Break in period for new headers?
 

Hey guys! I recently bought a new header (Tomei UEL Header) for the 86. My follow up question is: Is there a "break in" period for the new header? Obviously it'll sound awesome and rumbly but should I drive it slowly to "build" up the carbon in the header? Reason I ask is from doing some prior research when I got my cat back, members would say to let "carbon" build up.

no. but make sure you check the bolts after you heat cycle it a few times.

Da fuck? First time i've heard of that with a header...

In general i think the muffler "break in" is a buncha bullshit. There is some merit when it comes to mufflers with packing material, as time goes on it does deteriorate would change the sound, however I never experienced it even after a few years.

When it coems to chambered mufflers like flowmasters etc, some say carbon build up changes the tone, I call BS on that having had a flowmaster on my old car for nearly 20-30kmi and it never sounded different to me.

@Shady195 You can call BS if it makes you happy, but there was a definite change in my setup which included a cat, resonator, and a canister style muffler.

I doubt there would be a change if there is no cat, resonator, or muffler.

every exhaust I have ever had on bikes, cars, and trucks all changed sound after the first 500 or so miles.

It should quiet down a bit once it 'breaks' in. Just enjoy and maybe check the bolts after some heat cycles if you experience any exhaust leak symptoms.

My EVO 3 really changed after carbon build up

Mufflers change sound as they age, but there's no real "break in" process for exhaust components. Bolt it on and go.