I ran open filter and I could barely hear it. I switched back because of the awful intake temps. I was sitting in line at San Antonio Raceway to get some solid quarter mile times and it would climb over 110 degrees every time in 50 degree weather.
I was running summer quarter mile times. I'm also thinking the track had something to do with it. Took a single data log and saw some funky stuff from one of the runs compared to the regular logs I have.
You should be able to get some good info, it'll just take longer to build up larger stats.