LMS muffler question

[dnsherrill]

when I re-did the fact exh on my brown car I had the 3rd cat and resonator removed. They put 2.5'' duals with no x-over or h-pipe into flowmaster 40's. It was loud and raspy. new pipes are louder than old pipes. I later added an x-pipe mid body and it's still loud but it breathes much more evenly; it sounds like balanced pressure.
imo the 'drone' occurs at certain frequency levels that correspond to different rpm ranges. This can vary from person to person; for me it's around 12-1500 rpms. A baffle the right length (attached to the exh pipe) can mute the drone based on wavelenghts (Hz).
I just picked up some magnaflow xl's and may replace then sell/trade the 40's since I will be driving the brown car about 3 hrs/day 5x week. The mf's should be less loud than the 40's
for the exh i paid 250 and i provided muffs
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my $0.02
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another exh thread, 4 pages of jibba-jabba

 

[95mark8newyork]

You don't need real duals for it to be loud. My dad had a custom exhaust made, single to dual from the stock Y pipe with original 2 chamber flowmaster 40s. At idle it was beefy, driving around, hard accel and WOT was ridiculous. Might not be holy **** loud like a car with headers and no cats, but for basically stock it sounded pretty nasty. Look for some used Flow 40 original 2 chambers, throw em on and take the resonator off.

 

[95mark8newyork]

Question...
The dual growling sounds from the infinity G series, is it due to the mufflers or factory exhaust piping?

More so the engines themselves. I myself love the way infiniti's sound from the factory, they do something with those motors that give them a clean and pretty nice exhaust note.

 

[stormfinder]

ah, geez just be like me, 04 cobra manifolds, 04 cobra offroad x-pipe from summit racing.

(actually dont, cause right now i have that nice pretty 04 cobra xpipe flowing right back into a y pipe into the base exhaust, haha)

But when i get more funds, i will be having another x added, mandrel bent pipe, and some good mufflers.

 

[MN12hybrid]

On my 92 Tbird (3.8 NA slug) I installed a true-dual setup with Magnaflow (straight flow) mufflers and high flow cats and deleted the resonator. It made it loud but it had the raspy sound, almost like a ricey Honda sound. I eventually got an x-pipe in there in the spot where the resonator originally went, and it was still loud, but sounded WAY better - it was deep, the raspy sound was gone and everybody was complimenting me on the exhaust after. It also made a noticeable difference with torque at low to mid range RPM's.

I eventually got a 93 Tbird (5.0) and I moved the whole exhaust (without the high flow cats) over, and it sounded wicked! It was deep, loud, and once the mufflers (and the car) warmed up it was even louder. I noticed it was louder on cold days as well. There was a very loud and deep drone on the freeway when in overdrive, around the 60-75 mph range especially. It was so overwhelming that it made it impossible to talk on the phone when on the freeway, and caused countless arguments with my girlfriend.

On both MN12's with the exhaust setup, I never had an issue smogging them and this is in Los Angeles - Cali is the worst place to be for this kind of thing. The exhaust was not mandrel bent though.

I want to eventually create a similar setup for my Mark - I cant help but wonder if the same exhaust (that was on my Tbird) would be louder than the Mark. Im not certain, but I think you can delete the 3rd cat without causing any issues as long as you leave the other 2 on there. When I do this for my Mark, I am going to try mandrel bent pipes this time.