2cokeman

I saw dyno sheets that showed a 4 rwhp gain and 2 rwtq gain, you can find the article in a google search

ckone0814

had one in my GT at the start but have since went cai/tune (WOW!). never noticed anything with filter, performance or gas mileage wise.

still have em on both my DDs and find the oiling to be a real pain in the a$$. now that i read goldenpony's post i may switch to the no-oil Amsoil.

i know it's not really an answer to your question but i say save the $50 and put it towards cai and tunes. there's no easy or cheap way .