Do flowmasters really suck lots of HP
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Teching In
Joined: Apr 2009
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From: Minnesota
Do flowmasters really suck lots of HP I want to get a new exhaust system for my car and currently have Hooker LT and cats and a Flowmaster cat back. The car dynoed out at 440 rwhp and when i opened the cut out in gained like 18 hp. I want to get away from the cut out and the cats. Was thinking of going with the Magnaflow set up but dont know if that will help or not. Like to keep it as stock looking as possible. Any input would be appreciated.
There is a reason Flowmaster has so many bad nicknames...slowmaster...chokemaster...
You have a cutout though so if you like the sound why not keep it? If you don't like the sound then of course get rid of it.
You have a cutout though so if you like the sound why not keep it? If you don't like the sound then of course get rid of it.
I want to get a new exhaust system for my car and currently have Hooker LT and cats and a Flowmaster cat back. The car dynoed out at 440 rwhp and when i opened the cut out in gained like 18 hp. I want to get away from the cut out and the cats. Was thinking of going with the Magnaflow set up but dont know if that will help or not. Like to keep it as stock looking as possible. Any input would be appreciated.
I've PERSONALLY watched a car pick up 10 horses and 8 ft-lbs from simply cutting off the flowmaster and putting straight pipe on the car. Sounded like crap but gained power. As stated if you like the sound and have a cut out, you have the best of both worlds for you.
gained 30rwhp UNTUNED popping open my cutout at only 4500 rpms before having to cut the run short. Would be closer to 40-50 rwhp tuned based on how lean it was running and rpms.
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Thread Starter
Teching In
Joined: Apr 2009
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From: Minnesota
If you like the sound of the flowmaster then get a mufflex 3 1/2 or 4" single system. It uses a single pipe over the axle through a big flwmaster and a single pipe out that dumps. It's mostly hidden on a camaro set up. It's the crossflow style mufflers that kill the power.
Launching!
Joined: Apr 2006
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From: Back to Newport News
What kind of exhaust setup do u have? I have Pacesetter LT's w/ their ORY and a 3" E-cutout. At low rpm's with the cutout open it sounded like ***. Then I got the Flowmaster merge welded in my ORY and it now sounds 10X better. No bullshit. I know yall are probably sick of everyone raving about the FM merge and all the hype about it, but it is DEFINATELY worth it as I cannot stress it enough to people. Trust me, I was skeptical at first before I ordered the merge, but I'm glad I did. It really made the cutout more "enjoyable" sounding when just puttin around town. Hope this helps.
Yes Hooker is very quiet stock but on H/C car it is loud. I get looks at stoplights idleing and it screams WOT
Magnaflow is only slightly quieter. Horsepower makes noise in these cars ... it is that simple
Especially in our case where everything goes through one muffler unless you do a custom setup. 
i am asking because i know there is a lot of guys that have this and wanted to know what their results were
No I haven't had dual single chambers specifically, although I do currently have duals with a set of no-name chambered mufflers and they're a huge restriction. But I've seen far too many cars pick up more power when they got rid of their slowmasters. Also if I'm not mistaken, when the S-197 Mustangs first came out there were GT's that were LOSING horsepower over stock when they put the slowmaster catbacks on. After seeing all of these results I wouldn't even take one of their mufflers for free.