dat240zg Posted July 30, 2012 Share Posted July 30, 2012 Looking for suggestions here. Current exhaust system is (from motor back): Sanderson headers, stainless 2.5" mandrel bend pipe to a y-pipe joining behind tranny, moving to stainless 3" pipe to a summit bullet style silencer and out to a magnaflow muffler. Motor a healthy LT-1 and the Z is fully dynomatted. From the outside, it sounds really nice - deep and smooth. From the inside, well, it makes your ears bleed. Not really, but close. I seriously have to wear ear plugs. Forget listening to music or talking. I'd like peoples opinions on different muffler options that will lower the noise level to I-can-drive-it-without-resorting-to-sign-language-levels. Thoughts? Quote Link to comment Share on other sites More sharing options...
RebekahsZ Posted July 30, 2012 Share Posted July 30, 2012 (edited) Straight pipe. My car wakes the neighbors, but it is pretty quiet inside. I have a really cheap stereo and I can hear it fine, talk on the cell phone, etc. How long is the pipe that goes from your muffler to the atmosphere? I have seen lots of guy running a really short pipe there and that may let noise out too close to the underside of the rear valance, pumping all that noise out under the car. Whatcha think? Edited July 30, 2012 by RebekahsZ Quote Link to comment Share on other sites More sharing options...
rejracer Posted July 30, 2012 Share Posted July 30, 2012 I have a mostly stock 94 impala, and I am running dual flowmaster delta 70s. I like the sound, it's very mellow yet still makes some noise when your on it. I think it's close to the perfect street muffler. The system is a dual 2.25" with an H pipe and stock cats. Quote Link to comment Share on other sites More sharing options...
bjhines Posted July 30, 2012 Share Posted July 30, 2012 There are a lot of things that can help. The interior drone can also be induced by engine, tranny, and exhaust components touching, or mounted too firmly to the chassis. There is nothing a muffler can do to help that kind of drone. Your floor-pan makes a great speaker with engine vibrations acting as the voice coil. adding a balance tube near the collector can help. Using a larger internal volume muffler can help. a smaller pipe size after the muffler can also help with minimal effect on exhaust performance. Zs have rear mounted mufflers so there is no exit pipe length to speak of. installing a helmholtz branch resonator near the entrance to the muffler using 2 different mufflers in the system can also help reduce a wider range of sounds, each muffler handling different fundamental notes. The initial muffler is really just a resonator because it does not reduce high frequency sounds at all. The resonator needs to be a relatively large internal volume to do it's job, most of these bullet resonators serve no purpose in conjunction with a primary muffler of much larger internal volume. Quote Link to comment Share on other sites More sharing options...
letitsnow Posted August 2, 2012 Share Posted August 2, 2012 Which magnaflow? I have a pair or their oval case(looks like a regular muffler) on my 5.3L rx7, it's a very nice combination of sound but not too loud. If you have the round case muffler, you might consider switching to an oval. Quote Link to comment Share on other sites More sharing options...
rags Posted August 3, 2012 Share Posted August 3, 2012 I used a Magnaflow 12198 instead of a Y pipe. From there I have 3" mandrel bent stainless to a flange just before a Magnaflow 11229 in the stock mufler location. I also have a straight pipe that is the same length as the 11229 with the same tip on it. I can swap out the straight pipe for the second muffler for those times when I'm feeling "old". Best of both worlds! Joe Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.