OEM Muffler Mod????

[COO86L]

I was actually going to get my own muffler delete made up, possibly even do it as an axle back cannon or something, but have it as V-Band clamps and change the stock muffler to suit so I can just swap it over with ease. Or butterfly that changes it to a dump straight down.
I just love the sound of the supercharger and stock catback sometimes

[gtpvette]

Originally Posted by ort895

+1 to find out if this ever materialized

I'm afraid not,,,, got side tracked after looking for a cheap local muffler for a while and not finding one. It's amazing the number of guys that want $200 for a used muffler.


I've got some time now,,, so let me look again. Still would like to do this.


As a sidebar,,, I've driven my FRS 25K miles this last year. A super little car. I'm shoping for springs and rims/tires now.

[gtpvette]

Lookie lookie....


https://miami.craigslist.org/brw/pts/5476017925.html

[gtpvette]

Originally Posted by gtpvette

Lookie lookie....


https://miami.craigslist.org/brw/pts/5476017925.html

Picked this one up today for $30,,,, let the fun begin. I've been thinking about how to do this,,, but no decision as of yet. Maybe the first pass I'll just keep it simple and see how it sounds.


If anyone has any ideas as to how these mods should go I'm all ears. Keep in mind it's a stock exhaust.

[Keenercarguy]

I can take a picture when I get home but a friend and I both just spaced out our mufflers a ways from the mid pipe. I have about an inch long gap there. Some gas still hits the muffler and at higher speeds it exhibits less drone than a track pipe. The degree of spacing affects both the acoustics and the volume.
A lot of people are probably thinking "you're an idiot and will melt your bumper or something" but my friend has one of the first FR-S' and has had it that way since just after purchase, with absolutely no issues whatsoever, sounds great too. We both intend to get really good aftermarket cat-backs (nameless is my intent) at some point and didn't see the point in spending limited college funds on something that wouldn't be very good (cheaply made aftermarket parts aren't fun).

ANYWAY to the brief tutorial.
Parts: further explanation in the steps
Two bolts at about 2.5 inches long
Two nuts of equal threads
2-6 quarter inch nuts for use as washers
A few regular washers for fine tuning the gap.
Two wrenches, I want to say that the OE nuts/bolts are 13mm but I'm not 100% sure and I am out of town at the moment so I can update later if necessary.

Remove the two bolts that connect the mid pipe to the muffler. You can jack the back left up for this and make it super easy, or you can just crawl under. Breaking everything loose is the only hard part of this whole process. Be careful to not strip the nuts, I could see someone doing that if they weren't a little careful.

Fetch some bolts of equal diameter (to OE) but about 2.5 inch length at a hardware store. If you're worried about them rusting or getting damaged get spares, I did but haven't used them in over a year of use so far.

Buy some nuts that are just barely larger in inside diameter to the outside diameter of your bolts, so that they can slide over the bolt but don't have too much play. These are your spacers; my friend used powder-coated spacers from his Legends racecar when he did his, so if you have those laying around too then more power to you. If you want things to be perfect than also grab a few regular washers so you can fine-tune your preferred sound.

While you have the muffler uncoupled, be sure to remove the gasket that sits between the two pipes, that *can* melt slowly over time, but won't hurt anything if it does (my friend didn't remove his and I did remove mine, his pipes are dirtier… he doesn't care).

Bolt everything back together with whatever spacing you choose, anything more than like an inch and a quarter starts to push the left exhaust tip out a tiny bit (noticeably): but you'll be approaching track pipe loud after that point anyway.

If you don't like it, oh no! You can just put it all back together in a few minutes.

Congratulations, you spent about $8 and don't need to chop up a muffler..?
I am curious how the chopping will go for you though!

Edit: Hope I didn't thread jack you too hard -_-'

[gtpvette]

Ok,, finally got around to cutting open the muffler. All cuts within the spot welds. I'm thinking I'll put a plate that covers the whole right side,,, and also cover the left side non-issue holes.


Cutting the pipes off was a bit of a problem. My 4.5" grinder/chop saw couldn't get in there. I ended up using a reciprocating saw to chop off the pipes. It was PITA.


I left a flap on the muffler skin as it'll make it easier to weld it up.


You'll notice in the first picture that internally those larger sections that run to the tips have perforations and sound absorbing material. Not a lot,, but some.


