I didn’t originally want a intake since the gain is so minimal, but after getting my exhaust I was curious of how a intake would make the car sound as well.

I may eventually get a legit intake tube such as the fsport one, but in the meantime I removed the stock resonator and plugged it to see if there was any difference. From looking at after market tubes compared to stock. The biggest difference was the resonator box on the intake tube.

I got a pvc plug that fit perfectly from Home Depot and plugged the hole after removing the resonator. I reset the ecu and went for a drive. I didn’t really noticed any sound change from having the resonator box, at any rpm. Not sure if I was imagining it but it seemed to make my tanabe exhaust drone more.

The stock intake tube is surprising smooth inside. There is only about 1.5 inches of ripples at one end. The rest even though outside shows grooves, the surface inside is smooth. So not sure how getting a intake pipe such as fsport or joe z really makes a huge difference from just removing and plugging the resonator. I’d also rather have plastic then aluminum also, as it’s a little less prone to heat soak.

i know cutting and smoothing the lower box to emulate the fsport box will gain sound, and I may just do it when I’m bored.

any one else try what I have done? And what were your thoughts? I may also try the plug the inlet where the valve vents into the intake tube, and run a breather filter on the valve cover as well.

Well I decided to just design and build my own intake. I used diameter piping closer to oem as my goal was to just get better throttle response, and I got it. Hp from all after market intake tubes are around 5hp, and I’m pretty sure I got that with mine without a dyno test.

I may be offering my kit to anyone that wants to purchase. Aluminum piping would be cheaper and carbon fiber would be pricier obviously.... aluminum would work the same and carbon fiber would on have a benefit of slight less heat.

With my original test of the resonator box plugged on original rubber pipe I really didn’t notice a great sound increase, but I did get slightly better throttle response.

With my custom intake I got the best throttle response and a slight throaty sound. I would say day and night difference being that the pipe is now straight thru and solid, not rubber with some grooves like oem.

So a hard pipe intake is worth it, for feel and response even though hp gain is minimal. I notice and feel the pedal more as I have a manual IS250. Any change in throttle response is more noticeable as you feather the gas and clutch while driving manual.



temperature even after driving hard for a half hour is cool to touch. A aluminum pipe would be too hot to touch. I even checked temperature with a laser reader.


I got a cel due to lean condition from a coupler not tightened hard enough... So while I had the intake I made off before retightening , I wanted to check/test the oem rubber pipe again but with the vacuum fitting plugged and the valve cover venting to atmosphere like the intake I made. The result of this was same throttle response as having only the resonator box plugged. No gain in feel... The problem with oem piping is that it’s soft rubber and flexes. So throttle response lacks compared to having a solid hard pipe.

i prefer venting the valve cover to atmosphere as it didn’t seem to gain or decrease performance from feel I can tell you. However there are other benefits you can read online on your own. And risk factors as another member explained in this thread. I would gladly take the benefits, as the risks can be avoided from proper maintenance.