Nevermind the why, let's just focus on the how. After some discussion, I gather that the airbox isn't so much restriction until the higher rpms(i.e. I might see 11psi at 4k, but not at 6k). So how much boost would I see at high rpms, and at what rpms specifically?

Steve

P.S. Assume we are not using the stock filter(maybe a K&N or something?), but ARE using a straight through exhaust(3").

 

Every car is going to be different more than likely. I would say with stock i/c and just 3" straight exhaust without cats and only a K&N drop-in...maybe 9psi. Assuming a stock wastegate/turbo as well.

 

i remember with my stock intake, i couldn't get boost over 5k rpm, So i cut the top out where it says 'mazda' and it worked. and i have stock turbo and intercooler with full exhaust. oh and at 10psi

 

err, could you clarify that post a bit please? You got 10 psi after you cut the top out of the box I'm assuming, what did you get before? It's the before I'm interested in. Thanks!

Steve

 

http://www.autospeed.com/cms/article.html?&A=0629


Read that if you really want to learn about intakes.

James