Underhood Insulation Upgrade Keeps the Peace Better Than Sheriff SkyPup

Recently, I upgraded the underhood insulation on Ol' Silver by adding 2 1/2" of extra foam padding as sound insulation.

Here are a few pics of the job:



Note: The OEM black clips will work with an extra 1 1/4" of insulation, but not with the 2 1/2" padding that I preferred.



Two pieces of foam insulation were placed together and held in place by 3/8" bolts (1" long) with oversize washers and teflon nuts strategically placed in the same slots the plastic OEM fasteners came out of.

How's that sound advice!

Engine is quieter as confirmed on a test drive, but as for "how quiet?", it's too soon to tell.

If Ol' Silver breaks the sound barrier, I'll let yah all know!

Good idea TS, never thought of that one. Is the foam just regular insulating foam from Home Depot, or is it something special?

I think I will try this, the A3's are a little louder than the A4's.

This doesn't interfere with you motto; get cool air in.....

Steve, won't that increase engine bay temps...something I believe you've posted in opposition to? Just curious. Might you take temp readings?

I doubt that engine bay temps will go up much at all. Mine is well ventilated and this is a nonissue for Ol' Silver. Adding more inexpensive foam from Walmart to the underside of the engine compartment might be considered too. The area I had in mind is insulating the inside portion of the black plastic wrap-around piece which the Lower Engine Cover attaches to.

If you don't like the diesel sound, why the heck did you buy one???!!!