[Guest]

My exhaust guy just hooked up my single in/dual out Magnaflow. I originally requested the dual out pipes be 2 1/2", but he convinced me I would have better luck bending around the spare and factory trailer hitch with 2 1/4". He claims the difference in flow would not be significant. Did I make a mistake by going with the 2 1/4"? It sounds great, and I do notice a "seat of the pants" difference in performance. Also he recommended I put some header tape on the dual out pipes to prevent any problems with tire rot or brake and fuel line damage. Any suggestions as to whether or not this will affect performance or is needed? I have zip tied everything that is close to prevent rubbing against the pipes.

 

[nightmare]

i wouldn't recommend header wrap on the back side of the exhaust, or any other part for that matter. only because it traps and holds moisture from rain/sleet/snow next to the pipe, causing premature rusting. if the exhaust shop used galvenized or stainless pipes, you should be fine. there is no hp gain from this. if you used header wrap on the headers, it would cut down on the engine compartment temperature. and, as you know, a cooler engine runs better. anyhow, zip tieing (sp?) the stuff away from the exhaust is good.

if you are worried about heat from the exhaust hurting the brake/fuel lines, you should probably get some 1/8" thick steel, and create a heat shield for the areas in question.

as far as the gain or loss about using a 2 1/4" pipe instead of a 2 1/2" pipe, he's right. if you were to have changed out the pipes before the muffler, ie: from the exhaust manifolds back to the muffler, it would make a difference, i think. less back pressure there, really opening up the system allowing it to breathe better. but again, you're allowing it to breathe better by going from the single inlet/single outlet to a single inlet/dual outlet muffler.

i hope this helps, and if there are any impurities in my "way of thinking," maybe someone can clarify them. thanks