I'm gettin ready to fabricate a cold air induction set up. I've found that both 3" pipe and 3 1/2" pipe fit on the MAF. From a performance stand point what size should I go with to get the best resuts. As soon as I'm done I'll be taking updated pictures, just incase anyone is thinkin about doing the same. Thanks Ya'll

 

The setup I have is using 3.5 inch, no problems... runs as well as the ram air box I used to have there..

 

I don't have a custom one but I would think 3.5 is better -more air