my new exhaust

[88'er]

well i just got my new exhaust installed the other day. i had my pipes replaced with 2.5" and a "new cat" installed. its a hollowed out cat with a mated up 2.5" pipe through it. and a Dynomax super turbo muffler with a corvette square tip on it. It looks pretty damn cool! i'll have pics soon! i LOVE the sound except for one thing. in 3rd gear around 3000 rpms i get this metallic rattle kinda sound. my exhaust guy put it back up on the lift and nothing was loose or rattling, and he said he thinks it might be the harmonics from the square tip. i was wondering if anyone else had this problem or knows what this could be?

[zero.counter]

What about the heat shield?

[88'er]

umm, i don't think so because it wasn't there before. and plus we modified that to fit my new header

[zero.counter]

umm, i don't think so because it wasn't there before. and plus we modified that to fit my new header
I am talking about the heat sheild over the exhaust. Mine used to rattle and cause that sound with my raptor turbo muffler, so I removed it and the problem was resolved. The problem may actually lie in the composition of the exhaust itself. If the metal is not high grade or very thick, it will resonate all the way down to the muffler in some cases...

[88'er]

yea, that is what i was talking about, i just wasn't sure if i removed that heat sheild over the headers completely if it'd melt the spark plug wires

[smufguy]

the metallic rattling or the sound of the metal kinda ticking is usually from the CAT. when a new cat is put in place, it usually does that cause its like being "broken in". Not a technical term for it, but u get the idea. Mine did that cause the heat shield on the cat kinda gets expanded and cooled. Give it about a week or two and see if anything like that kinda sound still persists.

[88'er]

ok, but my cat is hollowed out and has a pipe running through it, so its not actually a real cat

[smufguy]

ok, but my cat is hollowed out and has a pipe running through it, so its not actually a real cat

oh, then i dont know. but give it about a week or so like i mentioned and see if it still there. Let the exhaust shop know of this and that u will bring it back in a week or so if the problem still persists. My exhaust did the same thing for about 5 days to 6 days when i had mine put in. I think its just the steel kinda getting used to the heat or what not, but also, i had and have a legal cat, so it was a major component too.

[grove]

mine makes a weird noise to. but i know why i gutted a my cat and its just making an eho noise to it kinda of sounds like a metallic noise. i dont know of any muffler shops in virginia beach area that will hack off my cat and weld a straight pipe. quick question though, does an apexi n1 stly muffler sound descent on our cars. im looking for a deep tone. but not quiet. right know have a header hollow cat and 2 1/4 (i think dont remeber drinking right now) pipe after cat and a dynomax muffler and a 2 1?2 inch tip i think. :beer:

[smufguy]

mine makes a weird noise to. but i know why i gutted a my cat and its just making an eho noise to it kinda of sounds like a metallic noise. i dont know of any muffler shops in virginia beach area that will hack off my cat and weld a straight pipe. quick question though, does an apexi n1 stly muffler sound descent on our cars. im looking for a deep tone. but not quiet. right know have a header hollow cat and 2 1/4 (i think dont remeber drinking right now) pipe after cat and a dynomax muffler and a 2 1?2 inch tip i think. :beer:


unless u have a silencer in the N1 muffler, at Wide Open Throttle, it sounds like ass. friend at work has it on his celica and he failed for loud exhaust. It was just an axle back with just the muffler and no silencer. It sucks IMO. get a dynomax and it looks much better and a sleeper muffler. but yeah if u have sound inspection like we do in NJ, get a resonator. ulll defenitely pass like i did, and its much quieter at WOT and at low speeds, its deep, but not too deep to set all the car alarms off.

[HostileJava]

It's very possible that it's not the exhaust at all that's making that sound but it is causing it. As the exhaust changes notes the soundwaves are changing and as they change they will cause different things in the car to vibrant in tune with them. My moonroof will vibrate like a mofo when my engine hits 2600rpms.

[speedpenguin]

maybe the hollow pipe you welded on to make it look like a cat is vibrating?
btw i'm looking for a muffler, too. one that is nice and mellow, but not loud.
if you have any suggestions?

[88'er]

i dunno what is causing it, but its gotta go! i have a dyno max super turbo, and its pretty loud, but i kinda like it, it is also VERY deep at low rpms, which is hella cool! i dunno what to suggest really, but i'm satisfied with mine other than that damn sound. if anyone knows how to narrow it down for sure i'm all ears!

[grove]

right now i have the dynomax muffler its nice sounds descent. it will set off car alarms all the time. but i would like to find something that is deep and loud all the time and set off car alarms all the time. kind of like my firebird does. :rockon:

[modu03]

unless u have a silencer in the N1 muffler, at Wide Open Throttle, it sounds like ass. friend at work has it on his celica and he failed for loud exhaust. It was just an axle back with just the muffler and no silencer. It sucks IMO. get a dynomax and it looks much better and a sleeper muffler. but yeah if u have sound inspection like we do in NJ, get a resonator. ulll defenitely pass like i did, and its much quieter at WOT and at low speeds, its deep, but not too deep to set all the car alarms off.


hey, where might i find a resonator to put in my car?... i am looking for universal , but all i can seem to find is the short little cat conv replacement.

[smufguy]

hey, where might i find a resonator to put in my car?... i am looking for universal , but all i can seem to find is the short little cat conv replacement.

all muffler shops have em in stock. Thay are like $80. make sure when they weld the resonator to your piping, its tucked up good, dont let it hang like mine cause u will be scraping.

[NXRacer]

ok, but my cat is hollowed out and has a pipe running through it, so its not actually a real cat
i bet thats your problem right there. It might not have been welded very solid or there's something inside the hollow cat thats vibrating on the pipe going thru.

[AccordAddict]

I know my exhaust sort of rattles when i take off but i have a fireball style muffler with 2 1/4" piping its loud as hell always sets off car alarms. I think im gonna get a nice borla muffler when i have the money.