Vacuum Tuning

Well it would seem that this subject has many threads on various forums. The results all seem to point to a faily low level of actual data to provide any real help. I did run across this. http://mewagner.com Some good information and of course they want to sell their product. But some logic as well. The wrong PCV valve could cause issues with idle and also offer long term problems. They even offer money back guarantee for 30 day trial. Even gave me an idea. I will take my F valve and drill a hole to install a vacuum bung and use their test to see if the valve opens at idle. I suspect it does.