exhaust question

robyn402 · Jul 13, 2009, 08:33 PM

due to some info on other threads i was wondering something before i go and have my exhaust changed slightly

so here goes

-rrm header/dp

-2.5" highflow cat and custom exhaust with a 2.5" twister race muffler
(http://www.flopro.com/Twister.htm) i relise this might just be a muffler but the sons a *****es at the exhaust shop called it a resonator

-aeroturbine 2540i muffler
(http://www.aeroexhaust.com/import_exhaust_2540i.html)

questions are

1) as apparently the 2.5" exhaust is said to lose low end power, would the twister resonator create the back pressure to help gain the low end back? or slow the cardown

and

2) i've got a slight rasp/rattle in the 2500-4000 rpm range, its not loud like a honda its more of a secondary sound mixed in with the rumbley (for lake of a better word) exhaust note that the aeroturbine muffler creates. would a secondary resonator(http://www.aeroexhaust.com/import_resonator_ar25.html) get rid of that slight raspy/rattle?

and incase your wondering yes i'm pretty picky on what sound my car makes

quick vid, i'll try to get a video of a drive by since that the only way you can here the noise
http://s161.photobucket.com/albums/t...t=P7020281.flv

RUBBERDUCKEY · Jul 13, 2009, 09:01 PM

For the rasp and rattle I found that the RRM headers is the reason for this because I put my car (AEM SRI, Magnaflow Axle) side by side to another Ralliart with (RRM headers, DP, & magnaflow exhaust) I found that the other car had more of a rasp and rattle sound then mine. For exhaust I think our piping is sitting at 2.25 which is optimal I don't think 2.5 will hurt much maby during low end power and you may have some issues with gas flows but as long you dont go to 3.0

soulesswarrior · Jul 14, 2009, 01:27 AM

Rock from rrm seems to say 2.5 is big mistake an ill trust rock, he knows his stuff! My car has the raspy kinda sound too from round 3000-5000. I have a rrm header/downpipe with a cat welded in not sure what kind of cat, got the setup from a guy who bought the wrong thing from another ralliart owner. My question though is since the shop press bent my 2.5 exhoust wher the bends are could I just replace the straight pipe and leave the bends since their diamater was effected? My set up by the way is rrm header/downpipe with cat then 2.5 inch to my magnaflow. I don't have a resonator anymore.

robyn402 · Jul 14, 2009, 11:04 AM

Quote:

Originally Posted by soulesswarrior

ince the shop press bent my 2.5 exhoust wher the bends are could I just replace the straight pipe and leave the bends since their diamater was effected?

thats pretty much what i'm looking at doing if i have to

so far the 2.5 hasn't effected much for gas, i get about 600kilometers on the highway

but very curious about this twister thing, if its helps or hinders...has anyone had one of has a friend who had one?

soulesswarrior · Jul 14, 2009, 11:21 AM

From the pix it looks like a resonator to me. Though I've hear diff places call resonators mufflers as well. It all depends what kind of sound you want as I don't think is hindering much. Befor I had my headers when I just had the exaut with no resonator an magnaflow it sounded really deeeep an loud in a good way. Now that I have the headers there's small raspyness but it seems only noticable in cabin. Can't hear it outside its odd

robyn402 · Jul 14, 2009, 02:40 PM

yea this thing sounds good cept for that slight noise for a few 1000 rpm

soulesswarrior · Jul 14, 2009, 02:56 PM

Well I just went back to shop. Guy choped the pipe to the first bend replaced it with 2.25. He said with all the bends it ristricts it from 2.50 to 2.25 so it will be find for now. Cost me 25 bux lol. I noticed some of the raspyness quieted down so dunno why but works for me. Still as loud as it was but less raspy. After I throw my body kit on I'm goin to replace the rest of the pipe and put a new muffler on. He also told me the cat on it is a magnaflow aftermarket so I'm assuming it was the one rrm had.

robyn402 · Jul 21, 2009, 05:26 PM

i'm gunna be knockin my section from the cat to the axle down to 2.25" pipe and i'm thinkin about tossing in two aeroturbine resonators, simply at mid rpms i get a rasp i just can't handle... and hopefully get more growl from this combo

http://www.aeroexhaust.com/performan...ator_ar20.html
ar20: 2 inch inlet and outlet, 4" wide, 4" high, 14" length

OttRalliart05 · Jul 21, 2009, 09:40 PM

I will get a vid this week of my buddies car.....we have proven a header is a WASTE and our dyno results prove it....the power gain is in the DP and cat....the muffler is for sound only....if I am wrong then I ask you to prove me wrong with un-bais proof...take a stock Ralliart and do a catback ONLY and I would be shocked if there was more than 7whp......