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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

no throaty sound with new 40 series flows

  • Thread starter Thread starter leveling
  • Start date Start date Oct 12, 2005
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leveling

New Member
Oct 12, 2005
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Oct 12, 2005
#1
  • Oct 12, 2005
  • #1
I just installed 40 series flowmasters on my 89 mustang gt conv. and it sounds like my stock mufflers did. All the posting about the 40 series mufflers talk about how great the sound is. I am getting a very stock sound and do not know why. What gives?
 

will1992

Member
Aug 25, 2005
123
0
16
Oct 12, 2005
#2
  • Oct 12, 2005
  • #2
i also have them on my 92 vert gt, make sur theyre not delta flows by looking at the serial number on the outlet side of the case- 2 1/4 inch outlet =42443 2 1/2 inch outlet= 42543 these serial numbers are from the originals, if the ones you have have a 9 in front of these serial numbers they are delta flows
 

cevtv

Founding Member
Sep 15, 2002
1,113
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37
Massachusetts
Oct 12, 2005
#3
  • Oct 12, 2005
  • #3
leveling said:
I just installed 40 series flowmasters on my 89 mustang gt conv. and it sounds like my stock mufflers did. All the posting about the 40 series mufflers talk about how great the sound is. I am getting a very stock sound and do not know why. What gives?
Click to expand...


Are you still running the factory cats/H-pipe???




.
 

Dean85GT

New Member
Nov 27, 2004
502
1
0
Thorold, Ontario, Canada
Oct 12, 2005
#4
  • Oct 12, 2005
  • #4
They WILL get louder. Mine got louder after about a couple weeks.
 

gungfusemaj

Member
Dec 13, 2003
211
0
16
Bradenton Fl
Oct 12, 2005
#5
  • Oct 12, 2005
  • #5
It takes a month or 2 depending on how much you use your pony...the heat makes "changes" to the medal over time...
 

Darkwriter77

Resident Ranting Negative Nancy
5 Year Member
Jul 1, 2005
314
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134
Apache Junction, AZ
Oct 12, 2005
#6
  • Oct 12, 2005
  • #6
The metal changes? How? Changes shape? If it's so weak that the baffles, themselves, change shape from heat and pressure, that's some seriously wimpy steel they're using in their products. If Flowmasters had any sort of packing/insulating material in there, then I could see there being a break-in period, a-la Dynomax UltraFlows and Hooker Maximum Flows (they sounded TOO quiet on mine for the first month or so before the sound packing settled in, then they got wicked under WOT). But unless Flowmaster's changed their designs yet again, they're just a bunch of holes and triangle deltas of solid metal welded into them - nothing at all to "break in."

I'd say whatever it sounds like now is what it's gonna sound like for good ... until they rust out.

(On a totally unrelated note, the animated silhouette of this iPod Nano chick next to the Quick Reply box is making me crack up. Looks like she's fanning away a fart... )
 
S

strokedandblown

Banned
May 3, 2005
555
0
0
USA
Oct 12, 2005
#7
  • Oct 12, 2005
  • #7
ehh mine go louder as well over time i enjoy the deepness of them, but i have lt's, and an X pipe w/no cats. it sounds like your still on your stock H
 
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IntenseBlue

Member
Jul 10, 2005
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Oct 12, 2005
#8
  • Oct 12, 2005
  • #8
I've got MACs and it took 3 weeks for them to sound the way they do after 2 months.
 
E

emagdnim

Active Member
Feb 5, 2003
391
15
28
Oct 12, 2005
#9
  • Oct 12, 2005
  • #9
I dont understand how they can break in either since its just metal with holes in it... but apparently alot of people say it happens i just dont understand how its possible.
 

TrophyHead

15 Year Member
Mar 18, 2003
1,195
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49
PA
Oct 12, 2005
#10
  • Oct 12, 2005
  • #10
leveling said:
I just installed 40 series flowmasters on my 89 mustang gt conv. and it sounds like my stock mufflers did. All the posting about the 40 series mufflers talk about how great the sound is. I am getting a very stock sound and do not know why. What gives?
Click to expand...

It's all about the off-road H-pipes.
 

srothfuss

Last night I stabbed the same guy 7 times in a row
Oct 17, 2004
1,796
3
0
Woodward Ave.
Oct 12, 2005
#11
  • Oct 12, 2005
  • #11
With a catted X-pipe or H-pipe your car will be quiter than one that isn't running catalist's. My car is very loud with an O/R H-pipe and some 40 series flows.
 
