I am in search of an exhaust leak on my Long Tube header flowmaster cat back. I cant see any visible burn exhaust marks anywhere, and I dont feel anything with my hands around areas I can reach. Ihave repalced all clamps, gaskets more than once and no change in tune, as it acts like there is a leak.
Personally I think its the way the engine runs at idle with the cam and GM crappy designed LT1 manifold.
Can you put a stethescope on and hear a leak?
Just looking for an economical way to see a leak? Maybe SEAFOAM?
Thanks

 

cover the muffler outlet with a rag, then use a stethascope - you will very easily be able to tell where it is coming from then