sstockton said:A/R is a ratio, so it can vary from turbo to turbo. A= Area of exhaust inlet and R= Radius of the housing from the center of the turbine wheel to the center of the exhaust inlet. The Area divided by the Radius is your A/R. So really you need to know your A/R and either the inlet area or the Radius, you can't figure it out with 2 variables remaining, there are too many possibilities.
What turbos did you have in mind? If you know the inlet type, like T3 for example, that will give you a decent idea of what you're dealing with since most t3's will have roughly the same inlet area.
:thanks: i appreciate the help. :Thumbup:sstockton said:Yeah the smaller A/R will work better for you. The bigger A/R will allow you to flow more exhaust, but if you're looking for quick spool up and building boost go with the smaller housing.