I ordered an exhaust, which I thought was 2.5", in fact, it was advertised as 2.5", but it turns out it's only 60mm. It's a dual exhaust with an x-pipe.

The problem is I ordered a pipe that connects from the header, refered to hereinafter as "downpipe", to the test-pipe which is 2.5". So we have a 2.5" downpipe and testpipe which leads to a 2.36" or 60mm exhaust and this what happens when they line up.


No Flash


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As you can see a bottleneck has developed. I don't believe this will bode well. It will, in my opinion, negate any of the increased flow made by the down-pipe and test-pipe as it will just bottle neck once it reaches the cat back exhaust. Moreover I think it'll cause turbulence in the exhaust creating a rasp when the throttle is blipped.

Am I wrong, I am by no means an exhaust expert, but I was really angry when my exhaust only measured out to 60mm. What do you guys think, will I be alright? Will the downpipe still increase power despite the bottle neck? If I had 2.5" would I see improved power?

 

Looks like a mismatch to me, have you communicated with the manufacturer yet?

Need better pics too, if possible.

 

The mismatch is because I lined up the test pipe with the x-pipe of the exahust, so you see the disparity in diameter between the 2.5" testpipe and the 60mm exhaust. The 2.5" test pipe is on top, and behind it is the x-pipe so you see how the x-pipe comes in a bit.