How much horsepower did you get with 2 flowmaster 40's?

[Seraphitia102]

I just got my Mustang GT welded in with 2 Flowmaster 40's street muffler. Does anyone know how much flywheel and rear wheel horsepower does 2 Flowmaster 40's mufflers add on the stock H-pipe (if any horsepower at all?)

 

[GT2000JAY]

You won't really pick up anything with weld-in Flows.

1. The stock H pipe is the biggest restriction
2. The pipe diameter on the catback is the same with weld in mufflers.

It will sound faster, though.

Jay

 

[Pitch Black]

Maybe 3rwhp on a good day

 

[XStanger]

Sounds like 15hp, really not enough to even feel.

 

[RysRed96GT]

0.45 hp

 

[Mustang5L5]

0 HP

But it sounds bad-ass

 

[Fast02]

You wont lose any horsepower and will gain street cred.

 

[Mustang5L5]

Yup, any stang with any exhaust sounds bad-ass on the street. Intimidation factor is worth 20-25HP alone!

 

[codyGT]

I think the only time you will really free up any power is with a strait through type muffler. Flowmasters onlt flow slightly better than a stock muffler.

 

[myponyrocks]

I thought flows added a small ammount of torque too? And also even though the HP gains are minimal, they are more consistant through out the whole band?

 

[Seraphitia102]

thanks folks! So in other words, I'm not gettin jack for horsepower, it's practically all show, no go right?

Thanks cool though, at least I sound bad ass

 

[Darkhorse845]

2 or 3 RWHP

 

[crew_dawg16]

i would go with a non-baffled, straight-through muffler like magnaflow has. You can actually look through the muffler and there is less restriction this way. They aren't as loud as flows, but have a more refined sound, especially with an o/r X pipe

 

[Wayne S]

Yup, any stang with any exhaust sounds bad-ass on the street. Intimidation factor is worth 20-25HP alone!

my mufflers are still stock

 

[merc123]

What about flows with an o/r h-pipe?

 

[Seraphitia102]

i got flowmaster 40's clearly for the sound, but if i can get extra horsepower, than that's even better

 

[nhra427]

I think the flows will help with a o/r h pipe. i think all the power loss would be with all those cats and the flows will help when the cats are gone or with hi flow cats

 

[tomustang]

I thought flows added a small ammount of torque too? And also even though the HP gains are minimal, they are more consistant through out the whole band?

.46tq

 

[CManT1914]

I'm gonna jump in and say none also. I got mine in a long time ago and didn't notice ANY difference, except in the sound. When I did my o/r h-pipe though, that's a whole other story. It REALLY helped, I dropped .35 seconds off my 1/4 ET with it. When I did my dumps, no HP gain, but holy CRAP does it sound scary now. I set off car alarms all the time, and scare small children and animals. It's great.

 

[1low03gt]

Almost all cat back exhaust,or weld in mufflers give little to none in hp.If you add an aftermarket h pipie/x pipe,then you will maybe gain a "few" hp out of the mufflers,other then that,they are for pure enjoyment of sound,and intimadation.