tankbob Posted October 26, 2014 Report Share Posted October 26, 2014 Since Ive owned my car Ive had a apexi fartcannon on there with turbo back 3in exhaust, always hated the look but it sounded great. Recently decided it was time to go quieter so I bought a cherry bomb vortex that someone on here reccomended. It is 3in single inlet and dual 3in outlets, from what Ive read on the muffler it is not supposed to drone but to fit the muffler the shop had to create a near 90 degree bend before the muffler where before it was much less. I know if I go back they wont weld me new pipe that has less degree for free so should I dump the muffler and try something different or does that bend create this ear piercing drone that Im experiencing? Muffler did make the car a little bit quieter behind the car but my issues with noise level is coming from the front of the car, does the balance shaft delete create noise? I have stock motor mounts, possibly a exhaust leak? Doesnt sound like I have a leak though, its just dam loud. Link to comment Share on other sites More sharing options...
tankbob Posted October 28, 2014 Author Report Share Posted October 28, 2014 Anyone? Im going back tomorrow to talk with the guy about it, Im certain now the cherry bomb vortex should not drone. Link to comment Share on other sites More sharing options...
ucw458 Posted October 28, 2014 Report Share Posted October 28, 2014 Post a video of it. I was debating getting the cherry bomb vortex or the flowmaster dbx. The cherry bomb is still a glasspack. If you want less drone and noise you need a resonator farther upstream. I have a 16" resonator where the 2nd cat should be. It really quiets things down. Be careful with exhaust shops. Most only have cheap resonators like this one that chokes down the size of the pipe and restricts flow like this one. https://encrypted-tbn1.gstatic.com/images?q=tbn:ANd9GcQawBJbuCL6CV2aUWdW50GLysUbDp_OHfcp098GB-HvU7gqOC4H You want one that looks like this on the inside. https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcTrnrfGpLo9mOoVKGe6BvMlzO345iy_egHKf_qGqlhkDO2dznMwfw Link to comment Share on other sites More sharing options...
tankbob Posted October 28, 2014 Author Report Share Posted October 28, 2014 Post a video of it. I was debating getting the cherry bomb vortex or the flowmaster dbx.Ill get one tomorrow, that flowmaster one would fit pretty good but the cherry bomb vortex is huge. I cant get a video of the drone though its only at a certain rpm under load. Link to comment Share on other sites More sharing options...
ucw458 Posted October 28, 2014 Report Share Posted October 28, 2014 Trust me dude. a 12-16" resonator doesn't look like it will do much but it really does. Link to comment Share on other sites More sharing options...
tankbob Posted October 28, 2014 Author Report Share Posted October 28, 2014 (edited) Trust me dude. a 12-16" resonator doesn't look like it will do much but it really does.Does the exhaust effect how much noise comes from the front of the car? Because the car sounds fine from the rear at idle. Im still stuck on that its that bend creating the drone because it had zero drone before with a louder muffler. And would having a flexpipe on my car make the engine louder at the front? Car came with it so I dont know how old it is, could it get messed up from unbolting the exhaust and bending it/ make it hold weight of exhaust. Edited October 28, 2014 by tankbob Link to comment Share on other sites More sharing options...
TexasQuest Posted October 29, 2014 Report Share Posted October 29, 2014 I added a flex section to my 3" exhaust and it made no difference in sound. Link to comment Share on other sites More sharing options...
ucw458 Posted October 29, 2014 Report Share Posted October 29, 2014 Different mufflers accentuate different frequencies. On my old ford at one particular point on load/throttle it droned so loud you couldn't hear your passenger if he was screaming. You may just be getting that frequency attenuated by the new muffler. Adding a resonator should help. Link to comment Share on other sites More sharing options...
importwarrior Posted October 29, 2014 Report Share Posted October 29, 2014 exactly put a resonator on it. i went a different route i had a drone sound as well with my muffler.i put a bullet muffler where the cat should go. no more drone. http://www.summitracing.com/parts/wlk-24219/overview/ $50 bucks. still has the deep tone but so nice to drive with. i can actually talk with out yelling.and my ears dont ring anymore once done driving. Link to comment Share on other sites More sharing options...
