Convertibles V6 with aftermarket mufflers: What did you use and how did it turn out?

Did your convertible get drone to a large or small degree? Have you heard in person or read reports from fellow forum members that they did not get drone with your exact set same set up? The only variable my muffler shop guy could guess is that it may be because of being a convertible. Which does not make sense to me, but I can only ask if what other convertible owners have experienced.

(I asked this same thing on the EB and GT mod threads too, on the off chance that exhaust drone ‘convertible effect’ may be common.)

I am curious if your modifications sound different than the same car with the exact same mods in the hard top version of your car. I have significant low frequency (prob +/- 135 Hz) drone after installing just Magnaflow mufflers and tips (rest of car is stock). Others with coupes have reported no drone with these. Russian and DJGolds V6 coupes do not have this Russian Had BBK Shorty headers long before adding Magnaflows. DJGold added BBk’s a few days after his Magnaflows. Besides BBK’s, Russian’s car is stock like mine. I believe DJ’s as as well. Russian and I drove in each other’s cars today. He has zero drone! My tone is lower outside the car than his. So my V6 convertible is somehow producing lower frequency sound at the muffler, even though we both have Magnaflow 11365 mufflers w/ 35136 tips. How could the structure of the car produce a different sound?? No idea. All I can do is ask for real world convertible aftermarket muffler experiences.

The ONLY difference (besides BBK Shorty headers and his being a coupe) between my and Russian’s is that the 2” extension required to fit these shorter than stock mufflers, is that the extension on mine was mounted in front of the muffler and his was mounted between the tip and the muffler’s back end. My muffler shop guy’s opinion:
1) The extension location should have no affect.
2) Headers, if anything might make the exhaust a bit louder, but should not introduce drone.

I am scratching my head on this one!

Thanks,
Dave

Could it be the mufflers? Were they bought from magnaflow or amazon? Maybe one of them is a fluke.

DJGold said:

Could it be the mufflers? Were they bought from magnaflow or amazon? Maybe one of them is a fluke.

Click to expand...

They were purchased from Amazon and came from two different Amazon locations a day apart. I called Magnaflow to verify they were 11365's not 13366's (2.5" in/out). At least as far as the p/n and reference #'s (on the Magnaflow boxes, not mufflers), they are the same 11365's as Russian's. I also confirmed when I saw & drove Russians car yesterday, that his in/out pipes are exactly the same as mine. If they were bolted on, I would eat the return shipping to try another set. But these have hangers welded on and are welded to the factory pipes.

They are just straight thru's. Hard to mess up, but who knows. Good thought as we stretch for reasons. Tks

If anyone knows of someone besides Russian, DJGold and ajfrench with Maganflow 11365 mufflers on their V6, PLEASE let me know.

On 4/5 I PM'ed ajfrench, but now I see he has not been here since 3/28. :( (I just PM'ed an admin to see if they might be willing to try contacting aj)

After trying many different tips (5", 7" 9" resonated and regular) AND cutting the 11365's** off to try to slide them forward a bit, I believe they shipped my 11366's (2.5" inlet/outlet not 2.25"). I have no idea if just the slightly smaller inlet and outlet would create drone or not. Both mufflers have the exact same 2'5" inside pipe! I tend to guess not. I may try to order a pair of the same straight thru muffler that is 3" longer (11226, 2.5" I/O). I'd go with 2.5" now, because my muffler shop added a 2.5" o.d. extension to my tailpipe to adapt up to the 2.5"** .i.d. Maganaflow mufflers I received.

So a while back I spoke to Magnaflow a few times trying to see if they might have sent me 2.5" mufflers. He totally ignored the dimensions I had on mine and said if your boxes say 11365, they are 2.25" 11365's. He asked for the s/n (on box not mufflers! ) and confirmed they had to be 2.25"ers. "We run one muffler at a time and boxes cannot get mixed up."

Yeh, well maybe the 3rd party seller changed boxes... I'll never know.
But I am pretty sure I got 11366's.

I am now thinking it really is the convertible that makes the low resonant sound, which is awesome from out side, a problem on a convertible.

I am now thinking it really is the convertible that makes the low resonant sound, which is awesome from out side, a problem on a convertible.

