hey guys
have a JDM ITR swap done; with 2.5'' custom dual exhaust; high flow catco cat; jdm dc sports 4-1 header, aem cai, ngk wires and sparks
exhaust just installed; custom stainless with mangaflow mufflers.
getting slight backfire when i lift my foot off accelerator..
wondering if its the exhaust setup..or...?
how to most efficiently figure this out?

anyone in Cleveland, OH that could help..?

Peace