muffler flow chart

http://www.broaderperformance.com/muffler_flow_tests.htm

Now the question is how much cfm difference will make u gain a horse or looze it
And how much backpressure is needed for a na motor

as u can see a cherry bomb straight thru muffler has the same flow as a 2chamber flowmaster so i dont know who on this forum thinks flowmaster doesnt flow. Borla and dyno max flow the best and are not as loud as a cherry or flowmaster but cost more. So if your looking for a muffler it is true that the more you spend the quieter and better flowing muffler you will get.

hooker aero chamber 75$
2chmber flowmaster 70$
dynomax superturbo 60$
AND THE BEST FLOW MUFFLER borla turbo
Cheapest one i found depending on size is 107$

Although flow doesnt have a great effect on horsepower on a 140hp 4.0l
But if you have a v8 or 4.0l stroker it would make a noticeable diff on the dyno

http://www.youtube.com/watch?v=jFuT5fpzVTc

I wish someone would do this test on a 4.0l like this one done on a sb miata and end all this muffler debate

um sure someone has a smartass comment for something i said or has an opinion on the matter

I'd like to see a muffler test where someone measures decibels on the same vehicle and swaps some mufflers. It would be nice to compare the sound levels versus flow from the chart you posted the link to.

FWIW I have a Borla and think it's too noisy on the highway. It's fine at low RPM, but 2700rpm on the highway is annoying.

I wouldn't spend money on a Borla product for my DD, no matter the performance gain.

Some idiot put a Borla cat back system on my 633 before I bought it. Loud and droning, how exciting! Buddy of mine put one on his truck(Ford) same result.

tbburg said:

I wouldn't spend money on a Borla product for my DD, no matter the performance gain.

Some idiot put a Borla cat back system on my 633 before I bought it. Loud and droning, how exciting! Buddy of mine put one on his truck(Ford) same result.

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I needed a new header since I had the standard crack in the original and I think the Borla header is the nicest one out there for the 4.0. Nice thick flange, 304 stainless instead of the 400 series most manufacturers use, band clamped mandrel bend head tube instead of a flange, etc.

So I figured I would get the rest of the system while I was redoing the header and cat. Mistake. The header is excellent, fits very nicely, no problem with having to grind on it or the intake manifold to make it fit like some folks have had to do with other headers.

I'm glad I sprung the extra coin for the header, but the muffler and cat back sucks. Drones at highway speeds and the end of the tail pipe made this weird bend that doesn't fit with longer shackles.

I would really like to find a quieter, at least less droning at highway speeds, muffler. I'm even considering going back to a stock muffler.

Flowmasters have gone up in price. I guess they must be very proud of their products. Yes they have a very distinctive sound and if that's what you are looking for great. But,.... When my Flowmaster popped a leak in the seam I replaced it with a Magnaflow from Kolak that has the same stainless steel construction, is quieter and cost significantly less.

Yeah, edit your original post instead of posting 6 times in one thread.

what I have to say - the first time I looked at this thread I was wondering wtf you were on, because you looked like you were arguing with yourself.

It's exhaust, I stick with OEM... 50 bucks for a new muffler shipped from rockauto and no inspection worries. I don't particularly care about it.

They didn't do a test on a Flowmaster 50-series (3-chamber) with 2.5" IN/OUT (that's what I have).

They also didn't do a Dynomax Ultraflow of any size.

projectTK said:

um sure someone has a smartass comment for something i said or has an opinion on the matter

Click to expand...

As little backpressure as possible is best for any motor. Enter the velocity/backpressure argument.

projectTK said:

um sure someone has a smartass comment for something i said or has an opinion on the matter

Click to expand...

bigalpha said:

Yeah, edit your original post instead of posting 6 times in one thread.

Click to expand...

If he did that, it wouldn't bring his thread back to the top and he would have less opportunity to be a Flowmaster fanboy.