Mufflex 4" catback is huge!
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From: Prince George, BC, Canada
Car: 89 GTA
Engine: 5.7L Supercharged
Transmission: T-56
Axle/Gears: Moser 9" 3.70
Mufflex 4" catback is huge!
Wow must say I'am going to really need a serious engine to get any use out of this catback, this is just sick lol
I went with the single pipe out the back with a spintech muffler, here are some pic's out of the box and trust me it's just huge these pic's don't do it justice.








I went with the single pipe out the back with a spintech muffler, here are some pic's out of the box and trust me it's just huge these pic's don't do it justice.








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From: Minnesota
Car: 89 IROC-Z
Engine: 370 LSX, LS3 Top End
Transmission: Built T-56
Axle/Gears: 9" Aluminum Center 3.89's
Re: Mufflex 4" catback is huge!
looks like there should be a diesel in there with that size of pipe. our 300 horsepower tractors only got a 5 inch pipe
not bashing you i bet it will sound awesome
not bashing you i bet it will sound awesomeJoined: Sep 2003
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From: Pittsburgh PA
Car: 89 Iroc-z
Engine: 555 BBC Turbo
Transmission: TH400
Axle/Gears: MWC 9” 3.00
Re: Mufflex 4" catback is huge!
nice, should compliment your motor nicely. 4" is good for 375-400+whp motors. A blown motor is easily capable of near that
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From: Ottawa, ONT
Car: 1987 Firebird
Engine: 355
Transmission: T56
Re: Mufflex 4" catback is huge!
First thing i did when i got my 3.5" cutout was marvel at how huge it was by sleeving it over my arm!!! I can imagine 4" would be even more amazing. They are absolutely huge.
Re: Mufflex 4" catback is huge!
Damn that looks good! You have to post a sound clip of this once you get it installed. May I ask how much that cost? I'd want the dual tip version, 82351C-DT. My current system consists of Hooker shorties, custom 3" ypipe, 3" ipipe to my SLP "Bullet" mouth. I have yet to hear it on my 383 though
Next year I'll be popping for some LT's.
Next year I'll be popping for some LT's. Last edited by Demon355; Aug 17, 2008 at 03:20 AM.
Thread Starter
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iTrader: (7)
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From: Prince George, BC, Canada
Car: 89 GTA
Engine: 5.7L Supercharged
Transmission: T-56
Axle/Gears: Moser 9" 3.70
Re: Mufflex 4" catback is huge!
Worked out to be $760 or so canadian with all costs included. I was thinking of getting the duel tip version but eh i'am kind of the guy that likes to keep it a sleeper all though after the heads/cam and new exhaust goes in she is going to be sounding probably pretty loud lol. Hopefully my stock bottom end with take the abuse for a bit but if not I'll have to build a shortblock that will take my 600+ rwhp goal.
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From: Houston, TX
Car: 1989 GTA
Engine: SuperRam 350
Transmission: Pro Built S/S TH700R4
Axle/Gears: 3.27
Re: Mufflex 4" catback is huge!
What a brute!
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Sleeper? You call long tube headers and a 4" catback a sleeper? You'll be recording numbers on the richter scale.
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Worked out to be $760 or so canadian with all costs included. I was thinking of getting the duel tip version but eh i'am kind of the guy that likes to keep it a sleeper all though after the heads/cam and new exhaust goes in she is going to be sounding probably pretty loud lol. Hopefully my stock bottom end with take the abuse for a bit but if not I'll have to build a shortblock that will take my 600+ rwhp goal.
Last edited by Reid Fleming; Aug 17, 2008 at 12:29 PM. Reason: Automerged Doublepost
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From: Louisville Kentucky U.S.A.
Car: 86 Iroc Z
Engine: 406
Transmission: 350 Turbo
Axle/Gears: 373
Re: Mufflex 4" catback is huge!
Looks like you bought the exact same kit I did. I love mine and you won't believe the clearence you get.
Click the link in my sig to hear.
Click the link in my sig to hear.
