Yes on a stock NA KA 3in is way too big 2.5 at the most. I would only recomm 3in for turbo application like the sr20det. When I get around to ordering my sr's exhaust, if i can't find a decent used one, i'll probably be going with a BRM 3in. If I were still runnin the KA i'd actually just keep my stock and *coughgutthecatcough* since I think anything else is a waste of $$ and the stock exhaust is very quiet and very smooth.