As a sidebar,, got my 949Racing 17x9 rims, BFG tires and Racecomp springs this week! Sweet.

[ort895]

keep it coming

[COO86L]

Originally Posted by Keenercarguy

I can take a picture when I get home but a friend and I both just spaced out our mufflers a ways from the mid pipe. I have about an inch long gap there. Some gas still hits the muffler and at higher speeds it exhibits less drone than a track pipe. The degree of spacing affects both the acoustics and the volume.
A lot of people are probably thinking "you're an idiot and will melt your bumper or something" but my friend has one of the first FR-S' and has had it that way since just after purchase, with absolutely no issues whatsoever, sounds great too. We both intend to get really good aftermarket cat-backs (nameless is my intent) at some point and didn't see the point in spending limited college funds on something that wouldn't be very good (cheaply made aftermarket parts aren't fun).

ANYWAY to the brief tutorial.
Parts: further explanation in the steps
Two bolts at about 2.5 inches long
Two nuts of equal threads
2-6 quarter inch nuts for use as washers
A few regular washers for fine tuning the gap.
Two wrenches, I want to say that the OE nuts/bolts are 13mm but I'm not 100% sure and I am out of town at the moment so I can update later if necessary.

Remove the two bolts that connect the mid pipe to the muffler. You can jack the back left up for this and make it super easy, or you can just crawl under. Breaking everything loose is the only hard part of this whole process. Be careful to not strip the nuts, I could see someone doing that if they weren't a little careful.

Fetch some bolts of equal diameter (to OE) but about 2.5 inch length at a hardware store. If you're worried about them rusting or getting damaged get spares, I did but haven't used them in over a year of use so far.

Buy some nuts that are just barely larger in inside diameter to the outside diameter of your bolts, so that they can slide over the bolt but don't have too much play. These are your spacers; my friend used powder-coated spacers from his Legends racecar when he did his, so if you have those laying around too then more power to you. If you want things to be perfect than also grab a few regular washers so you can fine-tune your preferred sound.

While you have the muffler uncoupled, be sure to remove the gasket that sits between the two pipes, that *can* melt slowly over time, but won't hurt anything if it does (my friend didn't remove his and I did remove mine, his pipes are dirtier… he doesn't care).

Bolt everything back together with whatever spacing you choose, anything more than like an inch and a quarter starts to push the left exhaust tip out a tiny bit (noticeably): but you'll be approaching track pipe loud after that point anyway.

If you don't like it, oh no! You can just put it all back together in a few minutes.

Congratulations, you spent about $8 and don't need to chop up a muffler..?
I am curious how the chopping will go for you though!

Edit: Hope I didn't thread jack you too hard -_-'

I really want to try this!!
How much gap did you have? About 1 nut width?
I need pictures. I'm going to try this on my other car.

[ort895]

Originally Posted by Keenercarguy

I can take a picture when I get home but a friend and I both just spaced out our mufflers a ways from the mid pipe. I have about an inch long gap there. Some gas still hits the muffler and at higher speeds it exhibits less drone than a track pipe. The degree of spacing affects both the acoustics and the volume.
A lot of people are probably thinking "you're an idiot and will melt your bumper or something" but my friend has one of the first FR-S' and has had it that way since just after purchase, with absolutely no issues whatsoever, sounds great too. We both intend to get really good aftermarket cat-backs (nameless is my intent) at some point and didn't see the point in spending limited college funds on something that wouldn't be very good (cheaply made aftermarket parts aren't fun).

ANYWAY to the brief tutorial.
Parts: further explanation in the steps
Two bolts at about 2.5 inches long
Two nuts of equal threads
2-6 quarter inch nuts for use as washers
A few regular washers for fine tuning the gap.
Two wrenches, I want to say that the OE nuts/bolts are 13mm but I'm not 100% sure and I am out of town at the moment so I can update later if necessary.

Remove the two bolts that connect the mid pipe to the muffler. You can jack the back left up for this and make it super easy, or you can just crawl under. Breaking everything loose is the only hard part of this whole process. Be careful to not strip the nuts, I could see someone doing that if they weren't a little careful.

Fetch some bolts of equal diameter (to OE) but about 2.5 inch length at a hardware store. If you're worried about them rusting or getting damaged get spares, I did but haven't used them in over a year of use so far.

