i have a d15 with an ihi rhb5 with a 2.5 open downpipe it ran fast with the open exhaust now i had to hook the full exhaust(2.25 no cat) up again and it is slow it doesnt seem to be right having a small motor small turbo & big exhaust wtf

 

I could have understood you a little better of you used punctuation in that....sentence?

Turbos like to have as little back pressure as possible. That is why they say "The best turbo exhaust is no exhaust".
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ok the difference is night & day. With the open pipe I was even with a b18 hatch which is good for me having a 1.5 What "quiet" options do i have i was thinking of getting 3 inch midpipe

 

that 2.25" exhaust is probably causing a lot of back pressure for you.

I'd go with at least 2.5" downpipe all the way out to the muffler. Get a a straight pipe or a high flow cat.

Or you can keep the current exhaust system and slap an e-cutout on the downpipe for when you wanna open up a can.

My buddy has one on his Turbo'd Si. With one flip of a switch on the center console the exhaust gasses bypass the entire exhaust system and all hell breaks loose.