Can anyone tell me the JCW exhaust size at all? Are the mufflers on the JCW too restrictive? Thanks in advance

 

I believe the one I removed off my GP was 2 1/8" (something metric) int eh center section, then gets smaller for the individual tubing out of the mufflers. I can have someone check for sure tomorrow at the shop if you like. Just let me know!
Hope that helps!

 

Yes please. I am really just after the size of the pipes going to the mufflers.

 

Ok will see what I can do!

 

Well, the JCW exhaust runs about 3.75 PSI backpressure...the stock runs 2.5 PSI for reference.

Those numbers were taken from a thread on exhausts over on Mini2. I can pull up the thread itself if need be, but I am lazy and tired right now and don't feel like it.

- Matt

- Edit -

De-lazied myself and found it here: http://www.mini2.com/forum/engine-dr...g-results.html

 

Lots of good info here about stock JCW vs. ALTA.
https://www.northamericanmotoring.co....php?p=1835576

It uses 2.25” diameter tubing, and were it splits into 2 mufflers it goes to 1.3” tubing. The ALTA exhaust uses 2.5” plumbing through out with no split. So bigger should make more power?? The weight of the JCW system was 40.8lbs, were as the ALTA system is 28.0 lbs. So our save a bit of weight over the JCW, which you would expect with the single sided system. So onto the dyno test. This test was also done back to back, and the car was left on the dyno between run sets.

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Good info Jeff!

 

So they don't change the Pipe size from JCW to GP? When I had to get a new cat size, the dealership said it was about 2 1/8" Main pipe size, and where it T's it look bigger than what you guys say though. How restrictive are the mufflers on this kit