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Im going to do a cat delete on my summit and have a few lenghts of pipe to have welded in and need to find the nearest diameter to where the pipe enters the cat. I think the cat removal will allow the engine to breath a little better. With 160k on the cat, im sure its a liitle plugged up.

Thanks,

http://info.rockauto.com/Walker/Detail. ... -10754.jpg

Appears the exhaust clamps are 1-3/4", so that should be the outer diameter of the tubing in the system. Sounds familiar when I worked my 1.5L exhaust back together.

I did search around, didnt find any one specific answer. Thank you

Mine has stock exhaust, but the pipe before the cat def looks larger, just like in the walker diagram.