Hi, does anyone know what is the diameter of the primaries on a DC JDM 4-1 Header with the 2.5" collector?

 

"The DC JDM has a 2.50" OD x 2.37" ID collector. The JDM ITR has a 65mm (2.56" OD) x 55mm (2.16") ID collector. The ID on the ITR JDM is smaller due to the anti reversion chamber in the collector and is actually a little smaller a couple inches in from the end of the collector. The JDM ITR has 43mm (1.69") OD primaries (I don't know what the wall thickness is) and the DC JDM has 1.75" OD x 1.62" ID primaries however the DC JDM primaries are a little longer than the JDM ITRs."

https://honda-tech.com/forums/acura-...-2-5%22-77057/


B18