(This one time, at band clamp....) Sorry, couldn't resist.
Are they stepped band clamps? I had great success using stainless stepped band clamps when I got my CME tips chromed on the 4th gen. Fits the pipes better with no leaks. Got them from a place that sold school bus parts of all things. MUCH cheaper than using the "brand name" clamps and accomplised the same thing.
Another "tip" as it were, if the ends of the outer pipe aren't split-tailed, you can cut a short slot on each side (without going past the inner pipe depth and band clamp coverage area causing a hole) to help allow the pipe to be clamped down further.
Just an idea.
And Rodimus, that's not you, that's Ahhnold. Here's the one of you:
2010 2SS/RS Auto, Sunroof, Engine Cover. Transformer Edition package.
2013 ZL1 ragtop #5478. 1 of 54 CRT M6 'verts.