Bonnet sound deadening

[cococola]

I am removing the remainder of the adhesive that held the sound deadening under my bonnet lid and will hopefully polish the underside to a decent finish.My queery is just how much does the deadening improve the 944 as I have never had any on mine since ownership.

 

[JayKayEm]

I replaced all the foam bonnet deadening on my 1986 Lux. It just turned to powder and disintegrated to dust when you touched it. Very unsightly.

I was working to the strategy that if it had it on when it left the factory, it must have it on now.

As to why, I have no idea. You could guess at either noise or heat control for the painted surface on the other side. However, not all 944's have that deadening - later cars didn't. My S2 didn't.

I paid a considerable sum for essentially two bits of foam, which were still available from Porsche.

You could still hear the timing belt whine with the new foam too! []

Good luck with the cleaning - mine was a right pain!

 

[fulvia]

Had the same issue as JKM, when you touched it it disintegrated and loads of powdery bits would gather in the engine bay. So, I removed all the foam the other week, but haven't noticed any difference to noise levels. Can't say about heat though.
I still have the adhesive residue left however. But, not sure if I can be bothered to remove it. Did you find a quick way?
Ian

 

[poprock]

My first two 944s had the foam. My current Turbo doesn't. There's not a noticeable noise difference, but there is a fairly big difference in bonnet heat! I rather like the way rain turns to steam on the bonnet of the Turbo though.

 

[Suffolk944]

Yes I would agree with Poprock. My first turbo had the foam, my current one doesn't and I really can't say it makes a jot of difference noise wise. The steaming bonnet in the rain is pretty cool though ! []

 

[graham.webb]

My S2 doesn't have it and looks like it never did, so I guess it's OK not to have any?

I recall early cars getting bad press (probably 924s come to think of it, especially in dark colours) for having fuel injection problems in the hot climate in the US....perhaps that's what it's for? Some US websites (Pelican or Paragon??) sell the Weltmeister reflective liner.

The car's quiet enough, surely? On the other hand there are people who'll happily spend money on an exhaust to make it louder....

 

[cococola]

Thanks for the advice guys I will continue with the cleaning option[] the best thing to use is petrol I have found although it is hard work I have done a bit left a bit and it is starting to look better[]

 

[JayKayEm]

Yep, thats it, petrol. Petrol was the only stuff that would touch the horrible gunk residue. I did get high as a kite though and had to continue outside the garage rather than in!

I put a sheet over the (cold) engine bay to stop the mess laying on top of the engine.

 

[cococola]

My valeting mate gave me some autoglym tar and glue remover and it works a treat today cleaned everything off the hood and polished/waxed it aswell......well worth it[]