Buy some nuts that are just barely larger in inside diameter to the outside diameter of your bolts, so that they can slide over the bolt but don't have too much play. These are your spacers; my friend used powder-coated spacers from his Legends racecar when he did his, so if you have those laying around too then more power to you. If you want things to be perfect than also grab a few regular washers so you can fine-tune your preferred sound.

While you have the muffler uncoupled, be sure to remove the gasket that sits between the two pipes, that *can* melt slowly over time, but won't hurt anything if it does (my friend didn't remove his and I did remove mine, his pipes are dirtier… he doesn't care).

Bolt everything back together with whatever spacing you choose, anything more than like an inch and a quarter starts to push the left exhaust tip out a tiny bit (noticeably): but you'll be approaching track pipe loud after that point anyway.

If you don't like it, oh no! You can just put it all back together in a few minutes.

Congratulations, you spent about $8 and don't need to chop up a muffler..?
I am curious how the chopping will go for you though!

Edit: Hope I didn't thread jack you too hard -_-'

some sound clips would be much appreciated.

[gtpvette]

Ordered a couple of these from ebay this AM,, $7 shipped. They're galvinzed post caps with a 2.5" ID. These should slip over the open unused pipes and I'll put a couple of tacks on them to keep them in place.


As a sidebar,,, anyone ever use a Decibel App on the Iphone??

[turbocat]

Originally Posted by gtpvette

I'm wondering if anyone has cut open and modded the OEM muffler for a more robust sound?? This is something part of the C6 Z06 guys do and it works pretty well,, and doesn't really cost anything if you have a welder.

I found a video on youtube where a guy cut a muffler open. I'm thinking just cut part of the pipes off to allow a more direct path and maybe seal off the perforated section on the input. Thoughts???

Z06 Muffler Mod Instructions

http://www.sccorvettes.org/Portals/0...z06muffmod.pdf

I wanted to reply to this because I have a similar mindset. I've always modified my cars with the OEM Plus mindset. Along this line of thinking this is what I did for my BRZ. My brother in-law had a 2nd gen TC. It had a really nice low mellow exhaust note. I stuck my head under his rear bumper and started formulating a plan.

I purchased a used OEM stock Axel Back from a Scion TC 2nd gen. Its a Stainless Steel spun case form, Bullet type muffler. It is straight through design. It is also considerably lighter than the Stock muffler. I flipped it over to fit our cars exhaust configuration. I cut off the TC inlet pipe. Welded on a section of 90* SS pipe, and a new 2 bolt flange. Then added two exhaust hangers to fit up to two of the stock locations. Its still a work in progress, and my welds are ugly. Im still deciding on an exhaust tip. It sounds really good. Low mellow tone, no rasp, no drone.

[Keenercarguy]

Originally Posted by COO86L

I really want to try this!!
How much gap did you have? About 1 nut width?
I need pictures. I'm going to try this on my other car.

My car is in the shop for a week for warranty work, so pictures will have to wait. I used two nuts and two washers on each side though IF I remember correctly.

@ort895. I can take a sound clip with my iPhone once I pick the car up, but unfortunately I don't have a real mic of any kind.

Sorry OP for the thread jack, and I bet you'll love the RCE Springs!

[ort895]

Originally Posted by gtpvette

Ordered a couple of these from ebay this AM,, $7 shipped. They're galvinzed post caps with a 2.5" ID. These should slip over the open unused pipes and I'll put a couple of tacks on them to keep them in place.


As a sidebar,,, anyone ever use a Decibel App on the Iphone??

Apparently they don't really work that well

[gtpvette]

Originally Posted by Keenercarguy

Sorry OP for the thread jack, and I bet you'll love the RCE Springs!

No worries,,, the more the merrier. It's a pretty clever solution you came up with BTW. I've got a couple of projects around the house to finish before the springs go in,, so it'll be a couple of weeks before I have time. Happy wife = happy life.




TURBOCAT,,, nice work on the refit. That's just a flow through with perforated tube and some type of sound suppressor I guess?? Makes me think I should cover all the holes in the baffles on mine. I picked up a small lightweight steel plate at Home Depot last night for $10 that will make the baffle covers. I'll try to cut it to fit tonight. I'm $47 into this at this point. $3 more and I'm over budget