MAF Coupler Size

[InfiniteGSX]

My coupler went missing and I've been using it for years.

Everyone says:

4 inches to 3 inches coupler is what you need

1g mas - 3 1/8 inches (3.125)
2g mas - 4 inches (4.0)
3g mas - 3 1/8 inches (3.125)

and it is fine to use a standard non reinforced, that side of the turbo does not see charged air.

But It is smaller than 4". I have plenty of 4" Couplers including some from FP and they are too large. They fit the turbo just fine, and the turbo side of my FP Intake just fine but the MAF Side they flap around and when I try to clamp them down they try to fold over on each other.

What is the correct size?

 

[whe3ls]

2g is 3.75. i tried a 4inch coupler way to big

 

[InfiniteGSX]

Cool thank you. I was guessing 3.75 but didn't wanna get it and it was the wrong size also. I even think the last coupler I had I never bought, just came with the intake .

Thanks A Lot!