Quite possible. Here is a link that touches briefly on the fact that the tester thought the GT vert sounded louder from inside than a GT coupe.

http://www.theglobeandmail.com/glob...-more-of-a-laid-back-cruiser/article24327051/

Well Dave my car came in. Regardless of how my soon to be installed Magnaflow 11365 plus tip end up sounding, it's at least gonna look better than this ..... hard to believe. A little more detail in the BUILD section 4/27

Blaster,
Thanks for the article referencing the convertibles sound difference. I had previously thought of the low resonace drone sound as coming up thru the car not in from the roof because it seems more noticeable with the top up than with it down (even more outside exhaust noise available to the ears). But this article makes me think that the drone seeming less obnoxious with the top being 'down' may only be due to the added ambient and wind noise obscuring it to some degree. The top is good at keeping outside wind etc. noises out. But there is NO keeping out low frequency sound waves as they easily pass thru walls etc.

It will be VERY interesting to hear your outcome. It seems weird to have been complaining about my 11365's for the past five weeks, just to get confirmed from the measurements on your (actual 2 1/4" in/out) that my Magnaflows were actually mispackaged 2 1/2" in/out 11366's! ! :doh: ;)

Did you say you were planning on having them installed this Friday?

Dave, the magnaflows should be on by the end of this Wednesday. I still haven't taken possession, but I took it out on the highway today and it's a "tinny" vehicle. Not a whole lot of sound deadening like GM uses. Although, love the car.

I took a look in the trunk and in particular the spare tire area and I've come to the conclusion that I'll be applying Dynamat to the entire trunk area. It seems to me that that spare tire area, which is large, might act as a big speaker box.

Dynamat Xtreme Trunk Kit:

Get the shake, rattle, and roll out of your trunk and let your subwoofer perform at its best. Dynamat's Xtreme trunk kit absorbs resonances in the rear of your car, eliminating noise and creating an ideal listening environment up front for you and your passengers.
Five 32" x 18" sheets of high-performance Dynamat Xtreme reinforce your trunk for high bass pressure capability. Dynamat Xtreme dampens vibrations that would otherwise interfere with your sub's punch and clarity. These lightweight sheets require no heat to apply, and a protective aluminum coating allows them to stand up to high temperatures. Best of all, Dynamat Xtreme reduces noise four times more effectively than its heavier counterpart, Dynamat Original.
Five 32" x 18" sheets, 20 square feet total. Warranty: 60 days.

Blaster said:

Dave, the magnaflows should be on by the end of this Wednesday. I still haven't taken possession, but I took it out on the highway today and it's a "tinny" vehicle. Not a whole lot of sound deadening like GM uses. Although, love the car.

I took a look in the trunk and in particular the spare tire area and I've come to the conclusion that I'll be applying Dynamat to the entire trunk area. It seems to me that that spare tire area, which is large, might act as a big speaker box.

Dynamat Xtreme Trunk Kit:

Get the shake, rattle, and roll out of your trunk and let your subwoofer perform at its best. Dynamat's Xtreme trunk kit absorbs resonances in the rear of your car, eliminating noise and creating an ideal listening environment up front for you and your passengers.
Five 32" x 18" sheets of high-performance Dynamat Xtreme reinforce your trunk for high bass pressure capability. Dynamat Xtreme dampens vibrations that would otherwise interfere with your sub's punch and clarity. These lightweight sheets require no heat to apply, and a protective aluminum coating allows them to stand up to high temperatures. Best of all, Dynamat Xtreme reduces noise four times more effectively than its heavier counterpart, Dynamat Original.
Five 32" x 18" sheets, 20 square feet total. Warranty: 60 days.

Click to expand...

I was blown away at all the untreated sheet metal in this car (esp. the trunk. I was considering doing like you describe, but even off brand dynamat products aer very pricey. I think I calculated 12 sq ft to do the spare tire well and flat areas to each side. The material I was looking at was 4mm thick and about $25/ sq ft. Plus, I read this material is very heavy. I am curious how much weight it adds. With the weight and cost, I am less interested in trying this, then to find out it had little no effect.

If it does not add more than say 30 or 40 lbs and really makes a difference, then it is worth the expense easily to me.

Best I can ascertain is that 5 sheets of the following:

http://www.amazon.ca/Dynamat-19405-...&ie=UTF8&qid=1431396960&sr=1-5#productDetails

has an "Item" weight of 4.3 KG which is 9.5 lbs.