tankbob Posted October 30, 2014 Author Report Share Posted October 30, 2014 (edited) Im all for a resonator but not sure where Id put it, Im a bit scared here in cali to run around with no "cat" since mine is most likely gutted anyways. With how big 3in exhaust is I already scrape or very close to in the other areas I could put the resonator. Also how do you figure out the right length of resonator to run? Edited October 30, 2014 by tankbob Link to comment Share on other sites More sharing options...
importwarrior Posted October 30, 2014 Report Share Posted October 30, 2014 they come in many different lengths i had one behind my cat just measured the length and searched for one with the same overall length.cost me 30 to have it welded in. Link to comment Share on other sites More sharing options...
jszucs Posted October 30, 2014 Report Share Posted October 30, 2014 You don't look like your that low in your sig pic to be scraping. You might need to take a look at / rework some of the hangers / hang points on your exhaust to tuck better. They could also be causing vibration and drone. With a bit more restrictive muffler you could be just sending the right frequency at that RPM causing drone. I would 100% get that bend out of there if you can. Adding a resonator is a great idea to change the sound. Might try a different muffler designed to sound deaden VS a glass pack style muffler. Link to comment Share on other sites More sharing options...
tankbob Posted October 30, 2014 Author Report Share Posted October 30, 2014 (edited) Went down to the muffler shop this morning and Ive got a few things to report. First off this guy has only been doing exhaust work here for 2 months and had never heard of drone until I told him about it and then took him for a little spin down the block. This doesnt bother me because he is a great welder he previously build race trucks, the shop owner who knows a lot more is on vacation in peru for the next week so Im going to wait until he gets back to get his opinion. If it is the bend that causes the issue they are going to correct it for free. Also turns out my exhaust manifold leaks in multiple spots so I want to correct that before adding a resonator, flexpipe doesnt leak at all. Should I try retightening the bolts on the manifold or just redo the gasket entirely? If Ive got to redo the gasket Ill wait until I can afford a turbo rebuild kit and do those at the same time, is drivjng the car with an exhaust leak harmful? Im very excited that I finally found what makes my car run so lean since this has been an issue for a while now. Video is uploading and will be at this link shortly.https://www.youtube.com/watch?v=QDiH_y2_alA&feature=youtu.be You don't look like your that low in your sig pic to be scraping. You might need to take a look at / rework some of the hangers / hang points on your exhaust to tuck better. They could also be causing vibration and drone. With a bit more restrictive muffler you could be just sending the right frequency at that RPM causing drone. I would 100% get that bend out of there if you can. Adding a resonator is a great idea to change the sound. Might try a different muffler designed to sound deaden VS a glass pack style muffler.The cherry bomb vortex isnt just a glasspack its also a magnaflow style muffler with glasspack inside. I havnt found a single thing on the internet of people having issues with drone and this muffler but all of those that I read people are using stock exhaust or bolt in exhaust(not custom). Also in my sig the car is on stock blown suspension but now Im on d2s with very little wheel gap. The exhaust cannot be brought up into the car any further since it nearly hits the underside of the car already. I scrape in the same spot everyone else here probably does, before the pipe bends to go to the muffler it hangs a little lower.http://i.imgur.com/qT3yJj7.jpg Edited October 30, 2014 by tankbob Link to comment Share on other sites More sharing options...
TexasQuest Posted October 31, 2014 Report Share Posted October 31, 2014 Chances are you need new exhaust studs from them stripping and pulling out. The gasket is probably fine. I replaced a couple studs at the firewall with bigger 10mm suds without changing the gasket and all I good. Link to comment Share on other sites More sharing options...
tsi_tom Posted October 31, 2014 Report Share Posted October 31, 2014 My manifold was not straight. I had the machine shop make it flat. Link to comment Share on other sites More sharing options...
ucw458 Posted October 31, 2014 Report Share Posted October 31, 2014 If you have the multi layer stainless steel gasket then it's re-useable. If it's the composite gasket it has to be replaced. I suggest fixing it now rather than later. It can affect O2 readings and possibly damage the engine over time. Link to comment Share on other sites More sharing options...
