Cai for 86 rx7 na?
 

Will a cai on my 86 rx7 na (srteet-ported) improve my performance? I've read so much for and against on this site, my head is spinning. I don't know what to believe, anybody have any fact's?

If you are running the stock airbox setup than you wont see any difference. IMO the factory setup with a K&N stock fitting filter is the best way to go. It gets cold air from the front center of the hood to bumper.

If you have some kind of short intake with the filter inside the very hot engine bay you are loosing HP. sucking up hot under hood air will lower your performance no matter that filter you have on it.

In short the CAI will not make any difference and is a waste of money when you can spend 200 bucks on something else and make more power.

An aftermarket intake is only a worthwhile modification on the turbo rx7s. Save your money and invest in a quality exhaust system like Borla, Racing Beat, or Corksport to name a few..

When it comes to an intake system... I advise that this is something that one must experience on their own. Custom build your own, if you're not pleased with the stock intake. I have a cone filter, and a custom air duct from the front bumper to the cone filter, and plan to box it off. I have a modified 13BT, though. I've seen temp reductions... But I do not consider it to be a "cold air intake".

https://www.rx7club.com/2nd-generation-specific-1986-1992-17/few-good-links-i-found-755247/

check out the first two links they have flow charts of intakes etc. the mazda isnt all that great...

Flow of box with slightly dirty filter: 72 cfm

Flow of box without filter: 111 cfm

What quantity of air does a streetported 13B require throughout it's rev range?

Another thing to keep in mind is that those flow numbers are at a relatively low pressure differential.

As some have already stated, on an NA engine, the difference won't be noticeable. If built incorrectly, it can actually increase intake temps.

If you build one the right way, it's in my personal opinion that airflow will be smoothed out versus the stock air-box. I feel the air has to change direction too many times in the stock setup, and it causes turbulence. Does this matter in an NA? Doubtful. But it can also clean up the engine bay a bit, sound more aggressive, and it can be a fun project.

But like I said, ^^That applies so long as you do it "right" (not just slapping a cone filter on the AFM and calling it good).