 horsepower for a non-turbo engine.

 

^^^Thanks for that info.

 

That mazdatrix photo is rediculous.

 

I don't know about ridiculous but I did wonder if they had calculated that the engine required that amount of airflow or just put in the largest ducting that would fit and called it good.

 

The Mazda RX-7 Competition Preparation and Service Manual recommends a minimum diameter of 110-120mm. This converts to about 4 1/3 to 4 3/4 inches. While Mazdatrix may have done the math, I wouldn't be surprised if they just rounded up to the closest size available at Home Depot.

The photo probably does look ridiculous to those who have seen nothing but the overpriced rice vendor CAI kits and the home-built knock-offs of them.

 

i think that photo is amazing.

 

wow! looks good man!

 

very nice job, schucks, or whatever auto parts store you have sells a flex pipe, 3'' i think, I got one to put on the passenger side inlet in the bumper were s5 fog lights go, then cut out a big hole to lead it straight to the air intake, just in idea!

 

Sounds like a good plan.

 

You're not wrong. Colder air is better.

 

looks good man, dont let anyone judge your design..i bet half the people on here couldnt even come close to knowing how to do such a thing.

two thumbs up.

 

Unfortunately, the CAI in this thread does not make the ambient air any colder, lol.

 

Thanks Mike.

 

You are right that my CAI doesn't make the ambient air any cooler from the outside of the vehicle, but from inside the engine bay yes. That was my biggest goal. I may take a temp reading from the air box and somewhere in the engine bay and see the difference after i do some hard driving.

HKSpoweredFC3S, thanks man. I know it doesn't look like it took much effort but infact it took a good amount of time to trim and fit everything just right.

 

And what do think that will tell you?

A far better test would be to get temps from your intake manifold with and without the new airbox and see if there's a difference.
I'm guessing there won't be since you have essentially duplicated the stock setup, just using different materials.

Now, before you think I'm just randomly crapping on your parade or being a total hypocrite ( since I've done a similar mod to my car), let me explain myself.

I think it's important to have specific goals in mind when you begin a project like this.
It's also important to be rigorously honest about how fully those goals are realized when you're done.

If you started out thinking the intake temps were going to change or the airflow would increase enough to make a noticeable power difference, then I think you'll have to admit that the project failed.
If you're going to claim success in these areas, be prepared to provide some hard evidence.

On the other hand, if, like me, you started out saying that the whole point was to clean up the engine bay (like yours, my stock airbox had been beaten on by morons) then, as long as the performance isn't degraded, you can claim total success.

People can sneer at ricer intake setups because they make unrealistic and unsupported claims for performance improvement.
If they just said "Hey, it looks nicer than stock and doesn't hurt anything!", then it'd be down to aesthetics and that's hard to argue.

This may all seem like an exercise in semantics but I don't think it is.

 

You are probably right that my intake temps aren't any colder and flow most likely hasn't increased enough to cause a noticable gain. Thats kind of a downer knowing that my project failed in that aspect, but i guess i could live with the cleaner look and the not loss of power.

 

I think it looks great man. Kinda hard to make a true cold air intake on the 2nd gens though see how the space is kinda limited as to were you can put the cone. I am trying to find a way to make a nylon box were my windsheild washer container use to be and guide a monster hose in from a scoop underneath the car into the box were the cone will be hidden.

 

Yea it is. Good luck with yours post pics and what not. I'm gonna hide my washer bottle under my corksport radiator panel i think

 

Did you really think that with an afternoon's labor and a piece of sheetmetal you were going to outdo the Mazda engineers?

What you did accomplish was deleting an ill-conceived prior mod (drilled airbox) with something that looks good, is easily seviceable (no small feat) and didn't adversely impact performance...you should be thrilled.

See?
It's all in how you look at it.

 

I am thrilled, it looks better, changed my exhaust note and gave me a more throaty deeper sound, and it might just be in my head but in this cold weather that we've had it seams to pull a little better in the lower rpm's. But like i said it could be just in my head.

 

It is, but that's OK, you're allowed.