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While changing my oil this evening, I thought I would have a look at a loose bit of heat shielding in the back which had been causing an increasingly frequent rattle when driving over rough roads.

Or at least I thought it was loose heat shielding. It turns out that my Larini muffler had broken in two places!

On each side of the muffler is a hanger that is composed of a length of approx 3/8" rod. The hangers on each side are held in rubber donuts which are in turn bracketed to the rear subframe.

The LH side hanger is a 12"-14" length of rod that is welded to the muffler body and, at about the midpoint, to a small tag on the pipe upstream of the muffler body. On mine, the hanger had come adrift from the tag, and then wiggled and vibrated until it finally work hardened and fractured near the muffler body weld. Although the hanger on the other side was still intact, the muffler was free to bump around, making a sound very much like loose bodywork or a poorly-latched tailgate.

Fortunately there's a flex joint upstream of the bottom catalytic converter, so the movement of the Larini unit didn't cause any stresses on the rest of the exhaust system-- cracks would have been the sure result otherwise.

The fix was pretty easy. I pulled the muffler and the broken hanger, clamped the latter back in position, and laid a few beads on the midpoint bracket and around the stress fracture with a MIG welder. This is not a recommendation-- welding stainless steel is a bad idea unless you have proper breathing equipment, so don't try this at home, kids. But be aware that the fix is simple and any decent repair shop can take care of it for you in short order. And yes, it is important to remove the unit from the car before welding, unless it's done with oxy-acetylene.

Just thought I'd mention this in case any Larini-equipped Evorae are out there making a funny noise. The only annoying thing about this job was that when I was finished, the oil was still slooowly draining out of the Fumoto valve...
 

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Did you try to contact Larini as they usually come with lifetime warranty.
 

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One of the main issues i noticed on that car was the engine mounts. I dont know if yours related with that but you can just check how mush the engine moves back there, even while starting. On hard accelerations and/or high speed cornering all the engine, manifolds, 3rd cat and muffler moves a lot and that can cause some damages hopefully my cracks was on the welded corners of the muffler. Also that causes harder gear changes on the situations a mentioned below. I checked for Evora S mounts which are harder but they were out of stock when i checked so gone custom with evo and mini mounts, even more hardened with metal plates on them.
 

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What size Fumoto oil pan valve for an Evora?
 

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Discussion Starter #5 (Edited)
One of the main issues i noticed on that car was the engine mounts. I dont know if yours related with that but you can just check how mush the engine moves back there, even while starting. On hard accelerations and/or high speed cornering all the engine, manifolds, 3rd cat and muffler moves a lot and that can cause some damages hopefully my cracks was on the welded corners of the muffler. Also that causes harder gear changes on the situations a mentioned below. I checked for Evora S mounts which are harder but they were out of stock when i checked so gone custom with evo and mini mounts, even more hardened with metal plates on them.
Well, as I mentioned, there's a flexible joint upstream of the silencer. I don't think any engine movement would get translated all the way through the exhaust system.

I also don't understand how engine movement can affect gear changes in a car with correctly adjusted shift cables. Tension on the cable sheath should not change with engine movement, again assuming everything is correctly adjusted. That is why, for example, motorcycle brake cables work despite a range of motion on the forks or swingarm that may be several inches.
 
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