How Well do Stock Mufflers Flow?? Look here an see.

2k05gt

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Here are a pair of my Time Slips from Last weekend, I wanted to see if the Stock Mufflers
were too restrictive or not so I made several runs with the Stock Mufflers and several without mufflers. I found 2 times that were almost identicle to compare.


mufflertest-1.jpg

Now Notice these side by side, no real difference..
mufflertest.jpg


Conclusion is that even with JBA Headers, JBA High Flow Cats the Stock Mufflers flow with little restriction..
 

Bingo

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The only reason to get rid of stock mufflers is because of: a) sound and/or b) weight savings.

I think it's impossible to test "flow" without actually putting them on a flow bench. Any differences at the track or on the dyno probably fall within the degree of error, so even if there is a difference, you can't be sure.
 

Stangtuner

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I never thought the stock mufflers were much of a flow restriction. More just them being packed with more sound deadening. The real restriction is in the headers and stock cats, and you have already addressed that issue I see.


btw do you have a sound clip of your car. I want to do longtubes and catted H into the stock mufflers. Just have'nt heard one on the street yet. Thanks !
 

don_w

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I could be wrong, but I think Adam's black car had a bone stock exhaust system when it went into the 9's, too.
 

stkjock

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Guess Ford did a good job with the exhaust!
 

Bingo

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Hahahaha, i swaped for some corsa and they weight at least twice than the stock one.
:shock:

Well, if you're worried about weight that much, you run Loudmouths or Stingers. :clap:

I know the Bassani Race muffs I had on were about half the weight of the stockers.
 

Pumpkinfish

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Hahahaha, i swaped for some corsa and they weight at least twice than the stock one.

The price one pays for a good sound without drone. I have removed the Corsa's many times but always end up with them back on. I just can't live with drone:shock:
 

RedStang06

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I never bought into the claims by manufacturers that their mufflers would add measurable power gains, like 5-15 hp.

It's about sound and style.
 

memphis90

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The stock mufflers are a straight through design. Not much restriction there.
 

Born To Run

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Mufflers

I just did a test on the dyno on Thursday night.
I have QTP exhaust cut offs,i did a pull with them closed then with them open.The dyno used was a Mustang dyno.
Results were 5 RWHP & 5RWTQ gain with cut-offs open,my car is supercharged.The cut offs are located downstream of the cats,my exhusat manifolds are stock as is the rest of my exhaust system.
Anyway there you go,more free info.
I use the cut offs to hear my car when racing cars with open headers in the mod class.
 

ixtlan

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When the S197 came out Magnaflow tested the Ford muffs to see how they could improve on them.
They decided they could only improve the sound.
In fact the whole system was done very well from Ford.
The Ford Manifolds, and exhaust system was redone for the S197 and they did a very good job.

Add F/I and things change, but for N/A the system is GTG.
 

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