Just installed Mufflex 4inch
Just installed Mufflex 4inch I originally had a TSP y and GMMG catback on my car and loved it. After the addition of a rather rowdy cam shaft, I could not handle the rasp and drone any longer. I also felt like the reduction in the y pipe was holding me back as well. I liked the idea of true duals but did not want them to be dumped and couldn't find a decent shop to run them over the axle. I found a used mufflex system with a cut out and custom 3in to 4in y pipe locally for a great price and snatched it up. The result is night and day difference. Zero drone or rasp and a much deeper and better sounding tone. It has a flow master muffler as well. I would really like to get back on a dyno and see how much power I picked up. Any guesses? Attachment 510423
I bet you lost power. The flow master muffler they use is horrible. I had the spintech muffler on mine when it was a 404". It made 474 through the muffler. Added a cut out and it made 497 with it open. Get a 4" cut out or maybe replace the muffler with a Borla XR1, like I did.
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I had my true duels done with a crush bender over axle. Not easy job, if my friend wasn't the one who did it he said he wouldn't have done it otherwise. No drone, no rasp, no loss in power (only bolt ons) paid less than a Texas speed Y pipe for it. What state are you in
Just installed Mufflex 4inch
Originally Posted by blk00ss
I bet you lost power. The flow master muffler they use is horrible. I had the spintech muffler on mine when it was a 404". It made 474 through the muffler. Added a cut out and it made 497 with it open. Get a 4" cut out or maybe replace the muffler with a Borla XR1, like I did.
Just installed Mufflex 4inch
Originally Posted by Mappinsj
I had my true duels done with a crush bender over axle. Not easy job, if my friend wasn't the one who did it he said he wouldn't have done it otherwise. No drone, no rasp, no loss in power (only bolt ons) paid less than a Texas speed Y pipe for it. What state are you in
I don't see how the flowmaster could be better than the spintech. It's a chambered muffler just like the spintech. Any of the straight through race mufflers will be good.
Unless you have a really big engine, going to 4 inch won't garner you any gains over the GMMG. A Flowmaster or Spintech muffler would have slightly more restriction vs. the GMMG chambered exhaust.
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Verdad Gallardo Just installed Mufflex 4inch
Originally Posted by Paul Bell
Unless you have a really big engine, going to 4 inch won't garner you any gains over the GMMG. A Flowmaster or Spintech muffler would have slightly more restriction vs. the GMMG chambered exhaust.
Depends on the setup. It doesn't take as much as you would think for a 3" single to start becoming a restriction. Hence why so many cars are gaining power with a cutout.
3" y to 3.5"-4" single without a cutout is lighter but still increases the flow
3" y to 3.5"-4" single without a cutout is lighter but still increases the flow
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From: Leander TX
local buddy with a heads ms4 cammed 99 trans am that had 1 3/4 SLP headers slp y and an a loudmouth1 made 425 on that setup. Ripped it all out went with TSP 1 7/8 longtubes, custom 3" mandrel y pipe and a flowmaster merge into a 4" catback with no muffler and the after dyno lost 4ftlbs of torque but horsepower was 458 after.
Most engines need the exhaust flow speed in the pipes to be high to produce scavenging. Larger piping tends to slow the exhaust flow reducing scavenging. This is not always the case but most of the time it is.
I'm a fan of cutouts. I have a manual cut-out. I don't mind crawling under and capping it.
I have a garage built 3 inch catback with a hooker maxflow muffler. When I open the cut-out it picks up 14hp and 18 lbtq all over. For $25.00 and a little sweat, its a heck of a deal.
I have a garage built 3 inch catback with a hooker maxflow muffler. When I open the cut-out it picks up 14hp and 18 lbtq all over. For $25.00 and a little sweat, its a heck of a deal.