I'm not going to carry a spare. I will carry an aluminum factory Porsche jack that I held back on my recent sale of same. It's feather lite. I'll carry the factory air pump and some plugs. I have CAA/AAA and 200 miles one way flat bed service.

Blaster said:

Best I can ascertain is that 5 sheets of the following:

http://www.amazon.ca/Dynamat-19405-...&ie=UTF8&qid=1431396960&sr=1-5#productDetails

has an "Item" weight of 4.3 KG which is 9.5 lbs.

I'm not going to carry a spare. I will carry an aluminum factory Porsche jack that I held back on my recent sale of same. It's feather lite. I'll carry the factory air pump and some plugs. I have CAA/AAA and 200 miles one way flat bed service.

Click to expand...

I sure hope you wait to hear what your mufflers sound like before adding the sound deadening material. I need to know.
I am also very interested in the results after you apply the sound deadening too.

OK Dave, the magnaflows are installed. As per the first pic taken at the dealer one can see how messed up the pipes were. This caused much difficulty installing the Magnaflows as the pipes attached to the resonator to the muffler where not symmetrical in the least. However, the shop got them on.

Pipe details: the engine side of the muffler was cut off about 1 1/2 inch. A smaller pipe extending thru the tip was then slid into the stock pipe (from the resonator). It was clamped. I think they had the resonator on and off the car 3 times attempting to equalize the flawed pipes. So far that was/is the only problem with the car. Everything else is flawless.

The pipe that was slid thru the tip terminated 3.15 inches (8 cm) from the street side of the tip end. It then went back thru the entire tip and into the street side of the muffler where it was welded.

Results: Fantastic. Very deep, deep, sound. Zero rasp. Loud? Nothing as loud as your vid. Drone? It's louder at highway speed than stock, but not intrusive. My sedate sister thought it was great; radio/conversation no issue.

I'm very pleased. Thanks for leading the charge. The Dynomat is certainly on the back burner. I'll do it when I feel the need to burn some money. But right now I'm going to order a set of Steeda springs.

Here comes some pics.

Blaster,
Congratulations on your good sounding exhaust!!!!! :cheers:

Will you be able to do an interior and exterior sound clip for us soon?

A few questions to see which differences between yours and mine that I can try to duplicate.
The two main differences is see are:
1) You used even smaller diameter pipe inserted into the 2 1/4" tailpipe (from resonator.) That joint like mine is right at the bend and the pipe is 'not' round, so getting the next sized pipe (2") to slide inside even an inch might not fit. I wonder if he might have used 1 3/4" pipe even??

a) do you know the o.d. and aproximate length of the inserted sleeve pipe used to connect the muffler to the tail pipe? So how far into the muffler and into the bend of the tailpipe?
b) Do you know the o.d. of the pipe and how far 'into' the muffler it was inserted? (all the way up to the bend inside muffler or just some way into the muffler's outlet connector pipe.

2) Your tips protrude much further than mine. Measuring from the to center of the tip to the 'outside' edge of the cutout lip, mine dimension is 1 3/4". What is yours?

Your inlet and outlets to the (2 1/2") muffler core were reduced from 2 1/4" down to 2" (or maybe even 1 3/4"?). My 11366 inlet is 2.5", as is the extension/connector on the front. My outlet that the tip is connected to is also 2 1/2". With 1 1/2" cut off the inlet side of your muffler and the longer connector I have there, my muffler is probably 2 1/2" further back than yours.

When I know the size of your 'insert' pipe connectors, I'll look to duplicate that on mine and move them further forward.

What tips are those? You went with something different than the MF 35126's that Russian and I (initially) used.

davekro said:

Blaster,
Congratulations on your good sounding exhaust!!!!! :cheers:

Will you be able to do an interior and exterior sound clip for us soon?

That would be a job for my son. I have no clue as how to do that. :eyebulge:

A few questions to see which differences between yours and mine that I can try to duplicate.
The two main differences is see are:
1) You used even smaller diameter pipe inserted into the 2 1/4" tailpipe (from resonator.) That joint like mine is right at the bend and the pipe is 'not' round, so getting the next sized pipe (2") to slide inside even an inch might not fit. I wonder if he might have used 1 3/4" pipe even??


a) do you know the o.d. and aproximate length of the inserted sleeve pipe used to connect the muffler to the tail pipe? So how far into the muffler and into the bend of the tailpipe?

