Well as above really, done abit of a mathematics today using equation e='pie' x R'square' and worked out my exhaust is actually a 2.97"

Is it mean a lot smaller from the inner bore? When someone refers to 3" which measurement do they normally refers to?

 

Think you answered your own question there mate.....no it's a 2.97"

I would keep telling everyone you have a 3"........size matters and all that

 

are you really bothered about thirty thou?

 

Wait, did you measure the inside or the outer?

They generally mean the inner.

 

Well I could only measure the pipework as its already on the car.!! Instead of the inner bore.. so what exactly is it then?

 

Have seen a bit of a difference between various exhaust systems claiming to be the same ie 3" so i reckon they use the best guess method, that or round up to the nearest hole number

 

Hmm... its actually a hks dagger.. got a question tho when ppl refer to 3" do they normally refers to inner bore size? So the pipework would need to beg a lot more than 75mm to achieve that then...?? Right?

 

It should refer to the inside diameter.