I loved the quiet engine in the 25 Nautilus Hybrid, it's much better than the RXH and I found a product that has deadened the noise considerably. It's called the ResoNix Fiber Mat Silver - Car Hood Liner & Sound Absorber https://resonixsoundsolutions.com/pr...IcW7vMwA-KEdoW
It was well worth the $115 cost. I didn't stick it to the underside of the hood as shown on their website but instead placed a sheets of heavy duty foil on the sticky side and placed the mat on top of the engine. I think this helps do a better job absorbing the sound waves and can be removed at any time. I'm not worried about trapping heat, Lexus covers all of their LS sedan engine compartments in plastic covers ( I have the LS 430 and 460) and since it's a hybrid, the engine can't build up excessive heat standing still with no airflow as the engine turns itself off.
Thought I would pass this along for anyone else that shares this concern.

 

For a hybrid, I'm not sure, but don't do that to your turbo engine, it does need air flow to the back of the engine to cool the turbo. The engine cover is not just for the look but to control air flow.

 

Doesn’t seem like that blanket would do anything to lessen engine noise heard in the cabin.

 

Every engine and drivetrain is designed to have airflow cool is components and computers. Engine ECUs for example are mounted next to fuse box and has great dissipating fins that need air flow.

This might be a very expensive experiment.

 

 

My partner had a Mercedes that came from the factory with no insulation on the hood and we installed Dynamat Hoodliner and it did make a noticeable difference in engine noise. It doesn't completely eliminate noise, by any stretch, but it does lessen it. We installed it per the instructions, though, and adhered it to the underside of the hood. Personally, I would be weary of leaving it loose on top of the engine. I don't want to block airflow in a tightly-engineered area, nor do I want any of it to get caught in a belt.

 

I thought you sold the RX and bought the Lincoln(?)

 

He posted in that other thread that he changed his mind.

 

He posted in that other thread that he changed his mind.

 

It works, the groan of the engine has lessened considerably.

 

Changed my mind and explained reasons in the other thread.

 

There is nothing moving in the engine compartment that it could come in contact with and the hood when shut keeps it in place. I am considering your comments on airflow and will take another look at that. Thanks for the input.

 

Great input, I'm reconsidering which is disappointing as this has really helped quiet the engine.

 

I took the sound deadening material out and took it for a 20 mile drive and have decided to leave it out for now and may consider trimming it and attaching it to the hood in the same shape as the current OEM material. This will avoid air flow issues that have been brought up in the comments. The sound improvement was only slightly noticeable (perhaps I had observer bias initially) and is certainly not worth risking any premature wear to the engine. Thanks to everyone's input, I stand duly corrected!

 

If this engine is the same as in the 7ESh, the older pre-refresh ES had much more engine cover padding/foam. i would try to use that part if it fits. i remember when the refresh hit, lexus changed out to a new cover that had way less foam. i'm not 100% sure if the engine or engine configuration is the same but it could work or modified if need be.

Click on the pics til you see the underside.

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