silver-bullet

OK, I am getting my new exhaust soon and was wondering which muffler to get. I have the 5.3 w/ a whipple s/c, Jba headers, and other mods. Right now i have a 40 series Flowmaster 3" inlet and dual 2.5" outlets. it doesn't sound to bad but i have heard alot of the guys on here say they don't give you the HP you should get from a high flow muffler or the sound.
I have heard alot about the Magnaflow and corsa mufflers but don't know what to look for when Muffler shopping.
If you could tell me the brand and model that you prefer and why it is better than others that would be great. Thanks

redwagon

magnaflow. they are considered a straight-through muffler.

silver-mod-o

iTrader: (15)

single in, single out 3" magnaflow... they sound VERY nice and you'll see a definite increase over the flow-pooper

silver-bullet

is this it?
http://cgi.ebay.com/ebaymotors/MAGNA...40458089QQrdZ1

I see alot of the guys are running the y pipe also, is this the one to get? I don't know if i need 3" into dual 3". Or 3" into dual 2.5".
http://cgi.ebay.com/ebaymotors/10798...38135293QQrdZ1

Frito Bandito

iTrader: (4)

FYI - https://www.performancetrucks.net/fo...ight=cool+test

I personally think the majority of the Flowmaster haters on this board are simply regurgitating what other people have said. Having said that, aerochambers sound good, as do IMCO mufflers.

99Silverado5.3

iTrader: (7)

Went to the track yesterday and met a guy there w/ a Silverado SS w/ programmer, flowmaster exhaust, UD pulley, and cold air. He was running 14.5 and he said a couple weeks before he had straight pipe in place of the muffler so basically running no muffler and was running 14.3. So even w/ the cooler weather last night he was running .2 slower w/ the only difference being the flowmaster. Me on the other hand was running 15.5X@89 w/ a flowmaster, programmer, no cats, air filter, and full tank. Last night ran 15.08@91 w/ only difference being bullet muffler and in place of the flowmaster and 1/4 tank. So now you know why everyone refers to flowmaster as "slowmaster".

UBLUZIN03

iTrader: (1)

Magnaflow..

jakebdb56

iTrader: (24)

there's a lot of flaws in your theory against the flows being why your truck was slow... Yeah, the flows don't flow as much as some mufflers, but is your exhaust really outputting that much airflow? no... unless you have a turbo setup pushing lots of air through your exhaust. and fyi 3/4 tank is roughly 18 gallons in the average chevy truck. 18 gallons of gasoline = an extra 160 lbs. approximately. cooler weather can also make you run rich, depending on values being read from your PCM. datalogging would really backup the muffler myths, that and good hard accurate dyno numbers.

99Silverado5.3

iTrader: (7)

No theory, just some numbers and info I had about the point someone said about flowmaster haters on this site. It's no myth that the flowmaster is one of the worst flowing mufflers made.

Frito Bandito

iTrader: (4)

Did you look at the link I posted? A blown 5.3 only showed a 6rwhp and 5rwtq gain by going to an open cutout over a Flowmaster. The poster said there was one graph that showed a 9rwhp gain that was lost. Even at a 9hp gain you probably wouldnt see a full tenth faster at the track. Keep in mind the vehicle is an SUV and probably has a catback with the more restrictive 50-series muffler.

The information you posted is interesting but doesnt prove anything. You are talking about runs on different nights under different conditions. Had the runs been back to back on the same night under the same conditions (no other changes, same amount of gas in the tank, etc.) that would mean more to me. I dont deny that straight through mufflers flow better, its just that those flow numbers dont seem to translate to real world gains most of the time. I could sit here and rattle off stories all day about my buddies running open headers/open cutouts instead of their usual Flowmaster duals on their 11 and 12 second Camaros, Firebirds and Mustangs and gaining nothing at the track. I've seen the flow charts that Oxidizer (I think it was him...) posted showing a straight through muffler outlfowing a Flowmaster by something like 200cfm. It's undeniable evidence that Flowmasters dont flow as well as some other mufflers.

I stand by my statement that the vast majority of Flowmaster haters are merely regurgitating what they have heard/read from others. I have a Flowmaster muscle truck catback on my truck and love it. It's the only affordable catback for our trucks that has a deep, agressive sound. It looks great with the tips exiting in front of the passenger tire, too. I dont really have a vester interest in this subject, I just have a Flowmaster because I like the way it sounds.

I'm not particularly loyal to Flowmaster, I'll be getting Pacesetters soon and I will most likely ditch the Flowmaster for 2.5" duals with Aerochambers and turn downs.

That's just my 3 cents (I do tend to ramble on).