Muffler replacement recommendation needed


Specracer

GT Owner
Mark IV Lifetime
Nov 28, 2005
7,154
MA
I have Hefner, w cats, went to that after borla. Borla wasn't loud enough. The Hefner works for me.
 

jcthorne

GT Owner
Aug 30, 2011
792
Houston
I have had a Hefner and now an Accufab. The Heffner tips do look nicer but I think the Accufab X sounds better. My Accufab is jethot coated in black and looks pretty good out the back. Now with FMS exhaust the sound is even better.

At 75 on the freeway in 6th I have no noise that I consider a drone (have had exhaust on a Mustang that droned badly) and no difficulty with conversation or listening to the fine stereo while cruising. It does get loud when using the right pedal though. I love it.
 

RaceDeck

*Supporting Vendor & GT Owner*
Supporting Vendor
Aug 11, 2005
289
SLC Utah
Gentlemen,

Everybody has their own standards here and I personally own 5 different exhaust systems for my Ford GT and I've driven and/or ridden in a GT with just about everything available. I currently have a Heffner H-Pipe on my GT with turbos and no cats. It has a droan between 1700 and 2200 RPM. EVERY single X-Pipe and H-Pipe exhaust, with or without cats, with or without turbos, will have that droan and it's right where you cruse (70 to 90mph) in 6th gear. EXCEPT for the stock muffler and the Borla (Ford Racing) exhaust you need to be willing to put up with it. I've had owners tell me that THEIR X-Pipe had no droan and they took me for a drive to prove it. At 75mph in 6th gear their GT was droaning like crazy. When I pointed it out they said, "Oh, I didn't consider that a droan". Anyway, I love the sound of my GT at car shows and while driving fun roads so I'm not gonna change it BUT.....I can't have a conversation with Renea while we are cruising at 80mph because the droan drowns her out, especially with my poor hearing. Trust me on this, there is not a single no-muffler system without that damn droan. Not one.

Chip

Chip - When I first installed my x-pipe, your right...it had a slight droan. Then my friends down at Kirkhams ( Tom ) along with someone who was from Ford helping them on the GT'40' copper car put on a racing heat wrap on the pipes and no more droan ( plus it looks great too) . Yes you can hear the exhaust but no droan at cruising speeds and when you opening it up it howls :)
 

DakotaGT

GT Owner
Mark II Lifetime
Dec 9, 2012
1,715
Sioux Falls, South Dakota
I have had a Hefner and now an Accufab. The Heffner tips do look nicer but I think the Accufab X sounds better. My Accufab is jethot coated in black and looks pretty good out the back. Now with FMS exhaust the sound is even better.

At 75 on the freeway in 6th I have no noise that I consider a drone (have had exhaust on a Mustang that droned badly) and no difficulty with conversation or listening to the fine stereo while cruising. It does get loud when using the right pedal though. I love it.

If you like the Heffner tips, but the accufab sound, definitely check out Kendall's x-pipe (Cool Tech)
 

Beach-GT

GT Owner
Mark II Lifetime
May 8, 2006
887
Seminole Florida
Gentlemen,

Everybody has their own standards here and I personally own 5 different exhaust systems for my Ford GT and I've driven and/or ridden in a GT with just about everything available. I currently have a Heffner H-Pipe on my GT with turbos and no cats. It has a droan between 1700 and 2200 RPM. EVERY single X-Pipe and H-Pipe exhaust, with or without cats, with or without turbos, will have that droan and it's right where you cruse (70 to 90mph) in 6th gear. EXCEPT for the stock muffler and the Borla (Ford Racing) exhaust you need to be willing to put up with it. I've had owners tell me that THEIR X-Pipe had no droan and they took me for a drive to prove it. At 75mph in 6th gear their GT was droaning like crazy. When I pointed it out they said, "Oh, I didn't consider that a droan". Anyway, I love the sound of my GT at car shows and while driving fun roads so I'm not gonna change it BUT.....I can't have a conversation with Renea while we are cruising at 80mph because the droan drowns her out, especially with my poor hearing. Trust me on this, there is not a single no-muffler system without that damn droan. Not one.

Chip


I took the stock muffler and welded 3 inch pipes across the inputs to the outputs and installed cutouts. I was expecting butt loud and quiet as my two choices. I was wrong. Wide open the exhaust goes out the tail and the sound seems to go into the muffler. The result is really nice sound and absolutely no drone at any speed. The muffler stays cool as well. I'm going to remove the cutouts and just leave the bypasses in place. The sound is really nice. Not too lound when driving but authoritive if you step on it. It sounds like no other car on the road.
 

