Flowmasters.....how bad?

[1Fine69]

I have heard from multiple places about how bad the flowmasters flow and how much they decrease hp. Im thinking about just changing out my mufflers but i dont know what to go to. I have 1 3/4 inch headers and and the pipes are 2.5 all the way. What mufflers should i go with to get the best flow, horse, and sound?

[andrewb70]

Dynomax Ultra-Welded

[rocketman]

i don't know how a flowmaster hurt's flow.there the best hp muffler out there,i have seen engine where they actuall MADE horsepower.i would leave them

[CAMAROBOY69]

I also havent heard where flowmaster reduce flow. Mabey I didnt get the memo but I have always thought highly of them. One of the only few mufflers that I think you can literally run over with a car and it wont even dent.

[1Fine69]

yea trust me i know....when i lowered the car i had to chop the inlets and outlets 1/8 and also the pipes......it took hours haha. its wierd people on ls1tech and other various sites call them "slowmasters". i dont know how i get such different varrying opinions

[1Fine69]

i just realized what the problem is. cross chambered flowmasters suck. I got single in single out. everybody says those are great

[zbugger]

Yeah, the crossflow style is good for ground clearance, but not the best for performance. At least that's what I've noticed. It also depends on engine variables as to whether you'll lose performance of not. They don't flow the "best" of all the mufflers, but for what they are, they can increase your performance.

[rocketman]

the crossflows on a camaro are good for bolt on,but not much past that.NO crossflow is that great with alot of horsepower.

[rocketman]

my 37 coupe run run 7's threw flowmasters must not flow to bad.

[speedster]

Not being a pain, but you don't build a company that successful with products that suck.

[1Fine69]

you may runs faster than what you re running. seeing the dyno sheets of cars gaining hp when getting rid of their flowmasters made me nervous. i just had to look into it more and realize that there are different mufflers for different applications. My application would be getting as much flow and hp as possible. Some people already have enough!

[Steve68]

4th gen Ls1 cars, there are better mufflers, reg cars like ours there fine

[gearbanger]

There was a guy over on another forum that put out a CD of exhaust system sounds on a pontiac 455. He mocked up each system in the floor and ran it at different RPMs and reved it a few times so you could hear each system. He tried probably 30-40 different sets of mufflers. He also tried each set of mufflers with and without an X-crossover. He also flow tested each muffler to test the resistance. The flowmasters didn't so to well on the flow test. The dynomax super turbos actually flowed better than a straight piece of pipe and the dynomax ultraflow welded were right up near the top as well. If you are interested in the CD, Tom Hand is the guy and he hangs out over on the Performance years forum occasionally.

[baz67]

Not being a pain, but you don't build a company that successful with products that suck.

Yes you can. Just look at Ford.:jump:

[1Fine69]

that cd sounds great. the videos on ls1tech are great to listen to. i just dont feel like taking more stuff apart.....i feel like f'n getting my car on the road! i hate school

[speedster]

Yes you can. Just look at Ford.:jump:


:lmao:

[bobbaganoosh]

Turbo cars can lose power with a chambered muffler, but with n/a cars the hp difference between different performance mufflers isn't a whole lot.

[Drewhelm]

The guy who did the testing was Jim Hand. Flowmasters did not flow very well at all. For this reason I am replacing mine with a set of Goerhlich Xlerators. :)

Drew

[Drewhelm]

Here's the new sound....

http://video.google.com/videoplay?docid=-1827055939939894487

[rocketman]

Every exhaust company say's there's better,I was at Des Moines Goodguys on Saturday and Dynomax had there trailer with differnet mufflers and there mufflers by having a vacumn suck air threw the mufflers to show how bad everyone else is.Whats it prove nothing.


One car make react differnetly with differnet mufflers,Turbo and blower engines don't need alot of muffler to make horsepower or torque,as where a n/a or nitrous motor make love a muffler for backpresure.

So just because on guy's combo did better with another muffler doesn't mean everybody needs to run out and change mufflers.

[nitrorocket]

I changed my Flowmaster 3" 50 series Delta flow's out to Dynomax 3" ultraflow welded, I pick up huge power. I would guess Dang near 100 hp! Also droped my AFR to the lean side by almost 1 point. That just shows right there how restrictive they are!

I think for a car without much power that you will not notice much of a difference. The more power you make the more difference you will see.

The car now has a deeper more quiet tone. The Flowmasters had a higher pitch hollow tone. I like the now quieter sound.

[zbugger]

Nitro, the mufflers work uner different principles. Chambered mufflers usually work on a scavenging principle. Turbo motors, last time I heard, don't really use scavenging. Therfore, a straight through style muffler will work better for your application. There have been people with N/A motors pick up upwards of 40-50 hp by swapping to Flowmasters. It all depends on the motor, how it's designed, and whether or not it's forced induction.

