Flowmasters came with my car when i bought it. After a few minor bolt ons i went to a dyno. There was about a 5-9hp difference with cutout open and closed. Flowmaster sounds pretty good IMO, but thats just it. I am now running SLP LM and love it, a little raspy but ehh...guess ya get it with good flow.

 

my .02

on my old 500rwhp turbocharged 5 liter i picked up 25rwhp going from dual 2 1/2" 2 chambers to dual 2 1/2" dynomax deltaflows. but....

that was on a turbo car. turbo cars run off of a different exhaust principle then every other form of internal combustion engine. turbos have blended exhaust, every other setup is pulsed.

being that everything else is pulsed, actual flow numbers dont mean the same thing they do on something like a cylinder head.

not only that, but the further back the muffler, the less difference it makes. FWIW, i have a flowmaster catback on my LT1. when i replaced the muffler with a dynomax ultraflow my car made no more power and ran no more mph at the track. this is a stock motored car. i think the restriction of a single exhaust does more to restrict these cars then a chambered muffler does.

i have seen 580rwhp out of a set of dual 2 1/2" 2 chambers. so i dont think it really makes a **** what muffler a person runs as long as they like what they have.

 

I have a 3 1/2" (i think) flowmaster system. I cut it off right before the muffler. I didnt notice any difference in loss of torque but i did notice big gains in top end. It pulls much harder now.

*side note* after the throttle body bypass and 160 degree thermostat install and radiator flush i can burn out through all of 1st gear and some of 2nd (A4, 273's, Daytona Dayton 245ZR's). Major increase over the 'chirp' before.

 

I have Flowmaster Single Chamber's and they sound absolutely badass, and have yet for anyone to prove to me that they actually took away power from my car. Either way, I plan on getting a cutout anyways.

 

for the price it would cost to buy a more expensive catback than flowmaster, you could invest the money you saved from buying a flowmaster and put it towards some other boltons that would easily give you more HP than you would have by buying a more expensive "better flowing" catback...

 

I like Flowmaster I think it sounds good its all in what you like.

 

Wow. The Hooker max flow flows the same as an open pipe the same diameter. That has got to be loud.

I have a Flowdaddy. I never thought they sucked but it seems some people have to spend gobs of money to feel better about the products they buy. I had over 300 at the wheels running through a Flowmaster exhaust. That is only rrs, CSI pump, 1 3/4" SLPs and a Moroso CAI. You can't convince me they suck at blowing. Not with my setup at least.

 

regardless to what people say flowmaster sounds good. if it were me id just get a cutout n call it a day. i have seen one or 2 posts on here where people put borla on and got on the dyno and didnt have any gains. so its all in what you want

 

I had the Hooker Maxflow on an older camaro with longtubes, no cats and dumps. THey actually sounded pretty tame while driving normal. They came alive when you put the pedal down but not obnoxious. I wish they made them for our cars. I'm just ordered a Magnaflow catback for the new car. Hope I like it. One person said Magnaflow sounded like glasspacks. I hope they were wrong. Has anyone hear Magnaflow without cats on stock manifolds?

 

I love the sound of my Flowmaster with a 3" pipe and a gutted cat.

 

I like my magnaflow sound! One thing that sold me on the magnaflow over the flowmaster was that its all stainless and comes with some real nice tips out the back.
Also the magnaflow muffler redirects most of the exhaust air right back out the passenger side pipe! So i figured that I might as well spend a few extra $$ and go with a stainless system that I know isn't going to be restrictive.

If you have a flowmaster already and arent making huge amounts of HP i'd just stick with the flowmaster if it sounds good.

 

Man this topic has already been exhausted.

Check the tech link in my sig...Flowmaster = junk = general consensus

You can get a Magnaflow for $280 shipped form performance-curve.com

 

Keep the Flowmaster until it needs replacement. Then go with another brand if you like.


http://www.pontiacstreetperformance....p/exhaust.html

FYI

 

Price has gone up. Just ordered on yesterday. It's $310. shipped now. From performance-curve

 

Just get a cutout.