I got a SS polished DC header 4-1. I'm wondering if this is the JDM or the normal 4-1 SS one that DC used to make?

What is the diameter on this one? I want to get the Comptech Exhaust, will I have any issues with bottlenecking?

I was thinking about the DC or RSR exhaust, but those are both chambered.

 

pics

 

the jdm one has a 2-1/2" collector. if yours does not, then it is the standard DC 4-1 header. if it is not the jdm one then most any exhaust will be fine since most are made for a 2-1/4" collector (standard DC 4-1). if it is the jdm one you'll need to buy the flange to bolt up the exhaust system as well as use 2-1/2" piping on your exhaust system.

 

Maybe a stupid question. The shop replaced my 4-2-1 ceramic w/ the 4-1 SS one. How can find out if the header is JDM?

 

did dc make jdm 4-1 headers in ss? i thought they didnt but who knows