Reducing Rasp or Loudness
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Teching In
Joined: Jun 2005
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From: Daytona Beach, FL
Reducing Rasp or Loudness I'm deciding on what to do with the long tube, ory, loudmouth setup I have...like many others. Just a little confused on what reduces what. If cats are installed, will the end result reduce more rasp or volume than a muffler-type would? Or would a muffler do a better job of reducing rasp?
I just swapped out my Sweet Thunder Rumbler catback out for a Hooker. they didn't have any 3" pipe left so now I have a Hooker catback with a Sweet Thudner in the I-Pipe. It's insanely quiet even with LTs and ORY that I have. 3" straight pipe for the I-pipe is coming in 2 days... should waken her up a bit 
TECH Addict
Joined: Jun 2005
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From: England
Originally Posted by FHAWKer
I'm deciding on what to do with the long tube, ory, loudmouth setup I have...like many others. Just a little confused on what reduces what. If cats are installed, will the end result reduce more rasp or volume than a muffler-type would? Or would a muffler do a better job of reducing rasp?
The easy option is to replace the LM resonator with a glass pack straight thru bullet muffler such as Magnaflow, Borla, Dynomax, etc. Now bear in mind the muffler you fit will not contain much packing due to the limitations of space under the car. This approach should alter the sound and hopefully reduce rasp but overall volume, as in db will remain pretty much the same.
Something else to bear in mind, the TSP Rumbler exhaust is basically a Dynomouth. It uses a Dynomax bullet muffler. People still complain about rasp and drone with it, so adding such a muffler to a LM maynot be the best answer. Personally I think the Magnflow muffler sounds the best and it's cheaper than a Borla XR-1.
However as a personal view I actually prefer the sound of the LM resonator. Adding CATS should also reduce the rasp but probably won't affect the tone quite as much as a muffler swap. It should also have a greater affect on noise reduction, but do remember the LM is LOUD even on stock CATS/headers so it will never really be that quiet. LT's with a catted Y should make the LM sound very similar to what it does on a stock setup in terms of tone and loudness.
For me I'd just run CATS but being in the UK it really isn't an option not too. Although good CATS won't really affect performance/hp on a bolt on/cammed car. If you want to keep your ORY swap in a Magnaflow muffler - but it will still be loud.
Final option is a different catback, which really leaves you with limitless options. However if you like the ruff OTT sound of the LM I personally feel the Hooker would be a bit of a dissapointment.
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Joined: Jun 2005
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From: England
Depends what you define as RASP?
I've listen to ALL of the clips on LS1sounds.com with the LM and only a couple appear to have any rasp. I would also say my z/28 running a LM also seems completly rasp free but I'm sure someone would say otherwise.
I've listen to ALL of the clips on LS1sounds.com with the LM and only a couple appear to have any rasp. I would also say my z/28 running a LM also seems completly rasp free but I'm sure someone would say otherwise.
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I had the LM catback and the sound was good but too much drone and rasp. I pulled the resonator and threw in a moroso spiralflow bullet and that helped quiet things down and made the rasp/drone decrease...a little bit.
I then put on QTP LT's, Ypipe w/ high flow cats and that made the rasp go away almost totally and there is no more drone on the highway and the thing sounds like an old muscle car...I love it.
I then put on QTP LT's, Ypipe w/ high flow cats and that made the rasp go away almost totally and there is no more drone on the highway and the thing sounds like an old muscle car...I love it.
TECH Addict
Joined: Jun 2005
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From: England
Originally Posted by FHAWKer
What magnaflow muffler are ppl using in place of the LM resonator?
Check out Magnaflows website or Summit. A 6" round muffler should have more silencing affect but I think you might be tight on space without it fowling the propshaft.
