I honestly think that having holes or leaks in your exhaust does effect your performance and aconomy.My ea had a shagd oridgenal exhaust on it and it had a hole in the rear tail muffler it was under power and was geting shit aconomy.Now i have my new system on it and it goes alot beter smoother and my aconomy is a bit beter.and thats on a engine with low compression in cyl 5
