Thanks all for the replies. I think I have got used to the sound now, and as cobain913 said, loud music definitely helps. Every so often, I'll have someone sit in my X for the first time (since my upgrades) and comment on how loud it is now. One friend of mine even thought I had a bad muffler

But I'm really happy with the power improvements. I think the FIPK made a big difference, even on my automatic. I was looking at the throttle body spacer, but if it will only make it louder, I'm going to stay away from it.

I guess the next thing to do to boost power is maybe replace the plugs and wires. Any suggestions? From what I've read on the board, the sixth plug can be real tricky. I'm thinking I'll have that done at a shop and do the other five myself.