HPGT

GT Owner
Jul 31, 2012
82
Little Rock, AR
The stock muffler is so bulky and tight - I can't imagine taking it out and reinstalling it more than once. There is so much more room around an Xpipe
 

RaceDeck

*Supporting Vendor & GT Owner*
Supporting Vendor
Aug 11, 2005
289
SLC Utah
not to mention the heat that builds and stays with that muffler. the X-pipe and spacing the license plate off the grill lets that heat flow out much better.
 

otis

GT Owner
Mark II Lifetime
Nov 13, 2011
349
Stillwater, MN
I agree with Chip on this one. I have the GT guys X pipe with the stock cats on and it does drone. It's not terrible, but it is there. If I drive under 70 MPH it's tolerable, but any speed over that it gets loud. After about an hour I'm tired of listening to it so I keep the car speed down with the revs under 1500 RPMs and I'm good again. I just can't live with the stock quiet sound and love the effect of the pipes singing out the back at full tilt. I was going to ask Rich and Dennis if they would consider adding resonators to an X-pipe to see what the effect on the sound would be. I just added a fabspeed x pipe to my R8 and the sound is amazing. No drone just a bit louder. What do you guys think about this? (Sorry don't mean to hijack your thread and will start another if you think I am)

Rob


R8-V10-Supersport-Exhaust-1.jpg
 

topshot

GT Owner
Feb 6, 2012
280
Metro Detroit, MIchigan
Headers + Accufab no cats........... nice & loud, can't hear the drone as its to loud..... great pops and stuff.....
 

Simon

GT Owner
Mark II Lifetime
Feb 19, 2013
1,265
Houston
What's jet hot? Ceramic coating?

I have had a Hefner and now an Accufab. The Heffner tips do look nicer but I think the Accufab X sounds better. My Accufab is jethot coated in black and looks pretty good out the back. Now with FMS exhaust the sound is even better.

At 75 on the freeway in 6th I have no noise that I consider a drone (have had exhaust on a Mustang that droned badly) and no difficulty with conversation or listening to the fine stereo while cruising. It does get loud when using the right pedal though. I love it.
 

KJRGT

GT Owner
Mark II Lifetime
May 4, 2006
2,840
SoCal
yes
 

debtdrives

GT Owner
Mark II Lifetime
Apr 20, 2007
438
Oakland, Michigan 48363
Yup. Jet hot is a brand of ceramic coating.
 

t32b

Verde
Mark II Lifetime
Jul 21, 2007
432
Bay Area, CA
I had our famous hand model (Shadowman) install an Accufab x-pipe some time back on my 2005. We agreed that for heat reduction (and classic looks) that wrapping them would be wise as well. I wasn't wild about the sedate sound of the OEM muffler but the real goal of the transplant was heat reduction and better airflow in the engine compartment. I never did a before/after temp measurement at spots in the engine area but it just seems like a much better place for the mechanicals to live without that bulk and airflow block out of there.
Anyway, from the moment I hit the highway returning to the Bay Area from Shadowman's shop, there was some modest droning evident in 5th gear at highway speeds - 70-75 mph. Sixth gear is drone free, seemingly at the same RPM (higher speed of course) versus 5th, though that would seem to defy the laws of physics. I too don't like dragging the car at low RPM going up mild inclines on the freeway - though that motor hardly knows that it might be bogging down a bit.
Net net is that though there is a slight drone in 5th gear (only), the combination of stock manifold, cat's and wrapped Accufab x-pipes is a winner. Hardly any drone. Only evident in 5th. A BIT louder than I would have liked but much better - both sonically and (likely) thermally - in the engine compartment. I highly recommend it.
B
 

PeteK

GT Owner
Mark II Lifetime
Apr 18, 2014
2,470
Kalama, Free part of WA State
Yesterday I replaced my stock muffler with the Ford Racing (FRPP) muffler. My observations on the job and the sound:

The job: Not difficult, but fairly time-consuming. I know Rich (GT Guy) can do it in a couple hours, but it took me all day doing it the first time. Just about when I thought I could get it out, something else was in the way and preventing me from getting it out, so I had to disassemble more of the back end. Part of the trick is to take out the rear tranny mount bolt and drop the tranny on a jack 1-2 inches (that's in the shop manual). The hardest part was getting the old muffler out, because it is bulky and it has the studs that bolt through the cat pipe flanges. Putting the FRPP/Borla in was much easier with the additional room around a smaller can, and it uses nuts and bolts, rather than fixed studs that are on the stock muff.

