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Discussion Starter #1
Had some cracks on my 2003 V8 stock OEM center-exit exhaust. The cracks were in the muffler itself where the inlet and outlet pipes join it, and also on the inlet pipe near the sharp bend. Strangely enough only the left side pipes were affected, no cracks on the right side.

Simple job to remove and have it TIG welded, once I bought an electric impact wrench, the correct hex bit, and drilled out the inevitable siezed clamp bolt that sheared off. I don't think the muffler was ever previously removed in its 44k miles' life so far, so not a surprise.

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I was thinking of using this as an opportunity to upgrade to aftermarket exhaust, maybe something a bit less "muffling," or even straight pipes. But I was surprised to find the exhaust really wasn't much if any louder with the muffler removed, it just had a deeper tone. I had seen or heard somewhere the stock muffler is just a pass-through and this experience seems to support that theory. It does give the exhaust a different sound, guess I would say it's "sharper" for lack of a better term, but not appreciably quieter.

So I'll probably stick with the OEM muffler for now but I am still considering an upgrade from the current stock cats. Mine look to be in decent shape from what I can tell (see pics) so there's no hurry. But I am thinking less restrictive high-flow cats (200 cell maybe?) could sound better and maybe boost power a little. Don't want anything that would upset the ECU, O2 sensors, set OBD trouble codes, etc.

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Mostly an FYI here really, but...thoughts on any of the above??
 

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Wingless Wonder
1988 Esprit Turbo
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If you want to justify keeping the stock exhaust, remind yourself that supposedly it improves the aero at the back of the car.

(But if you REALLY want to improve drag, remove that rear WING from the hatch! There, I said it, as everyone expected me to! :giggle: :LOL::LOL: )



I don't think your butt dyno would feel any increased power from high-flow converters. You would do it only for the sound. I've helped early V8 owners install straight pipes and that mod works OK to make the exhaust more mellow.
 

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Discussion Starter #3
If you want to justify keeping the stock exhaust, remind yourself that supposedly it improves the aero at the back of the car.

(But if you REALLY want to improve drag, remove that rear WING from the hatch! There, I said it, as everyone expected me to! :giggle: :LOL::LOL: )



I don't think your butt dyno would feel any increased power from high-flow converters. You would do it only for the sound. I've helped early V8 owners install straight pipes and that mod works OK to make the exhaust more mellow.
Ha ha! So sad when wing envy rears its ugly head :sneaky:;)

Actually the primary reason I see to drop that muffler would be weight savings. Maybe if I could find a reasonably priced performance cat/straight pipe set I might be tempted...
 

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Had the same crack on my '04. Tried a custom made exhaust that included small magna flows; that was a mistake, then a set of stainless headers that produced a more euro exotic sound. Only thing it turned out they weren't really stainless steel so returned them. Then installed polished stainless free flow cats with the stock pipes and was happy. The stock muffler is a bit of a misnomer as it's an a empty can; more of a resonator.
 

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Discussion Starter #5
Then installed polished stainless free flow cats with the stock pipes and was happy. The stock muffler is a bit of a misnomer as it's an a empty can; more of a resonator.
Thanks. What brand/source for the free flow cats? Any CEL or OBD fault code issues?
 

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Thanks. What brand/source for the free flow cats? Any CEL or OBD fault code issues?
Sorry it's been too long for me to recall (10 years); the performance cats came from England and I had no code issues. They were really works of art; smooth mirrored finish with no visible welds. One of my original stock cats was empty and that didn't throw a code either. I remember someone was selling adaptors back then to fool the sensors when running straight pipes too. lotusespritworld.com is a good site for such info
 

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Similar problem on the earlier V-8 tail pipes, especially the R/H one. Must be some kind of vibration related resonance. Anyway, once welded up properly, it seems to last. The extra reinforcement of the welding is enough to do it.
David Teitelbaum
 

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Car Adicted
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David, so here is the deal.....I had an issue as it seemed one side of my exhaust wasn't blowing out as much as the other side. I had in the mean time bought a Cat delete pipe assembly and twin exhaust tips going out the back on my 98. Not the center exhaust. I pulled the Cats and the muffler, the muffler alone weighed 36 pounds, by memory. One of my cats had been.......well deleted by a previous owner and the other cat was broken inside clogged etc, so it was ........unclogged. The dual tips I bought from a Lotus member out in California were set up to bolt to the end of the cats. So get this......no muffler at all 36 + pounds saved and no Cats, just straight thru. The turbos muffle the exhaust sound.......for the most part until you get on it, but I am telling you this unleashed the beast. The turbos spool up super quick and it sounds great without sounding too loud. The guy down the street has a 570s McLaren and his son and him say that this sounds way better.....very nasty under full throttle. Get rid of the cats and buy some cat delete pipes at least with spacers for the O2 sensors. You will thank me and buy me a beer or 5 some day!!!! Trust me you have helped me quite a few times....take my advice and make the car what it can be. Mark Seifert
 

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I am in New Jersey and I still take the car through inspection. In this State they visually check the cats, communicate with the computer AND measure the tailpipe. If and when I go over to Historic plates I will be exempt from further emissions testing but til then I need working cats. I had a Tubi muffler on the car and it sounded bassier (is that a word?) but not louder. I prefer it not to get any louder by deleting the cats anyway. Clogged cats will definitely reduce your power but mine are working fine. I wouldn't mind losing 36 lbs but maybe if the driver lost it he would be better off rather than the car?
David Teitelbaum
 

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Discussion Starter #10
I did see these from PUK:


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Looks like beautiful workmanship but they are pricey, about $1730 USD and probably a fairly high shipping cost from UK.
 

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Car Adicted
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I get it. I have the historic plates here, so I am exempt. My car lost 36+ pounds the easy way.......now if the driver would lose some.
I am in New Jersey and I still take the car through inspection. In this State they visually check the cats, communicate with the computer AND measure the tailpipe. If and when I go over to Historic plates I will be exempt from further emissions testing but til then I need working cats. I had a Tubi muffler on the car and it sounded bassier (is that a word?) but not louder. I prefer it not to get any louder by deleting the cats anyway. Clogged cats will definitely reduce your power but mine are working fine. I wouldn't mind losing 36 lbs but maybe if the driver lost it he would be better off rather than the car?
David Teitelbaum
 
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