Don't know exactly on the OD. The entire exhaust including the resonator was removed from the car because it had an errant bend from the factory. See first pic above. They had to fit and remove the entire section 3 times before they got it straightened out. They were getting frustrated as it was an awkward two man job. I gave them space. I know they cut about an inch or so off the muffler inlet and did some flaring. As for the exact pipe they used to connect the muffler to tail pipe I do not know, but it was heavier gauge and a tight fit.



b) Do you know the o.d. of the pipe and how far 'into' the muffler it was inserted? (all the way up to the bend inside muffler or just some way into the muffler's outlet connector pipe.

Just enough into the outlet/inlet to secure it I would assume.

2) Your tips protrude much further than mine. Measuring from the to center of the tip to the 'outside' edge of the cutout lip, mine dimension is 1 3/4". What is yours?

4 1/4 inches more or less. Difficult measurement to be super precise.

Your inlet and outlets to the (2 1/2") muffler core were reduced from 2 1/4" down to 2" (or maybe even 1 3/4"?). My 11366 inlet is 2.5", as is the extension/connector on the front. My outlet that the tip is connected to is also 2 1/2". With 1 1/2" cut off the inlet side of your muffler and the longer connector I have there, my muffler is probably 2 1/2" further back than yours.

The "shop" pipe inserted thru the tip into the muffler and welded was 2 1/4 OD and 2 1/8 ID. That I know and measured. The "shop" pipe between the muffler and the pipe from the resonator I did not measure but PIC enclosed.



When I know the size of your 'insert' pipe connectors, I'll look to duplicate that on mine and move them further forward.


What tips are those? You went with something different than the MF 35126's that Russian and I (initially) used.

Click to expand...

Those are 35126. Right off the box. Dave, the biggest difference between our setups is that my tips are out much further than yours and I have that 2/ 1/4 inch heavy gauge pipe running thru until 3 1/8 inch from the street side.

Blaster said:

Those are 35126. Right off the box. Dave, the biggest difference between our setups is that my tips are out much further than yours and I have that 2/ 1/4 inch heavy gauge pipe running thru until 3 1/8 inch from the street side.

Click to expand...

Blaster,

My bad on using an errant MF tip p/n. :doh:
The MF tips initially installed on mine were 35136, not 35126, sorry for the confusion.

But this part is really hard to make sense of:
"The "shop" pipe inserted thru the tip into the muffler and welded was 2 1/4 OD and 2 1/8 ID. That I know and measured. ...."
because the outlet pipe on you muffler is 2 1/4" and the spec from MF on your 23126 tip's inlet is also 2 1/4". Yet in your picture the connecting pipe fits inside both of those. And looks to do so maybe even with a loose fit? Weird.

First picture below is shows my MF 35136 tip installed, with the top of the 15º angled tip being maybe about 1 1/2" from the outside of the cut out. (vs. yours at about 4 1/4").

Second pic is AJfrench's (same tip and muffler as yours), but his tip appears to be mounted in 1 1/2" or more in from yours comparing the back edge to the lower body piece. And Aj reports very mild if at all drone. Maybe the tip further out does lessen drone.

Third pic below is a blow up of your muffler to tip sleeve.

OK Dave, I'll grind this out best I can.

My initial intentions where to photo record the entire procedure in an organized fashion. But after it was discovered that Ford's screw up on the driver's side exhaust was no simple hanger adjustment and required the resonator on back to be taken off and re-installed 3 times, those plans went astray.

But this part is really hard to make sense of:
"The "shop" pipe inserted thru the tip into the muffler and welded was 2 1/4 OD and 2 1/8 ID. That I know and measured. ...."

I'm attempting to describe the pipe that was supplied by the shop and inserted thru the Maganflow 35126 and into the muffler outlet. It was a tight fit in the tip and then they flared it in this machine so it would be fairly tight in the outlet. Then it was spot welded ... not to my exact liking either.

So the question might arise; why did I have this "pipe' inserted so far into the 35126? Well after fooling with it I thought the 35126 acted a bit like a megaphone so the inside pipe might nullify this a bit. I also thought that the further away the street side of the 35126 was the better chance for less drone. I also like to see these tips.

In summary, when travelling along at 60 mph in 5th or 6th, under a slight load, the exhaust sound in the interior with windows up , is slightly higher than stock. But that is only logical. The sound when you want it is very deep. This is one of those "shot in the dark" actions that met it's target as some of my experiments don't turn out as desired. :lol: