How big is the 3V K&N tube?

[Floordford]

Im working on making my own intake tube set up but I want to know how large the inner diameter on the K&N tube is. Mostly for the MAF calibration. If my tube is too big in the sample area I may run lean or throw a CEL. It may be possible to cut the MAF section off the upper lid and integrate it like that.

If you are interested im tossing around the idea of a 3.5" into 4" elbow to 4" tube to 4" into 3.5" reducer. I may keep the stock air box. But if I cut the MAF off the box I can do a 3.5" elbow and do a large round filter. Another idea is to see if its a viable option to put the battery on the other side. I really hate that a Mustang intake manifold wont work. Big manifolds on trucks dont hurt. The 90s 5.0 truck intakes were way oversized and it helped. So the argument of it breathing too well goes right out the window.

 

[SixPonies]

So are you trying to do something like this? I used 3.5:" pipe (cut to about 14" long) and 3.5" 90-degree and straight couplers. I also cut/modified the snorkel coming into the air box to direct more air straight up into the filter (K&N drop-in filter).

 

[Partsman109]

That is an awesome setup SixPonies, very nice job!!

 

[Floordford]

Yes exactly. But I want to do a 4" tube instead of a 3.5". JLT did this with the RAIs and had the most gains over any intake. It may have to do with the way the tube slows air at the outer edge of the moving air column. The larger tube allows the air in the center to move more undisturbed.