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Exhaust

Empirecrzy241

New member
Hey, just got around to thinking about putting some new mufflers on the GP the other day and I'm thinking Thrush Turbos. One thing however, can I just cut out the stock mufflers and clamp the new ones up or do I have other things to consider? Also, what inlet/outlet sizes do I need for stock exhaust system?
 


u cannot just cut off the mufflers and clamp on new ones. welding is needed. exhaust shops don't charge too much to put on mufflers. you need a 2.25" inlet and a 2.25"-2.50" outlet depending if u get different tips or not.

even with a 2.25" inlet, the shop will have to put on a small adapter because the y piping is actually smaller than 2.25". we had to do this on mine
 
u cannot just cut off the mufflers and clamp on new ones. welding is needed. exhaust shops don't charge too much to put on mufflers. you need a 2.25" inlet and a 2.25"-2.50" outlet depending if u get different tips or not.

even with a 2.25" inlet, the shop will have to put on a small adapter because the y piping is actually smaller than 2.25". we had to do this on mine

Actually you want to clamp on the muffler, it will wear out before the piping.
 


weld it, its the proper way.

clamps work well, but will still be just as difficult to get off, if not impossible since it permanently bends the metal and lodges it inside then rust welds itself together.
 
weld it, its the proper way.

clamps work well, but will still be just as difficult to get off, if not impossible since it permanently bends the metal and lodges it inside then rust welds itself together.

I can have mufflers that where clamped on off in less then a min. When we do a custom exhaust at work all the pipe on pipe joints are welded then mufflers are clamped.
 


You wont be disapointed with the Magnaflow Catback. Thats what I have had for several years now. At first I tried the Thrush and Afterburner mufflers. Too raspy/ricey for my taste. I got mine from Hottexhaust.com . I paid $645.00 but now the kit is $850.00.
 
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gmpartsdirect.com-I bought my system below from them and like stated above it is terrific and a true magnaflow system for $450-All stainless steel-you cannot beat the price! The system below is a maganflow system and all the mufflers and resonator have "magnaflow" embossed on them! They cannot advertise it as a magnflow system for that price!
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124986171.gif
GM PART # 12498617

CATEGORY: All
PACK QTY: 1
CORE CHARGE: $0.00
GM LIST: $630.00
OUR PRICE: $458.64

DESCRIPTION: W-body Exhaust Package For use on 1999-2004 Chevrolet Monte Carlo; 2000-2004 Chevrolet Impala; 1997-2003 Pontiac Grand Prix. This replacement exhaust system is constructed with 409 stainless steel tubing and 304 polished stainless steel muffler and tips. Four Inch tips exit under the rear bumper and have adjustable depth to accommodate both stock bumper and ground effects kits. Exhaust adds a throaty rumble while still maintaining a palatable interior noise level. Cars not orginally equipped with dual exhaust will need the dual exhaust conversion kit 12498653 (sold seperately)



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NOTE: GMPartsDirect.com carries 380,000 GM parts. Due to the number of parts available, the part you are searching for may not appear in these results. Please use our Customer Service page if you need help locating a GM part. Can’t find a part?^ Back to Top ^
 
I had that GMPP exhaust on my car, had to put the stock mufflers back on except for the resonator. I bet your wondern why?

Dean

Drone-That's the difference between a 60 degree V6 and a 90 degree V6-no drone in the 3.1. The 3.8 sounds pretty nasty with most aftermarket mufflers unless it's perfectly matched to the owners taste in many GP owner's opinions. I had a 98 GT with the stock exhaust system and have the GMPP on my 01 GP SE-i like the way it sounds.

PS-All I am saying is if someone wants a magnaflow system, GMPP direct is the best price by far-if you don't like the magnaflow system so be it! Pick something else.
 


I dont seem to have the drone with my system. Heck at 60mph I barely hear the exhaust. When new it was noticably louder at slow speed. Like as driving around in a parking lot. My girlfriend gave me a bunch of s**t about my "upgrade". Not shure if I have got used to it or not, but I swear it isnt as loud as when it was new. It still has a sweet rumble and tone. I get complaments from people all the time. Really the only difference I can see between the pic above and my system is that my system has dual outlet tips that were welded on the mufflers from Magnaflow, and my mufflers are a bit more oval shaped.
 
I dont seem to have the drone with my system. Heck at 60mph I barely hear the exhaust. When new it was noticably louder at slow speed. Like as driving around in a parking lot. My girlfriend gave me a bunch of s**t about my "upgrade". Not shure if I have got used to it or not, but I swear it isnt as loud as when it was new. It still has a sweet rumble and tone. I get complaments from people all the time. Really the only difference I can see between the pic above and my system is that my system has dual outlet tips that were welded on the mufflers from Magnaflow, and my mufflers are a bit more oval shaped.

I agree with you that my magnaflow system does not drone and was louder when new but coming up on 1 year now has quieted down quite a lot. Basically, my system has a deep rumble at low RPM's but is fairly quiet and can be heard at highways speeds but it is not obnoxious at all, low tone. Lot's of people on the forum trash the magnaflow system but exhausts are very subjective to the owners so really not surprising.

The GMPP system is a GENUINE magnaflow cat back system with 4 inch round stainless steel tips versus the dual quad tips sold elsewhere for the GP's. I have heard that Magnaflow offered 2 systems for the GP's and the later system may be quieter than my exhaust (it can't be by much) had the quad tips but we are talking $458 for the GMPP system versus around $800 for the dual quad tip system. You decide if that much of a difference in price is worth it!
 
Thats right, DRONE! At 1800-2300 cruising down the raod or highway, the rpm the engine operatesit the most is when it was the loadest, gave me headaches. I liked the sound at idle and everywhere else, except at that rpm range, after awhile it got old, very old.

Dean
 
Actually, I was thinkin about glasspacks, but I guess I really don't know what they would sound like on a GP. Anyone have any experience with them? If not those, I think I might go with Thrush Dynomax super turbos. Thoughts?
 
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