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From: Chicago
Car: 1999 Jeep Grand Cherokee
Engine: 4.7l PowerTech V8
Re: Mufflex 4" catback is huge!
wow that is freakin huge haha
---------------------------------
by the way, 1FastZ, your car just made me get a woody that sounds amazing
---------------------------------
by the way, 1FastZ, your car just made me get a woody that sounds amazing
Thread Starter
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iTrader: (7)
Joined: Jul 2000
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From: Prince George, BC, Canada
Car: 89 GTA
Engine: 5.7L Supercharged
Transmission: T-56
Axle/Gears: Moser 9" 3.70
Re: Mufflex 4" catback is huge!
Your car sounds pretty good thanks for the link!
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From: Louisville Kentucky U.S.A.
Car: 86 Iroc Z
Engine: 406
Transmission: 350 Turbo
Axle/Gears: 373
Re: Mufflex 4" catback is huge!
I went from true duals to this so I gain tons of clearence. I don't have to worry about speed bumps anymore lol
Joined: Sep 2003
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From: Pittsburgh PA
Car: 89 Iroc-z
Engine: 555 BBC Turbo
Transmission: TH400
Axle/Gears: MWC 9” 3.00
Re: Mufflex 4" catback is huge!
with stock tranny crossmember or T56, you'll have good clearance with either y pipe for longtubes or shorties
with shorty headers and spohn crossmembers, you will have good clearance with ypipe like stock
with longtubes however, spohn crossmembers (and possibly other designs)will not allow the mufflex y pipe to work.
with shorty headers and spohn crossmembers, you will have good clearance with ypipe like stock
with longtubes however, spohn crossmembers (and possibly other designs)will not allow the mufflex y pipe to work.
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From: Prince George, BC, Canada
Car: 89 GTA
Engine: 5.7L Supercharged
Transmission: T-56
Axle/Gears: Moser 9" 3.70
Re: Mufflex 4" catback is huge!
Right now I'am running a Spohn t-56 crossmember with torque arm but I'am changing that to Skulte Performance t-56 Longtube Crossmember for the extra space for the pipes. Not sure what I'am going to do with the torque arm though, I might put back the stock piece or go with something else like the BMR one.
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From: Elk City OK
Car: 92 25th anv z28
Engine: 346 TC78 Turbo
Transmission: 4L80E
Axle/Gears: 3.25 9"Nodular, Strange axles
Re: Mufflex 4" catback is huge!
Same kit as me! Still working on the install. I built by own Y. Its dual 2.5" pipes into the 4". Had to fab my own down pipes from the manifolds of my LS1 to the exaust.. Allmost done. Post some sound clips!
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Car: 1987 Camaro SC, 1999 Z28
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Joined: Jul 1999
Posts: 900
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From: Haslett, MI
Car: 1984 Trans Am WS6
Engine: Minirammed 385, 396 RWHP
Transmission: T56
Axle/Gears: 3.73 Moser 12-bolt
Re: Mufflex 4" catback is huge!
Right now I'am running a Spohn t-56 crossmember with torque arm but I'am changing that to Skulte Performance t-56 Longtube Crossmember for the extra space for the pipes. Not sure what I'am going to do with the torque arm though, I might put back the stock piece or go with something else like the BMR one.
You might want to try going back to the stock location but with polyurethane bushings and a tubular adjustable torque arm. Or, if you dare to be different, try Unbalanced Engineering's decoupled torque arm! It works great on the road course but involves fabrication and welding.... The payoff is unrivaled under-car clearance. In fact, my lowest part of the exhaust system is the Hooker LT collector. It's all uphill from there!
Joined: Sep 2003
Posts: 25,895
Likes: 429
From: Pittsburgh PA
Car: 89 Iroc-z
Engine: 555 BBC Turbo
Transmission: TH400
Axle/Gears: MWC 9” 3.00
Re: Mufflex 4" catback is huge!
weld the spohn mount to the skulte member
Last edited by Orr89RocZ; Aug 20, 2008 at 06:08 AM.
Thread Starter
Supreme Member
iTrader: (7)
Joined: Jul 2000
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From: Prince George, BC, Canada
Car: 89 GTA
Engine: 5.7L Supercharged
Transmission: T-56
Axle/Gears: Moser 9" 3.70
Re: Mufflex 4" catback is huge!
That's a idea but I'am think I'am just going to sell it.
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