No it won't hurt anything. I have a test pipe, catback, intake, and about to slap a header on with no tune. I will be getting tuned soon, but you will be fine.

 

i put it on feels and sounds great!

 

to get the full gains out of the test pipe you should get a tune. but even without a tune you will still get some gains

also 350 to tune a neo seem very expensive?

 

can't wait to put my test pipe on. got the intake and exhaust. is a header worth it after the test pipe? I've heard people say the stock header is pretty good already...??

 

^thread jacker!!
JK
umm thats really up to you the stock header is a great design, and most headers that are any good are very expensive.

A test pipe is worth the money to anyone and everyone because its cheap power. A header on the other hand tends to be expensive power..

 

yeah i got a custom fabbed test pipe and cat back on my car, i feel the mid range improvment. i bought a header on ebay for 1dollar, but the shipping was 45 lol. 46 bucks is a great buy. now the material T 304ss and it was cnc bent all the same things that the 1000$ ones were showing. I figure they copied a berk or toda etc. specs and as long as the buid quality was good i assumed it was good., I am scared to put it on because i dont wanna lose power , but shouldnt it at least be better than the stock and at least the same but not lose power?