i just installed some kinetix HFC..just wondering if the tone of the exhaust will change as the cats get broken in...its got a mean sound right now but i dont know if i like how it has gotten a higher pitch...btw i have intake, spacer, headers, and the stock cat back. thanks for all replies in advance! warriors in 4!!!

 

bump

 

from all the coupes that ive heard with HFCs, the exhaust was noticeably deeper, not higher. my own included. let them break in...give 'em a few hundred miles.

 

thanks hero..we can always depend on you for help!...notice any weird vibration noise at higher rpm's?

 

i myself do not experience any vibrations or noise at higher rpm's. do the kinetix HFCs use the stock support or do they just hang there?

 

no stock support..the cats i have are a custom set made by kinetix to have better clearance. ive had their cats before but sold them cause i couldnt stand the rattling/ringing/metalonmetal sound. i talked to them and they told me that it sounded like a clearance issue (even though i removed the heat shields) and sent me a custom set. the noise is a lot more subdued with this set but i still hear it when the car is warming up..and i can hear it off and on when driving at around 3.5k rpm. im going to give the cats about 1 1/2 week to break in and see how things are going then...i might have to wrap them with some header wrap and see what happens..but i must praise kinetix for their customer service..stand up guys that stand behind their product.

 

I noticed that my HFC provided a deeper and louder note. Absolutely worth the money. I love the difference in tone and volume they give you. Fast Intentions FTW!

 

was it deeper and louder right away? or did it sound like that after a couple of days? and what mods do you have? ive basically done every simple bolt on besides pully and exhaust so maybe my note is going to be higher pitched? not sure bout all this but just throwing ideas out there..

 

never mind...just saw your sig. so we have the same bolt ons...just wondering if it sounded deeper right away. dont get me wrong..the exhaust sounds mean as hell..but i cant help but miss the deeper tone of the stock note. just wondering if i can expect my exhaust to deepen up a bit. from what ive read it should..but just wanted to know if anyone has experience with this..thanks!

 

Like most (if not all) mods, especially breather mods – it’s difficult at best to give a blanket explanation… You might not consider my experience viable since I’m sedan… but I have gen 1 Stillen exhaust – which on a sedan is louder than others (from what I’ve heard) others have different opinions… anyway I expected much deeper and slightly louder tone when I installed Crawford cats, but honestly it wasn’t much different at all… I was really surprised!

Performance-wise I definitely felt a difference… I know people hate butt dyno - however I know my car (very well) and I gained trq without a doubt (after tune).

So to ask what to expect sound wise is so incredibly variable… I have heard other HFC on my yr sedan sound much louder… and I suspect quieter exhaust with Crawford would sound louder… When it comes to intake and exhaust it might seem like apples to apples, but in many situation it’s apples to a slab beef (not even oranges) depending on what you are running.

Sorry it’s not the definitive answer you are looking for but what I’ve found on these boards is that so many people are looking for “an” answer… there are just too many variables for one answer… For me that’s the intriguing part – find out what is specific to your car and mods… Amazingly there are WAY different results to the myriad of options we have.

Bottom line = OP, if you state what intake, exhaust, and cats you have in addition to what car you have – you will get a viable response to your question… as is, it could be anything – literally.

Edit: in response to the “vibrations” question – it might be easy to assume it’s a rattle somewhere, but be sure it’s not ping/knock that you are hearing… I am not suggesting you aren’t knowledgeable enough to know the difference – but with HFC it’s not uncommon to run lean and you might hear knock if the A/F is not adjusted…

 

thanks for the response,

intake- popcharger/ztube
spacer-motordyne 5/16
headers- topspeed
cats- kinetix
exhaust- OEM

and how does ping/knock sound? wouldnt my ecu counter the ping if its happening by pulling timing? this sound ONLY occurs at a certain RPM for like a second and kinda diminishes as the car warms.

 

to answer your initial question I believe the Kinetix cats are a bit louder and thinner/tinnier than Crawford (from what I've read) but with OEM exhaust I'm surprised it’s that bothersome... I'm not sure if you are coupe or sedan but I suspect coupe because sedan OEM is pretty tame and quite... you might want to look into free flowing exhaust – it won’t help the sound in fact it will get louder, but it will help your performance and might deepen the tone (depending on which exhaust you get) ... I believe over time the cats will probably mellow and get a deeper tone but someone with your brand would have a better idea...

As for ping, it's a slightly metallic rapping (very rapid)... many times it's not so noticeable so if the "rattle" you hear is ping it's not a slight ping - but the fact that it happens so brief in a specific rpm makes me think that might be it... and yes the ECU will pull timing to overcome it. You run high-octane gas right?... Do you hear the sound when revving while parked? Or only under a load? If you can hear it while parked you should be able to kneel under the car and determine if the sound is coming from the cats...

Sorry for the long post. Hopefully you find the problem...

 

sound only occurs in neutral or park...

 

^whoops...what i meant was sound DOES NOT occur in n/p..and yeah i run high octane gas

 

sorry to steal the thread but how long do HFC last FI