Anyone run high-flow Cats to reduce hydrocarbon exhaust smell?

Timing! Please tell us the curve? Cam specs? My car would burn your eyes outta your head at 15 degree initial. I thought that was aggressive. I was coached and ended up at 26 initial. The car fires up with a flick of the keys. Idles nice and is crisper then a Doritos chip. I have a big cam and will always have overlap rich conditions but is far better then it was