The sound difference inside the cabin: Let me start by saying that I like quiet at highway cruising speeds, so I was a little concerned that the FRPP muff might be more than I wanted. As we all know, the stock OEM muff is pretty quiet. It does not "drone" at all. That's good if you spend considerable time cruising at highway speed, as I do. About the only sounds you hear inside the cabin are wind and tire noise. The FRPP muff definitely has more engine note when you accelerate, but nothing near as loud as the X or H pipes. From inside, I consider it pleasant, and driving under overpasses (with windows open) sounds really good. At highway speed (windows closed), it does have slight engine note in the 1700-2200 or so RPM range, but not noticeable while cruising flat and level. When I go up a hill, I do notice it, but I do not consider it too much.

I will report back on my impressions as I accumulate more driving, especially if I do a fairly long highway trip.
 
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fjpikul

GT Owner
Mark IV Lifetime
Le Mans 2010 Supporter
Jan 4, 2006
11,680
Belleville, IL
You should be pleased. I've got 35K miles on mine. No drone. Still looks nice all around.
 

B. West

GT Owner
Dec 17, 2012
363
Irvine, CA
Great choice. I have had my FRPP muffler almost two years and it really is a pleasant note especially a WOT. As far as removal and installation, I had Hennessy Performance install mine. They did a good job. The only recommendation I have as far as doing anything differently or advising others is to remove the air box first. It really will make it much easier to remove the factory muffler.
 
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PeteK

GT Owner
Mark II Lifetime
Apr 18, 2014
2,470
Kalama, Free part of WA State
I drove the car again today a fair amount, including about 20 miles of freeway driving. in the 70-80 MPH range, on flat roads, there's almost no increase in engine noise compared to stock. Going up hills, there's some primary-frequency engine note, but not at all intrusive or annoying. I like the louder bark when I put my foot into it, especially under overpasses. All-in, I'm pretty satisfied with the swap and wish I had done it sooner.

One note on the weights of components: On my bathroom scale, the stock muff weighed 55.6 lbs, and the FRPP can weighed 34 lbs. That's pretty close to what others have reported. So, it's a 20+lb weight savings.

B.West: You MUST to remove the air box to get out the stock muffler--no way to get the muff out with it still in place.
 

NorthwoodGT

GT Owner
Jun 12, 2009
1,217
Michigan
Pete- perfect choice muffler. I've had mine on the red car for a little over 2 years and like you said, not annoying at all but when you step into it, you know you've changed the pitch and note of the muffler. now all you need to do is change the supercharger to the Whipple. the combo of the muffler and the S/C really wakes these babies up plus a dual blade Accufab and ultimate tune from Rich. he also installed cooler spark plugs. great combo and very streetable without changing out the fuel system. jmo
 

Nafod

GT Owner
Mark IV Lifetime
I've had an early Ford Racing Muffler on the shelve for many years(9+) and never installed it because I had the Cat delete headers and wanted to install the whole setup and they wouldn't pass the NYS annual inspection.
Relocating to AZ, I installed the muffler only just before the Rally. Two day of driving through the mountain's and a day at the track, the exhaust developed a buzz around the 2K mark.
My dealer in Albany was doing the pre Rally service and the exhaust was installed then. He did mention that I would have to check/tighten the exhaust after about 500 mile. So, this buzz I related to something needing tightening in the exhaust. Turns out everything was snug, but the buzz only increased.
So, maybe 6-700 miles , and the muffler seems to develop the dreaded loose internals/buzz.
Like the exhaust and the sound. Hopefully the buzz can be eliminated.
Next step, contacting Borla . Hopefully Pete, yours is the newer version than the one I had.

Bruce
 

Simon

GT Owner
Mark II Lifetime
Feb 19, 2013
1,265
Houston
I've had an early Ford Racing Muffler on the shelve for many years(9+) and never installed it because I had the Cat delete headers and wanted to install the whole setup and they wouldn't pass the NYS annual inspection.
Relocating to AZ, I installed the muffler only just before the Rally. Two day of driving through the mountain's and a day at the track, the exhaust developed a buzz around the 2K mark.
My dealer in Albany was doing the pre Rally service and the exhaust was installed then. He did mention that I would have to check/tighten the exhaust after about 500 mile. So, this buzz I related to something needing tightening in the exhaust. Turns out everything was snug, but the buzz only increased.
So, maybe 6-700 miles , and the muffler seems to develop the dreaded loose internals/buzz.
Like the exhaust and the sound. Hopefully the buzz can be eliminated.
Next step, contacting Borla . Hopefully Pete, yours is the newer version than the one I had.

Bruce

Cracked weld. Gen 1 is more prone to it but I have seen it on both Gen 1 and 2. Borla will replace