M&K muffler problem - help please

[haycait911]

I'm having a problem installing an M&K stainless muffler on an 85 Carrera. the muffler is a one in two out with the out pipes side by side a la Singer. stock heat exchangers and cat. stock muffler was in place with no issues and centered.

removed stock muffler, installed the M&K, and the outlet pipes are easily 2-1/2 inches to the left of center. on advice from M&K I loosened all the heat exchanger bolts and the cat bolts. a serious PITA by the way and not something I've ever done just to install a muffler. and chancy with existing gaskets, I expect some leaks now.

with a bunch of wiggling, rotating the inlet sleeve, and a cinch strap pulling the muffler to the right, I was able to get the muffler within about 1-1/2 inches of center.

I measured the stock muffler from center of inlet to center of muffler. then measured the M&K from center of inlet to center of pipes. guess what, I found the missing 1-1/2 inches. the M&K is that much less measuring inlet to center.

an email from M&K was pretty condescending. with an offer to ship it back at my expense to be 'checked'. and certainly not addressing the discrepancy in measurements. they did say this was a 'custom' muffler so no jig could have been used.

I've got two M&K on my cars now and had none of these issues when installing. just took off the old muffler and installed the new one without any loosening of the whole exhaust system. which I find beyond ridiculous BTW. a muffler should bolt on, period.

any thoughts or suggestions? anyone else run into this problem? faced with a $200 shipping cost back to M&K, in addition to the $1200 already paid for the muffler, at this point I'm looking for options to make this work. my thought right now is to install a cat bypass and bend it to make up the difference in the offset.

[patkeefe]

That is some poor quality control on that muffler.

[jbell959]

Hi Don.... I wouldn't be too happy either. I have a few M&K mufflers and haven't run into that issue, but I do have a 2 in-1 out that I wanted to put on my 71 but it interfered with the brackets on the bumpers. I would have thought they would have stepped up and repaired or replaced your muffler at their cost. Let us know what happens.

[snbush67]

Strap on the mounting clamps with the muffler centered without bolting to inlet to the collector. I think you will see that the angle of the inlet may be off a bit.

To correct for the angle, loosen the mounting clamps until you can angle the edge of the inlet on and the start slowly tightening the clamps. Heat will help, maybe pull it with your cinch strap. The clamps are key to pulling the muffler into place.

Also have you checked to ensure your engine is centered, sometimes they move a bit on the mounts.

[haycait911]

Originally Posted by snbush67

Strap on the mounting clamps with the muffler centered without bolting to inlet to the collector. I think you will see that the angle of the inlet may be off a bit.

To correct for the angle, loosen the mounting clamps until you can angle the edge of the inlet on and the start slowly tightening the clamps. Heat will help, maybe pull it with your cinch strap. The clamps are key to pulling the muffler into place.

Also have you checked to ensure your engine is centered, sometimes they move a bit on the mounts.

the pipes aren't even close to being centered on the engine. exhaust moves with the engine.

I tried clamping the muffler in place first. with everything else loose I couldn't even get bolts through the cat holes. miles away. heat and cinch straps are NOT the way to install a muffler. unbolt old, bolt on new.

my first assumption in a case like this is that the part is right and either the car is wrong or I'm doing something wrong. I've exhausted every avenue here. matching up the old muffler and the new is the clincher. I even bolted the old muffler back on to see if anything had moved, it bolted up perfectly centered. the measurements tell the tale in this case.

[motofoto]

I'll have to check the centering on mine, I have the same muffler. I haven't been thrilled with the initial fit either. It hits the bumper shock on the driver's side, so the whole thing is canted downward there. I'm getting ready to do an RS bumper, so I did not spend a ton a of time perfecting the fit yet, but I did take two cracks at it with the same result. We'll see when I get the bumper and shocks off. I will check the centering in relation to the lid like you did here.

[haycait911]

Originally Posted by motofoto

I'll have to check the centering on mine, I have the same muffler. I haven't been thrilled with the initial fit either. It hits the bumper shock on the driver's side, so the whole thing is canted downward there. I'm getting ready to do an RS bumper, so I did not spend a ton a of time perfecting the fit yet, but I did take two cracks at it with the same result. We'll see when I get the bumper and shocks off. I will check the centering in relation to the lid like you did here.

yes. please check yours. more the relationship to engine center. as noted above, the engine can move a bit. although I expect within a 1/4 inch or so.

