Diff between FI 12" & 18" resonators
 

Hey guys what's the difference between to 12" and 18" resonators on the fast intentions exhaust system?

12'' resonators are just a tad louder than the 18's, But the overall length of them are the same so you could swap them out if you wanted it a little louder or quieter.

Most people use the 18's for a daily and are pretty happy.

Would you say that 18" is necessary for keeping daily driver tolerable sound levels if you want to install headers+test pipes? Or would 12" also keep volume low enough?

I'm wondering because I'm probably gonna have to trade my Litespeed exhaust if I go down that path. It's already loud enough with stock headers+cats.

It you stay with stock headers and cats go non-res catback. If stock headers but HFC's or test pipes go 12" res, if LTH's or shorty headers and HFC's/test pipes go 18" res.

Litespeed is a system all its own lol. Whatd you expect for noise levels to be with a flat out muffler delete? lol I'm running the litespeed with Z1 test pipes and Momentum headers and this bastard screams lol. I feel bad when passing people sometimes...

:icon17: but not really.

18" might not even cut it to be honest with headers/TPs... Resonators don't necessarily quiet the whole exhaust, it kills "annoying" sounds like drone
At the same time how loud is loud for you, from what I have heard, LiteSpeed drones like a motherfùcker and is loud as all hell when you step on it.
On my car my Stillen exhaust is ok, no complaints. When I added TPs, it was a TOTALLY new exhaust, that thing SCREAMED, I could deafen people when downshifting.
All that beating said, you NEED 18" from what you've stated

I'm kinda new to the Z but owned a G37 before...I currently have the Gredddy spectrum elite exhaust, if I just add HFC will the system be to loud? I'm not interested in waking everyone up....but I love my greddy exhaust none the less :)

actually I was surprised the drone levels weren't higher with the litespeed. It does of course have 3 giant resonators but I've definitely driven with worse drone before. Then again....I think I'm a race car driver.:roflpuke2:

No YouTube clips?
HFCs add a decent amount of extra sound, not like TPs, most noticeable thing is that the add a hissing/whooshing noise on deceleration

:iagree: Resonators will cancel out some drone but not necessary quiet down the exhaust. And yes, everybody has a different definition for "loud". That's why I always suggest people to go out and hear the exhaust for yourself.

HFCs are quieter than test pipes, stock cats are quieter than HFC. It will be pretty loud if you add the HFCs but not too crazy. But then again, like I said above, my definition of loudness could be different than yours. I can only give you MY opinion.

^ I know this guy :icon18: and this exhaust:tup: get ready for hiss.. When changing the Stock cats..

With the LTH my sounds like an exhaust leak or something metallic when letting off the gas in certain rpms.

I'm running 12" resonators on my DD with stock cats and I love the sound. I've never felt the drone was too crazy. The sound outside of the car is virtually indistinguishable between 12" and 18".

6 inches. I think.

:icon18::icon18: