I purchased the Header, Free Flow Cat and muffler from Rockreeper to put on my 85 Toy. It originally came from Downey. It is a 2 1/2" flow. I was calling around to muffler shops about getting it installed and the shops are recommending 2 1/4". They are saying that I would lose top end horse power. I am going to have to replace all of the exhaust pipe. The engine is basically a stock 22RE. Should I go with 2 1/2" or should I choke it down to 2 1/4"?