I have done a decent amount of research on doing this and have it all priced out to build with aluminum tubing with a 4" K&N filter on the end right around $180 for my 2003 CL-S

For a similar price I could buy a name brand full CAI and I am not sure which to go with. I was hoping for some feedback on the idea to run a custom 4" all the way to the throttle body vs buying a pre-made AEM or Injen product.

I also have OBX headers and a full 2.5" exhaust if it matters.

 

I'd go with a 3.5 or 4" custom over a 3" or smaller name brand intake.

Could take Comptech Icebox and just use bigger tubing.

I am running a Airaid U-Build-It 4" intake. They send you a section of plastic tubing and you cut it how you want. No welding required.

 

Same here, running a Airaid 4" with a skunk2 90mm TB

 

....and just as Brian said:

https://acurazine.com/forums/car-par...-s-6mt-944278/

#StepUp

 

Would think anything over 76mm is overkill. Would like to see dyno comparisons.

Comptech is nice, but needs to be modified IMO. If you install it as is, there are points in the tubing where it is restricted to only 2.5". At the least I would replace the crappy silicone couplers and their ribbed for pleasure design.

 

Probably is, got the manifold/tb setup in a trade, figured I use it. That paired up with the headers I got from you should be interesting. Hopefully in May/June I will be able to get tuned.

 

Anxiously awaiting.

I'd be worried about throttle response with such a massive TB. Have you been driving with it? Notice anything?

 

I went ahead and ordered everything to put together a 4" intake minus the filter for a total of $82.73 on ebay. The filter was $25 from an auto parts store, though I plan on buying a large k&n if this works out well.

I am also going to attempt to bypass the VSA throttle body. I understand it requires some resistors to feed the vsa's control unit a constant voltage, fortunately I am good enough with electronics/multimeters/math that it wouldn't be hard to figure out assuming that is all there is to it.

 

Decided against the VSA tb removal after some further reading. It is not worth the inconvenience.

 

I went ahead and did everything, VSA throttle body gone with no lights on the dash, and a 4" aluminum intake. There are noticeable gains in my opinion. I would like to get a more gradual 3 to 4 inch coupler to see if that makes a difference too.

 

Here's a picture of it as a short ram air type intake, it felt quicker than stock but lost a little of its power once the engine warmed up.