so the more i think about this the more since that it makes but i would like someone to correct me if i am wrong, Ok you can buy several different t-stats either 180,160,180 drilled, or 160 drilled and they only cost about 10 bucks each, but i relized if you are really trying to get some good flow why not just take out the t-stat(during the summer only) you would have to reinstall it for the winter so that you could get heat in your car, but then you are saving 10 dollars + the shipping which is about 15 dollars for me, and you would be getting the best flow that is possible