4" mufflex exhaust
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From: Ne Pa
4" mufflex exhaust is anyone here running this exhaust.
i have a 395 stroker and was wondering if i would see any gain going from a loudmouth to this setup.
i have a 395 stroker and was wondering if i would see any gain going from a loudmouth to this setup.
Teching In
Joined: Jan 2004
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im not for sure about 4" exhaust on a stroker but i have been told on any ls1 based motor over 3 " is a waste and you might loose power. i read in a magazine posted by slp that the motor likes a little back pressure to funtion right. so if it were me i'd go with 3". but thats my opinion. 
yes it needs some back pressure, but that's what a muffler is for.
i have the 4" with the spintech muffler and dual exits and a cutout back by the muffler. it sounds awesome through the muffler and i can open the cutout when needed to bypass the muffler.
by the way, don't be a magazine racer please.
i have the 4" with the spintech muffler and dual exits and a cutout back by the muffler. it sounds awesome through the muffler and i can open the cutout when needed to bypass the muffler.
by the way, don't be a magazine racer please.
I really dont see you losing any power with a 4" CATBACK
its not like your running 4" duals dude
I think a 4" single pipe is the equivelant of 2.25" duals, when considering airflow
its not like your running 4" duals dude
I think a 4" single pipe is the equivelant of 2.25" duals, when considering airflow
A single 4" is almost the equivelant of dual 3" pipes (dual 3" are actually equivelant to a single 4.25").
I'm running the 4" Mufflex setup on my h/c car and it doesn't seem to make the power that cars with a set of good true duals with an X-pipe do... (G5X2 cam, S2 LS6 heads; 440 RWHP). There are other possible issues with my car (possible valvetrain adjustment issues; I am running the Schubeck lifters), though. Torque seems to be down a bit, too (410 RWTQ).
I was originally running the Spintech single outlet muffler, but lost 20-25 RWHP across the band vs. open headers (443 w/ open headers, ~415-418 through the Mufflex/Spintech). I replaced the Spintech with a 5" Borla XR1 (had Burns Stainless make me up some 4" to 5" adapters), and gained damn near all of the lost power back (only lost 3 RWHP through the exhaust).
I'm not saying that it won't work for you, only that in my case it doesn't work as well as I had hoped.
I'm running the 4" Mufflex setup on my h/c car and it doesn't seem to make the power that cars with a set of good true duals with an X-pipe do... (G5X2 cam, S2 LS6 heads; 440 RWHP). There are other possible issues with my car (possible valvetrain adjustment issues; I am running the Schubeck lifters), though. Torque seems to be down a bit, too (410 RWTQ).
I was originally running the Spintech single outlet muffler, but lost 20-25 RWHP across the band vs. open headers (443 w/ open headers, ~415-418 through the Mufflex/Spintech). I replaced the Spintech with a 5" Borla XR1 (had Burns Stainless make me up some 4" to 5" adapters), and gained damn near all of the lost power back (only lost 3 RWHP through the exhaust).
I'm not saying that it won't work for you, only that in my case it doesn't work as well as I had hoped.
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Joined: Apr 2002
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From: Murrieta
I have a Mufflex 4" with the a Magnaflow muffler in place of the Flowmaster. The car made the same power through the exhaust as it did through dual 3" cutouts, and about 25rwtq more under 4k. And it's quiet enough to drive on the street. It's a bitchin' setup.