[Bill Howell]

I honestly do not know how much hp I gained/lost when I installed the flowmasters on the goat, but, like all my other cars, I love the way the exhaust sounded. I have used flowmasters for years, and always been happy. Maybe it is because of the blower, but I like the way the tone turned out on the goat.

[69ratfed]

I like my Spintech Sportsman XL's

[CHILI442]

If Flowmasters are so great, let me ask you a question. What mufflers did the top competitors use in the Popular HotRodding Engine Masters Challenge? The top three competitors the first year all used Magnaflow. The top two competitors the second year used Magnaflow, and the third place competitor used (I believe) Hooker Aero Chambers. After that PHR made Magnaflows the standard for the competition. Anyway, I don't claim to know everything, but when Joe Sherman and John Kasse use a product with such a high level of success I tend to take notice. If the almighty Blowmaster is such a great muffler then why weren't these guys using them. In my opinion, you can keep those coffee cans. I'll never run a set.

[go-fish]

Go Old School!!! Glass Packs, baby !!!
Really though, There is a little too much emphasis on finding the "KIng of Mufflers" As stated above, different applications respond better to different mufflers. I wouldn't ever build an engine that was exactly like an Engine Masters engine for the street, I would look at each individual component and evaluate whether it would work with my combo. I would do that right down to the muffler. I've seen vacuum pumps on those engines, I'm not going to put a vacuum pump on mine because they use'em.

[1Fine69]

im torn between the new super 40's that flow slightly better than my original 40's but sound deeper and the delta force race 40's single chamber. i dont think the super 40's have that old school tone i like so im leaning towards the delta forces. the delta force 40's do come in a 2 chamber as well though. will the 1 chamber be to loud? i mean i have the originaly 40's now which everyone says is loud but i dont think they are bad at all. everyone says how the 1 chambered flows are much better than the two so i dont see anything wrong with the 1 chamber delta force 40's. what do u guys think?

[NOVA]

I changed my Flowmaster 3" 50 series Delta flow's out to Dynomax 3" ultraflow welded, I pick up huge power. I would guess Dang near 100 hp! Also droped my AFR to the lean side by almost 1 point. That just shows right there how restrictive they are!

I think for a car without much power that you will not notice much of a difference. The more power you make the more difference you will see.

The car now has a deeper more quiet tone. The Flowmasters had a higher pitch hollow tone. I like the now quieter sound.

I am doing this exact same switch next week on NOVA, I am tired of the sound of the flowmasters, and after reading this post sounds like I coud get a bonus with added H.P? that would be sweet!

[LS6 Tommy]

Although I know there's much more to muffler design than just flat-out CFM capability, most other mufflers out flow Flowmasters. I won't say that Flowmasters "suck", but I do know every single exhaust system shootoot I have ever read or seen live has proved that they are not as good as Dynomax Ultraflows, Borlas or most of the other similar designs. Forget about the fact that they cost more, rust out in a year, the baffles break loose and they weigh a ton. I also don't particularly like the way they sound, but that's a personal preference issue.

Tommy

[vcho455]

Exhaust systems are a exercise in compromise. How much noise can you live with to get the power you want. I've seen a low 10 second 55 corvette make a pass with less noise than most taxi cabs. Did he give up power? Of course. Was he happy with the trade off? Yes. Was it easy for him to get there? No. Most people can be satisfied with a stock system. But for the rest of us we will have to experiment with different systems. If your picky about your sound, be prepared to buy several complete systems for your car. If your looking to have every pound/foot of power you can get. Get yourself to a chassis dyno or to the track with a data acquisition system. Be prepared to buy several complete systems. You may have to mix and match stuff. You should be prepared to change the system with every substantial change to your power plant. The good thing is that is easy to sell used mufflers your not satisfied with. This is the only way to satifaction.

The information that Jim Hand has is available in his book on HOW TO BUILD MAX PERFORMANCE PONTIAC V-8'S. The information on mufflers is without equal. (Although some of the part numbers listed are no longer available.) But beware that his car has to live with in certain rules to be legal for the stock classes he runs in. Flow numbers are also not the end all for exhaust performance in every situation. Buying a welder and learning to do it yourself, will pay for itself. Plus, no one else will get your system tucked up out of the way for the best ground clearance the way you will.

[93HULK]

I like turbo mufflers. Especialy 76mm or bigger thats where I found the most HP.J/K :smoke:

[Norwoodx55]

I like turbo mufflers. Especialy 76mm or bigger thats where I found the most HP.J/K :smoke:
Too bad those are so damn expensive or I would have a pair of 'em too!