Ever since I swapped my exhaust from the standard exhaust to a big bore my car doesn't seem as quick I've been told it lost back pressure can anyone tell me if that's true

 

If you slapped a larger bore exhaust on a stock (1.6L in U.S.) 1996 Civic then you just wasted your money. Bolt-On parts add zero to little gains for these engines and that has been mentioned in hundreds of threads over the years. Please trust that Honda engineers are smarter than you or I and they know that bigger is not always better (kinda like **** dudes with floppy johnsons.) Here's a related read: https://shop.advanceautoparts.com/p/carquest-wearever-drum-brake-wheel-cylinder-wca37785/3640566-p?c3ch=PLA&c3nid=3640566-P&adtype=pla_with_promotion&gclid=Cj0KCQjw0a7YBRDn ARIsAJgsF3MLHOlmvwkEzWx-hkuKPz1qnHj15m2ggijpXYnmHS-_Pa9g5MJHkcMaAs5dEALw_wcB&gclsrc=aw.ds

 

^ This "related read" seems to me to be unrelated