Any problems putting 3’ exhaust on 70 Dart ?

To answer your question yes you can run three inch all the way back on the 70 Dodge Dart it will be tight and questionable if it would be worth the effort. But that being said if 3 in what you want then by all means go for it. there is a difference in sound between two and a half and three inch exhaust no doubt. I ran twin 3-in exhaust on my 340 straight back with turn Downs right behind the differential no x pipe no h pipe just pure separation from the banks I can't count how many people have commented on how badass my car sounds and you know... I agree.