Exhaust Heat insulation orientation

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DavidE9
Posts: 254
Joined: Apr 22, 2012 1:29 AM
Location: 34.138016, -117.214714

Exhaust Heat insulation orientation

Post by DavidE9 »

Hello:
I'm replacing the insulation under the car that runs above the exhaust and below the transmission tunnel. Part #1 as show here:

https://www.realoem.com/bmw/enUS/showpa ... 1481875998

Is the orientation in the diagram correct in that the "V" cutout in the piece is toward the back of the car ? I cant seem to get the factory holes in the insulation to line up to the mounting speed nut studs under the car. Easy enough to create a new hole in the part I suppose, but I thought I would ask first.

TIA
Blue Shadow
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Location: SE PA

Re: Exhaust Heat insulation orientation

Post by Blue Shadow »

The diagram appears correct.
e24 from the web:
https://www.bing.com/images/search?view ... 11&iss=VSI
Mike W.
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Joined: Feb 12, 2006 12:00 PM
Location: California Whine Country

Re: Exhaust Heat insulation orientation

Post by Mike W. »

IIRC that Vee is so it doesn't rub on the driveshaft.
DavidE9
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Joined: Apr 22, 2012 1:29 AM
Location: 34.138016, -117.214714

Re: Exhaust Heat insulation orientation

Post by DavidE9 »

Well, Im not sure what to say but when I installed the shield with the V toward the front of the car, the holes in the part lined right up with the speed nut studs under the car.
vinceg101
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Location: Los Angeles, CA

Re: Exhaust Heat insulation orientation

Post by vinceg101 »

Well, the V split definitely goes to the rear:
Image
Image
Image

Because when you get the exhaust in, the square end needs to be in front:
Image
Image
DavidE9
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Joined: Apr 22, 2012 1:29 AM
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Re: Exhaust Heat insulation orientation

Post by DavidE9 »

First off, your car looks very clean! I hope to get mine looking as good someday. Looks like you replaced your speed nuts. May I ask where you found them ?

Here are photos of what Im dealing with. My middle stud doesnt line up with the factory holes in the heat shield. Easy enough to create new ones I supposed, but this is strange.

Front:
https://share.icloud.com/photos/0bbEXmX ... BL_f0OEk5Q

Middle
https://share.icloud.com/photos/042ICN9 ... ahITjvUWVw

Rear
https://share.icloud.com/photos/095fCSf ... 6RGhNSuJkQ
vinceg101
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Joined: Jun 20, 2007 2:40 AM
Location: Los Angeles, CA

Re: Exhaust Heat insulation orientation

Post by vinceg101 »

Those are just large fender washers with regular M6(?) nuts (pretty sure they might be nylock nuts); I likely bought them at Belmetric.

Not seeing your overall pictures of the heat shield, but one thought is that it's just distorted somewhat. The piece is very malleable and soft and is kind of prone to getting out of it's proper shape. That could lead it to not align to the mounting studs. I would try massaging it a little and see if you get the holes closer to the studs. I had to fix mine when I unpacked it from the supplier, it was kind of dented and bent with a lot of wrinkles in it. You kind of have to flatten it a bit which pushes the edges out, that gets the holes closer if I recall.

That clean undercarriage cost me a lot of brain cells, just look it up in my build thread. Those pictures are also 9 years old so I can say it doesn't look that clean anymore. But thanks for the compliment!
Mike W.
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Joined: Feb 12, 2006 12:00 PM
Location: California Whine Country

Re: Exhaust Heat insulation orientation

Post by Mike W. »

vinceg101 wrote: Dec 13, 2024 2:44 AM Those are just large fender washers with regular M6(?) nuts (pretty sure they might be nylock nuts)
Yes on both and an odd curiosity is the washers are stainless.
vinceg101
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Joined: Jun 20, 2007 2:40 AM
Location: Los Angeles, CA

Re: Exhaust Heat insulation orientation

Post by vinceg101 »

Mike W. wrote: Dec 13, 2024 1:37 PM
vinceg101 wrote: Dec 13, 2024 2:44 AM Those are just large fender washers with regular M6(?) nuts (pretty sure they might be nylock nuts)
Yes on both and an odd curiosity is the washers are stainless.
Well, these are just yellow zinc steel as are the nuts (although SS would make more sense).
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