Here is a MT2, 1/10 stadium truck with a big block Savage 25 engine with a stock big block Savage 25 exhaust with little or no modifications.
http://www.rcuniverse.com/forum/m_5176805/tm.htm

All so this is the stadium truck forum not touring car so why are you talking touring car. I have seen plenty of stadium trucks with big blocks and stock or near stock exhaust and proof is in the above link. [X(]