I have a 09 hxdf with a cat converter ( as you know) the pipe has been wrapped etc it still gets way to hot. im interested in an exhaust that will not bust my ears. that may do away with the heater problem also hint hint. also the eng has bad spark knock under a load at 3/4 or better throttle will a tuner help that if so please give me some feed back on an economical way to fix this> prefer blacked out 2 into one exhaust poss.

 

Not sure if you'll ever get away from an exhaust thats too hot. Heat shields always work better than heat wrap.

As for the 'knock'... are you using the highest octaine gas available?

 

You shouldn't have a knock or ping on a stock motor (is it stock?). Like the last reply, be sure to use at least 91 octane gas, try a different brand or station. Another possibility is that you are lugging the motor. That's both harmful and not fun. Might also be your timing is too advanced but that seems unlikely.

 

Put an new exhaust or stock 08 head pipe (no cat). Get a power commander and plug off the o2 sensors. I have a take off head pipe with no converter that I'm getting ready to mod. I heard that Rush exhaust sound lousy with the new catalyst installed...If you don't get inspections go nuts.