tankbob Posted October 31, 2014 Author Report Share Posted October 31, 2014 If you have the multi layer stainless steel gasket then it's re-useable. If it's the composite gasket it has to be replaced. I suggest fixing it now rather than later. It can affect O2 readings and possibly damage the engine over time.Im pretty sure I have the stainless gasket since it sticks out to cover the plugs a little(or maybe thats something else?). I havnt been driving the car very much but the exhaust manifold might be warped since its always been loud at the front of the car. So I have to pull it, possibly have a machine shop get it flat, and replace the bolts that hold it onto the head? Pretty sure DAD sells those ill go have a look, turbo has a little shaft play so hopefully I can take care of both at the same time once I can afford the turbo rebuild kit. Link to comment Share on other sites More sharing options...
ucw458 Posted October 31, 2014 Report Share Posted October 31, 2014 A little turbo side to side play is ok as long as it doesn't hit the housing. In and out play is bad. If your turbo is boosting fine you should be ok for now. Both gaskets cover the plugs a little. The MLS gasket has rivets and is quite sharp. A MLS gasket isn't likely to leak unless the manifold is warped. The composite gasket can leak just from getting the exhaust glowing during spirited driving. The material melts and blows out the side causing a leak. You don't have to replace the studs unless they are damaged. New locknuts would be advisable though. When you pull the manifold lay a straightedge across it to see if it's flat. MLShttp://www.enginemachineservice.com/ems/images/parts/conquest/gaskets/md102683.jpg Compositehttp://thumbs3.ebaystatic.com/d/l225/m/m_9PGm5ITSVkhn2TzbyhPVQ.jpg Link to comment Share on other sites More sharing options...
tankbob Posted October 31, 2014 Author Report Share Posted October 31, 2014 Mine looks more like the MLS but it has lots of little holes in it, how do I go about inspecting things to figure out exactly what needs to be replaced? Just start pulling the manifold off and go from there? Link to comment Share on other sites More sharing options...
ucw458 Posted October 31, 2014 Report Share Posted October 31, 2014 The MLS wont have holes in it. It will be a smooth finish vs the composite rough finish. Link to comment Share on other sites More sharing options...
tankbob Posted October 31, 2014 Author Report Share Posted October 31, 2014 The MLS wont have holes in it. It will be a smooth finish vs the composite rough finish.Ill have to get a better look tomorrow, thanks for all the help Link to comment Share on other sites More sharing options...
questtuner82 Posted October 31, 2014 Report Share Posted October 31, 2014 I have 3" on mine with the round flowmaster cat and a magnaflow muffler with dual outlet and sounds really well mannered Link to comment Share on other sites More sharing options...
questtuner82 Posted October 31, 2014 Report Share Posted October 31, 2014 Also if ur cat is hollowed out it can make a funky drone noise at certain rpms mine did when i had a hollowed out cat prior to the new exhaust Link to comment Share on other sites More sharing options...
Fuze Posted October 31, 2014 Report Share Posted October 31, 2014 (edited) On a few cars we've run glasspacks up front where the cat would be with 3" straight thru mufflers and the sound is nice and deep. Now, it's pretty loud still due to the straight thru muffler and glasspack but the frequencies you hear are cut down to mainly lower frequencies. The Mookeeh exhaust without the cats came with a resonator in the B-pipe instead of the cat. Of the ones I've run without a resonator, the sound is much harsher. Still havent found a combo that performs well and doesn't make you feel tired after long drives, that's the sacrifice! Now for the 90 degree bend, I assume that's right before the muffler... much better to have the muffler point towards the corner of the car and have a straighter path out. Have them start at the flange by the rear crossmember and come straight back and up... Edited October 31, 2014 by Fuze Link to comment Share on other sites More sharing options...
tankbob Posted November 2, 2014 Author Report Share Posted November 2, 2014 Also if ur cat is hollowed out it can make a funky drone noise at certain rpms mine did when i had a hollowed out cat prior to the new exhaustIve honestly got no idea if its gutted or not but it didnt drone even a little before with my apexi 4.5in tip fartcannon Link to comment Share on other sites More sharing options...
Recommended Posts