So i have been working on my basket case 1975 CL 360. I have finished work on the engine. Next is frame, then carbs. I bought a complete set of vapor blasted factory carbs for the bike. I have the rebuild kits from Common Motor to replace the parts to ensure the carbs are right. New floats will be installed. My headers are in good shape, but the previous idiot (I meant owner) literally used crimped galvonized plumbing pipes for the muffler/exhaust. I purchased Emgo exhaust mufflers (similar to their shorty but 15 inches in length). I will be using new stock air filters from Common Motor. Will i need to rejet or will the new mufflers be close enough to stock rgarding back pressure?