are you running any "meows"?

1 hi flow cat + 1 resonator. Thinking of adding another resonator but I'm not sure if it'll affect air flow.

i have a hks hi power turbo back system with a genie high flow cat. its fairly quiet compare to many other wrx i've seen on the streets.

was just about to ask this.

will it?

I understand, I've heard many an X-force exhaust in my day, be it S/S or Ti. Trust me, the difference the diameter of the muffler tip makes is huge. At one stage I had a Tanabe Racing Medallion exhaust - setting off 4 car alarms is just warm-up when I go to any multi storey car park. Me and a friend in an S15 (A'PEXi N1 exhaust) had a wager who could set off more alarms in the Curtin multi-storey car park - I won with a total of 16 alarms on all 3 levels. No excessive revving, just normal driving.

The Tanabe exhaust was a 3.2" straight-through design, no resonators, no cat, barrel muffler with 4" tip. I subsequently sold it for an MMS 3" exhaust with 1 resonator, oval muffler with 3" tip. You wouldn't believe how much quieter the MMS exhaust was by comparison. My next rex came with a BPM 3" exhaust with 1 resonator, barrel muffler with 4" tip, it was much louder than the MMS one.

From memory, the X-force exhaust came with a 4.5" muffler tip. Trust me, with the same exhaust, just going to a smaller muffler tip will result in a drastic drop in exhaust noise/drone. Just think about it for a second, a silencer works in the same way - essentially just reducing the diameter of the muffler tip.

In my opinion, a 3" muffler tip is perfect in terms of still retaining the boxer rumble and some noise without being overly excessive. A quality exhaust system that falls into this category is the MMS and RMS exhaust system. Then again, some prefer it as loud as it goes, so it's all about preference.

At the end of the day, if it's too noisy/droney, my suggestion is that a smaller muffler tip will help a lot. And it's the least costly of all the options, as compared to a new muffler/resonator/cat/exhaust.