8

89white50

Member
Nov 16, 2004
440
1
18
central MA
Oct 12, 2005
#12
  • Oct 12, 2005
  • #12
It's all about the off-road H-pipes.
Click to expand...

sounds mean as hell
 

gt40_2003wes

I did sound a wee bit gay there.
Aug 14, 2005
461
2
48
ky
Oct 12, 2005
#13
  • Oct 12, 2005
  • #13
mine is just now startin to get louder had them bout 3 weeks now and the more i drive the more i love the sound.
 

Shakerhood

20+ Year Stangneter
Oct 28, 2004
3,356
208
114
Ohio
Oct 13, 2005
#14
  • Oct 13, 2005
  • #14
I put my Flows on in 2000 and the sound has not changed at ALL, there is nothing but Chambers inside of flowmasters, there is no packing to burn out of them! I kinda think you Guys are hearing what you think you want to hear!
 

Paul Perreca

New Member
Mar 30, 2005
1,085
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0
Oct 13, 2005
#15
  • Oct 13, 2005
  • #15
Darkwriter77 said:
The metal changes? How? Changes shape? If it's so weak that the baffles, themselves, change shape from heat and pressure, that's some seriously wimpy steel they're using in their products. If Flowmasters had any sort of packing/insulating material in there, then I could see there being a break-in period, a-la Dynomax UltraFlows and Hooker Maximum Flows (they sounded TOO quiet on mine for the first month or so before the sound packing settled in, then they got wicked under WOT). But unless Flowmaster's changed their designs yet again, they're just a bunch of holes and triangle deltas of solid metal welded into them - nothing at all to "break in."

I'd say whatever it sounds like now is what it's gonna sound like for good ... until they rust out.

(On a totally unrelated note, the animated silhouette of this iPod Nano chick next to the Quick Reply box is making me crack up. Looks like she's fanning away a fart... )
Click to expand...

I'm pretty sure, ALL muffler grow louder with miles... It's not that its cheap metal or what not, it's that they break in, they get used to the way the exhaust flows through them, all metal expands and contracts due to heat and cold conditions, when they expand and contract so many times, they change shape, and they change sound considerably, it's awesome... my prostreets are gonna prob be really mean from the start, can't wait till they break in lol
 

rd

Founding Member
Jan 12, 2000
3,316
63
109
Ocean Springs MS
Oct 13, 2005
#16
  • Oct 13, 2005
  • #16
I had the same feeling about the Super 40's I just put on my 82, they seemed quieter than the Thrush Turbos I took off.

But they do have a deeper note. I have no tailpipes, and they dump a couple feet in front of the axle, so that my affect it also.
 

darthcual

Member
Mar 31, 2005
985
19
18
Arlington, TX
Oct 13, 2005
#17
  • Oct 13, 2005
  • #17
Its all about the total package. Headers with an off road x or h along with those flows will make a difference BIG time.
 

Darkwriter77

Resident Ranting Negative Nancy
5 Year Member
Jul 1, 2005
314
281
134
Apache Junction, AZ
Oct 13, 2005
#18
  • Oct 13, 2005
  • #18
I dunno. The physics and such of it just don't make sense. The baffles would have to physically change shape for them to "break in," and I just don't see that being a realistic possibility - those delta shapes are welded top and bottom to the casing, so there's really nowhere for them to flex/bend.

Only theories I have to explain a sound change on Flows:
- Computer re-learning the air/fuel mix and such, but only if you disconnect the battery at the same time as the exhaust change;
- Minor exhaust leaks at the flanges develop as the connections settle into place over bumps, turns, and heat cycles;
- The existence of that obnoxious Flowmaster drone at most RPM's becomes more and more impossible to deny after the initial "newness" of the exhaust wears off, and one is faced with a subconcious decision to either love it or hate it.

Either way, I figure the side-exit Flows will be louder than the average cat-back setup, but again, you'll have clearance problems and you might be bothered by the fumes wafting up to through the windows at stoplights. (On mine, I found it quite enjoyable. Carbon monoxide and vehicle emissions make for a groooooovy high... )
 

Mavrick

Founding Member
Aug 29, 2002
2,264
0
46
Collingwood, ON
Oct 13, 2005
#19
  • Oct 13, 2005
  • #19
My car with 1.5" longtubes, stock modified offroad H, and delta flows with tailpipes is very loud, and i love it. I hope it doesn't quiet down too much when i put cats on it.
 

Look Its Aaron

Your car looks like it came straight from Mexico.
Founding Member
Nov 18, 2001
2,634
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48
Fontana, Cali
Oct 13, 2005
#20
  • Oct 13, 2005
  • #20
To the original poster.

Are you still running the stock mid pipe with cats?
 
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