1st Generation Specific (1979-1985) 1979-1985 Discussion including performance modifications and technical support sections

New RB muffler is crooked

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Old Jul 18, 2009 | 09:37 PM
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New RB muffler is crooked

I just installed a new Racing Beat muffler on my car today (84 GSL-SE) and the install was relatively painless thanks to air tools, bolt extractors, and PB Blaster, but when i had everything back together the muffler tips weren't even. I loosened the hanging bolts and tried to manhandle the muffler to be straight, but naturally the rubber hangers just moved wherever they wanted to do. So I wanted to know, is there anything I can do to adjust this? Or am I just being OCD?



Now, I didn't replace the muffler hangers. "Aha!" you might say. But, the problem to me doesn't seem like left side is sagging, instead it looks like the right side is actually up too high. The right tip is almost touching the metal of the car, and the left tip is more like where I would think the tip should be. If it is the hangars, I wanted to check here first, since the car uses a lot of them and they are expensive!

Installation notes: I had previously installed a RB header and presilencer, today I finally trashed the stock muffler and put the RB one on. I didn't touch any of the mounting hardware, I only unscrewed the nuts connecting directly to the muffler. I didn't do anything else to the car except for vacuuming the interior.

Unrelated impressions of muffler for anyone who cares (skip the book if you don't care) : I couldn't afford the whole system at once and my exhaust manifold was leaking badly, so I ordered the single outlet header/presilencer combo and have had it on the car for about a month. However, the car was freaking LOUD, and I don't like loud.

Sound: The muffler made the car VERY quiet, probably quieter even than my stock exhaust with cats and burned up muffler. Like all the other RB systems I've had it really wakes up above 3000 rpms though. I'm pretty sure it's not even as loud as my Miata with a RB muffler and stock everything else. With the car idling, I could stand behind the car and still hear the fans and pulleys turning from the engine bay with the hood closed. Inside of the car, I can hear the exhaust but I can also hear the roar of my cone hot-air-intake. It sounds awesome, even if it's not really making power

Power: I actually LOST a tiny bit of power, I think. My theory is that my old stock muffler's internals were burned up long ago, so it was basically a straight through muffler. It surely didn't do any actual muffling. However, the power delivery is much better, and is consistent through the entire RPM range.

Weight: The RB muffler is quite a bit heavier than the stock muffler. It's also HUGE, but I suppose it needs to be. I don't consider this a problem since the overall RB system is much lighter than stock since the exhaust manifold and the cats are a lot heavier than the header and presilencer.

Looks: The tips look much better in person than it looks in any of the pictures I have seen. I do wonder why the rest of it is painted black when all other RB stuff is chromed. Not that I care.
Attached Thumbnails New RB muffler is crooked-crooked-muffler.jpg  
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Old Jul 18, 2009 | 09:49 PM
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I like to leave the flange nuts tightened loosely until the hangers are all bolted in place. After everything is aligned I tighten the 2) muffler to exhaust pipe flange bolts. You can get the flange connection twisted slightly, causing the crooked tail pipe look you show. A broken or missing hanger rubber can cause this also.
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Old Jul 18, 2009 | 10:33 PM
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could you record a video of the sound of the exhaust? i'm thinking about what to do to improve my exhaust. and i'd love to hear what it sounds like on an se, if it is any different from a 12a....
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Old Jul 18, 2009 | 10:56 PM
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make sure you didnt bend the muffler bracket. its the part that the two rubber hangers bolt to. it bolts to the underside of the car via two 12mm bolts. often times the ears are weakened by rust and bend, causing the muffler to lean to one side or the other.
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Old Jul 18, 2009 | 11:18 PM
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74 RX7: I actually bolted it the other way. I tightened the flange bolts first, then the hanger bolts afterwards. I'll undo them all and try again.

thunkrd: I'll see if I can remember to do that tomorrow. My digital camera has a movie mode with sound, but I've never used it, I don't know how good it is.

mazdavert: Good idea. I didn't think about it before but the bracket is made of thin metal, I could have easily bent it when trying to get the old rusty bolts off and not noticed.

Thanks guys!
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Old Jul 19, 2009 | 12:49 AM
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keep us posted with what you find. i would not be completely satisfied with the install either with it sitting a touch crooked.
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Old Jul 19, 2009 | 06:22 AM
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I also have the same problem, except it's a pacesetter muffer that the previous owner installed.

Interested in results of this thread.
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Old Jul 19, 2009 | 05:51 PM
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Here is the first vid, taken from inside my car. Pardon my lack of driving skills, I'm holding the camera in my left hand so you can see what RPM I'm running at. Play at a low volume, the camera's mic picked up every little sound, including some my human ears can't hear, and it makes the car sound louder than it really is.

http://www.youtube.com/watch?v=CE1X2lwy2gs

I have a second video taken from outside the car, but my license plate is right in the middle of the shot. I don't know how to edit video, so I'm trying to figure out how to blur the plate so I can put it up.

As far as the crookedness goes, I loosened up the three mounting bolts, and realized part of my problem. When torquing the bolts, it actually moved the mounting hardware's position a bit. I was a bit more careful and got it finger tight, then used the wrench to finish torquing. It's just mounting, it doesn't require gorilla strength. It is just about perfect, but I can probably get it slightly better if I loosen the flange bolts too like 74RX7 recommended. I did this in the driveway without jacking the car, so I couldn't reach the flange bolts.

*edit*
Second video:

http://www.youtube.com/watch?v=iQecAulO7Wk

I didn't really mean to bury the tach in the redline, I usually max at 7k rpms. Oops.
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Old Jul 19, 2009 | 11:17 PM
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Sounds about normal for the RB exhaust. I would be more concerned about the oil pressure gauge. I personally think the RB system sound better without the presilencer.
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Old Jul 20, 2009 | 07:56 AM
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Yeah, the oil pressure gauge hasn't worked since I got the SE. It's on my "to do" list.
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Old Jul 20, 2009 | 09:06 AM
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i'd get that fixed right away. look and make sure the wire (yellow with red stripe) with blade type connector is plugged onto the oil pressure sender. if it is, check for breaks in the wiring and maybe even test the gauge itself. if those are good, replace the sender.
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