Choosing the Correct Intercooler/Charge Pipe Size
I have been thinking of this topic for quite some time now and after running a few searches, I feel like this would be good to discuss. There must be a precise and correct pipe size for your specific application, correct? Depending on the number of cylinders, the size of your intake ports, and size turbo you are running, etc... you should have a specific sized pipe for maximum flow.
Having too large of piping can yield boost lag. Your turbo is trying to fill the pipe instead of feeding the cylinders. The longer it takes to fill the piping, the longer it will take to achieve peek boost in the cylinder. On the other hand, have too small of piping can have a negative effect too. Although you decrease boost lag by being able to pressurize your entire system faster, you loose high flow capabilities.
There must be a mathematical equation that can give you a specific sized piping. Thus giving you maximum flow. I would like to hear some ideas from others on this as I have a few thoughts in my head about how to calculate something like this.
Last question, from where are you getting your PSI readings from? Are you measuring from the intake plenum, or from an individual runner. I ask this because it makes sense to me that the closer to the cylinder you are, the more accurate of a reading you are going to get.