sorry about the question but i kind of searched and i didn't really find nothing for me but i have a civic with a mini me y7/p08 head and i have 225 compression on all cylinders. my question is would it be ok to put a 2.5 piping for my eshaust or is a 2 1/4 better for my 98 coupe.

 

go cheap, its not gonna help you out any with power. maybe 1 to 5 hp max. not gonna be noticeable. you can gain that by cleaning or replacing your airfilter, sometimes more.

get whatever exaust system appeals to you the most. ie looks, materials, price and sound. just look on youtube and there is tons of pages of exhausts

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