[A horse with no name]

Hi, did the M&K muffler come with a new muffler braket that replacs the stock one inuding the two stainless round clamps?

[RarlyL8]

These pictures are more helpful to see what is going on than the ones I have received. We do not advertise the 1/GT3 mufflers as they are more tedious to install than the single inlet single outlet version and are mainly sold to mechanics and shops.

The muffler needs to be mounted to the engine with the tailpipes positioned center before anything else is done.

The stock bracket is used along with the clamp included in the install kit. Next the catalytic converter is loosened from the exchangers and the cat outlet bolted to the muffler inlet. In some cases time and heat have caused the OEM system to warp badly enough that it must be loosened and re-aligned. If at this point proper alignment cannot be achieved we know we have done everything prudent and I need the muffler back to check it.

[Cairo94507]

Looks to me like that muffler was not correctly made. M&K should clearly step-up and take care of this. The buyer should not be on the hook for shipping. Now if the muffler turns out to be "in spec" then the buyer has some 'splainin to do". I also do not believe one should have to loosen the entire exhaust system to fit a new muffler. PS - I do like the close dual outlet look.

[Duc Hunter]

Remember that "in spec" on M&K's jig (based on an early motor, not in a car) in their shop, versus fit correctly on a customers car can be very different. M&K cannot be in 2 places at once, and most customers cannot go to their shop for install....so diagnosing these issues can be a challenge on both ends. I had similar issues with an M&K System over the summer. Once we had exhausted (no pun intended) ALL other options they stepped up for me.

Originally Posted by Cairo94507

Looks to me like that muffler was not correctly made. M&K should clearly step-up and take care of this. The buyer should not be on the hook for shipping. Now if the muffler turns out to be "in spec" then the buyer has some 'splainin to do". I also do not believe one should have to loosen the entire exhaust system to fit a new muffler. PS - I do like the close dual outlet look.

[haycait911]

Originally Posted by RarlyL8

These pictures are more helpful to see what is going on than the ones I have received. We do not advertise the 1/GT3 mufflers as they are more tedious to install than the single inlet single outlet version and are mainly sold to mechanics and shops.

The muffler needs to be mounted to the engine with the tailpipes positioned center before anything else is done.

The stock bracket is used along with the clamp included in the install kit. Next the catalytic converter is loosened from the exchangers and the cat outlet bolted to the muffler inlet. In some cases time and heat have caused the OEM system to warp badly enough that it must be loosened and re-aligned. If at this point proper alignment cannot be achieved we know we have done everything prudent and I need the muffler back to check it.

I've already tried everything you suggest here. if the stock system is so badly warped why does the stock muffler fit up perfectly without clamps or loosening? part of the problem may also be that, as you can see in the pic, the inlet pipe is not square to the muffler.

a $200 cost to send it back to you, so that you can tell me it's 'in-spec' isn't really an option.

tell you what. go find a stock muffler for a 3.2. measure inlet to center of muffler, then measure your jig. I spent most of a day struggling with this thing before I compared the two mufflers. I really did assume the muffler was correct.

[haycait911]

Originally Posted by Cairo94507

Looks to me like that muffler was not correctly made. M&K should clearly step-up and take care of this. The buyer should not be on the hook for shipping. Now if the muffler turns out to be "in spec" then the buyer has some 'splainin to do". I also do not believe one should have to loosen the entire exhaust system to fit a new muffler. PS - I do like the close dual outlet look.

I also don't understand why I need to loosen an entire exhaust system, breaking the gasket seal and introducing leaks,just to bolt on a muffler

Originally Posted by Duc Hunter

Remember that "in spec" on M&K's jig (based on an early motor, not in a car) in their shop, versus fit correctly on a customers car can be very different. M&K cannot be in 2 places at once, and most customers cannot go to their shop for install....so diagnosing these issues can be a challenge on both ends. I had similar issues with an M&K System over the summer. once we had exhausted (no pun intended) ALL other options they stepped up for me.

can you tell me a shortcut to 'exhausting all other options? I'm exhausted with this already

I've gotten a few PM's from members that have also had this kind of issue with M&K mufflers. apparently this is not at all uncommon.

