I've been building air intake systems and so far I'm using pipes with 2"-3.5" in diameter although I feel that it's not truly using its full potential. What do you guys recommend for my 2JZ-GE 3.0L engine's intake pipe diameter? I've read that a 2.5L engine should use 2.75" diameter. The current setup gives me great low and high rpms but not so much the middle. Has great pull too which really puts you in the seat. Although it gets a little slower from 45-60 then goes back up again. Also the type of material suggestions are also appreciated.

*Picture removed because it doesn't show the entire intake*

 

did you seriously make a T of your factory intake to run two filters?

 

It may seem like a T from the picture but it's not. Even though you're face palming I've got performance gains so your comment is close to useless because I stated that I've noticed gains in the thread.

 

ok then what is connecting them in this pic, a Y? where you heat wrapped it... why did you heat wrap the intake btw its not going to see a lot of heat even with your "splice" and it isnt really gonna make that piping cooler. all you really doing is forcing more air in and while that CAN improve performance its unlikely here as your just jamming double the airflow into the same size piping then to the MAF then into the stock ports so i would be shocked if you dont get MAF or airflow sensor codes eventually

ok then prove it.... show me the performance gains and i dont mean the OLD lying butt dyno

IMHO that adds as much performance as those ebay lights add output

 

I'm unable to post my entire reply, I will message you instead.

 

I think a little bigger before the maf but it's important to keep the same diameter past maf into throttle body. I've gone for a 3.5" straight pipe from the maf with a big cone air k&n filter. Straight stainless pipe gives angry sound. Distinct straight 6 jap engine. Nothing like bmw etc. 2jz will love a big filter. They require a lot of air Espicially mid to high rpm. I got a bigger air filter an noticed gains immediately. Although. If you have your filter under bonnet you will notice sluggishness in traffic where engine bay becomes hot from cooling fan. I attached a flexible pipe to my induction kit an pushed down back of headlight into the wing compartment. But noticed this killed a lot of the sound