MAF housing inside diameter?

[07misanored]

Hey guys,

Curiously looking into designing my own intake as I personally find current market offerings a bit steep price wise. Seems the use of carbon fiber along with the exclusivity of the product allows current manufacturers to charge whatever they please. No mistake both the gruppe m and revolution intakes are beautiful works of art and im sure finely crafted but I am certain I can obtain 90+% of their performance benefit with my own design, still get a good visual apearance, and for far less money.

I am away from my car for a bit and am wanting to know the inside diameter of the section of intake pipe where the MAF sensor sits.

If anyone has a revolution intake or a gruppe m, the inside size of the billet adapter piece would work as well.

This is critical as it dictates air velocity at this point and the ecu map bases fueling on MAF and o2 readings, and the MAF readings will only be valid at a stock size MAF housing.

Doesnt mean there isnt room for more flow though!, that flow will just be at a higher velocity. I know the throttle body is 90 mm ....is the MAF the same?

Thanks in advance for any help on the matter, promise to post pictures and keep updated on any new developement.

[07misanored]

I'll take the fact that nobody responded as not many people know the answer ha. I tore into the stock airbox last night...results: straight section of plastic pipe measures ~3.730" ...about .010" shy of 95mm so we will call it 95mm for anyone searching for this answer at a later date.

In other news I studied the area the stock airbox sits in, and as an engineer I can say I am extremely impressed with the utilization of space...and using 3 seperate inlets to bring in enough air to make it flow decent is impressive as well. The only major problem I see with the stock airbox (which is a big one) is that where it sits. The whole bottom half of the box is nuzzled up right against a cylinder head and directly over a large opening in which the exhaust header is right there less than 6 inches below. So while the stock box might not be bad in CFM flow capability (volumetric flow), the other goal of an intake is to achieve air density (Mass flow: volumetric flow + ) which is where the stock box fails in my opinion. (plus i like intake noise and there isnt much!)

I think I have a design that will lower IAT's significantly to very near ambient temperature helping avoid power loss due to heat soak, and at the same time out flow the stock box by a good margin. Im thinking at least the level of flow achieved by gruppe-m and revolutions kit, possibly more due to a one piece design with more gentle bends, no adapters/silicone, and a higher ram pressure. With the same great sound.... much lower IAT's...more power...I think that would be a winner. Anyone think its do-able?