I just put one one with the stock MAF. No dyno results, but I can tell you how it drives. I noticed a marginal differece, but it was about what I expected. A little better throttle response, car doesn't feel quite as sluggish. It feels a little stronger, but not anyhting amazing. I see you already have a K&N filter, so you may notice less of a difference. I went from the stock air filter with ~8500 miles, so that was probably a good part of the difference itself. I'd say 8 hp may be a bit hopeful, but I can't say for sure. On a side note, it was a pain to install, but not as bad as some others have posted. I didn't need to cut anything off the pipe, and I have a strut tower brace which made things harder. Without the strut tower brace it would have been much easier.