Same size hosing as pipe?

[ClassicalBor]

for my intercooler piping i am getting, which is 2.25in. do I want to also get 2.25in silicone or step up to 2.5in so it fits easier and then just strap it down tight??

 

[staticbrainwash]

Proper english please.

As for your question, silicone is set up so that it fits whatever pipe it's sized for. So a 2.5" silicone coupler, will fit a 2.5" od pipe. Or in your case a 2.25 coupler will fit a 2.25" od pipe.

 

[oldman420]

You could strap down that 2.5 coupler tight and it would work, but you would more likely run into boost leaks down the road. Your main concern thought should be turbulance. Try and picture air flowing from a small pipe into a larger pipe and back down to a smaller pipe. This action would cause a resistance caused by drop in pressure and then back into you increase of pressure. It just wouldn't flow right. therefor 2.5 " piping = 2.5" silicone couplers.