I was wondering, I have only K&n filters on the stock intake pipes and would it be worth the investment to get the more expensive intakes, and if so which setup would you recommend?

 

depends.. if you want if you want bling go hks rs intakes or greddy intakes.. if you want to free up intake go cheap bastard.. k&n are good filters btw.

 

I doubt you'd get any gains whatsoever. The K&N's flow really well, and the big thing they filter very well too. Some of the Japanese filter setups use dry foam filters - these let a LOT of crap through. A good filter is VERY important for long turbo and engine life.

Dale

 

The stock pipes do create turbulence, but as far as performance gains go it won't be worth while to buy hard pipes to smooth out the airflow. Plus K&N flows as well as most anyother filter will.

 

Just get some hard pipes for the K&N filters and you will have the same if not better performance than the more expensive intake kits.

 

If you're after performance (not bling) save your money and just modify the duckwork in FRONT of the air box. The stock duckwork create serious airflow restriction, particularly at high RPM's.

Check out this thread: https://www.rx7club.com/forum/showthread.php?t=347603

 

Indeed they do. I flow tested the K&N in a stock FD box using laboratory equipment. The test compared the K&N against the stock and standard Fram filters. The K&N resulted in about 50% LESS pressure drop at any give flow relative to the other filters.

Additionally, testing indicates and supports the conclusion that the stock air box is adequate so long as you mod it to get MORE COLD AIR into it.

 

but they are only better flow under dirty condition compared to foam filters... but believe me I am all for k&n stlye filter because you have to think about it if you drive the car the filters will get dirty.

 

Someone posted a test in another section recently that showed the K&N flowed best but the flow performance dropped off quickly as they got dirty:
https://www.rx7club.com/showthread.php?t=386376

-Max

 

Thanks a lot for the info, I was going to do the stock airbox mod i saw here with the ductwork to the front bumper, but i dont have the stock airbox. I do HVAC too so it would be one of the easier do it yourself mods for me. So i guess my best bet would be to recharge the K&Ns and call it a day.