[tmaull]

Seems like it'd be a simple task to take a few measurements on the muffler and compare that to the M&K specs. A few minutes taking measurements beats a $200 shipping charge.

[universeman]

Perhaps a video call - Skype or FaceTime - between M&K and the customer where they could see the measurements and adjustments being done, etc., would save everyone some headache? Just thinking aloud...

[ClickClickBoom]

That's why it's called "fitting" with 35 years of welding experience, and plenty of it on stainless, the movement while heating/heated is crazy. If you wanted to correctly "fit" the exhaust, completely remove every component, regasket all joints, loosely attaching all flanges with bolts and nuts. Start pushing, cajoling and wiggling until the correct alignment is achieved. Then slowly start tightening all the joints. Stainless is a fickle *****, and used, heat distorted OEM stuff can be the worst.
When my 3.2 had the stock exhaust system, I removed the cat, and went to install the Fabspeed bypass tube and had to tweak the OEM components back into line to get the Fabspeed tube to line up.

[ClickClickBoom]

Originally Posted by haycait911

I also don't understand why I need to loosen an entire exhaust system, breaking the gasket seal and introducing leaks,just to bolt on a muffler

If you understood, then you would understand. You are not walking on uncharted territory. The guys who have spent a lifetime twisting wrenches understand, that's how it goes and just forge ahead. That's why they get paid a decent wage to do what they do.

[stephen1070]

Originally Posted by ClickClickBoom

That's why it's called "fitting" with 35 years of welding experience, and plenty of it on stainless, the movement is crazy. If you wanted to correctly "fit" the exhaust, completely remove every component, regasket all joints, loosely attaching all flanges with bolts and nuts. Start pushing, cajoling and wiggling until the correct alignment is achieved. Then slowly start tightening all the joints. Stainless is a fickle *****, and used, heat distorted OEM stuff can be the worst.
When my 3.2 had the stock exhaust system, I removed the cat, and went to install the Fabspeed bypass tube and had to tweak the OEM components back into line to get the Fabspeed tube to line up.

This is spot on.

As much as we like exhausts to be 'plug and play' given the variables they are not the latest Iphone IoS version that can be simply uploaded and enjoyed.

For example if you look at one particular famous STR build it's obvious the builder expected the exhaust outlets to be much higher that they ended up given the cut out provisions that were made in the rear bumper in advance of fitting the engine & exhaust.

[Quicksilver]

Years ago I called MK because the outlet on my new single-in/single-out muffler was interfering with the bumper. He explained all that has been mentioned above about welded metal moving around incredibly during the heat of welding plus during the heat of use.

In my case Ben asked if I had run the car with the muffler yet. The answer was "no" so he had me flex the muffler to the desired position. He explained that the heat cycles of use would make the stainless take a "set" but before it has been run it is amazingly ductile. He was right!

The rest of your exhaust system would have gone through all the movement and "take a set" portion of its life so it ended up where it is while being bolted together so they are all ok.

With the new muffler you will need to work with it but I would give MK a call as they will know what you will need to do to get it into spec. Plus if there is an issue they can identify it and they will resolve it.

[snbush67]

Originally Posted by haycait911

the pipes aren't even close to being centered on the engine. exhaust moves with the engine.

I tried clamping the muffler in place first. with everything else loose I couldn't even get bolts through the cat holes. miles away. heat and cinch straps are NOT the way to install a muffler. unbolt old, bolt on new.

my first assumption in a case like this is that the part is right and either the car is wrong or I'm doing something wrong. I've exhausted every avenue here. matching up the old muffler and the new is the clincher. I even bolted the old muffler back on to see if anything had moved, it bolted up perfectly centered. the measurements tell the tale in this case.

Plug and play does not apply to exhaust, don't kid yourself.

Good luck I hope you figure it out. My experience with my M&K product was similiar, it was a PITA to install, and I had to work hard to get it installed right. Customer service was excellent and I even got over the phone assistance, they did everything possible to ensure I was satisfied.