My 914 does not have a sound/head pad on the engine side of the firewall. I placed a dyno something, a foli/foam core sandwich mat, that sticks to the cabin side of the firewall. What are alternatives to the original mat. The purpose is for 1) cabin heat reduction 2) cabin noise reduction.
The engine is already in the car.
Thanks,
Larry

There's a Dynamat product made for use as a hood pad. Comes in a roll. I just used it on an MB 380SL and it worked well. As it's all one piece, it will be awkward to install on your car with the engine installed. The Cap'n

Thanks Cqp'n.
The dynamat is what I have on the cabin side of the firewall. Any other suggestions?
Larry

I realize you have thought about the Dynmat but here is Dynamat installed on my firewall....

Dynamat on firewall (scroll down a bit)

T

The early cars didn't have any engine side sound pad. That's why early cars often have less firewall rust.

I would reccomend insulating the inside until it's quiet/cool enough for you, and leave the engine side free of any water trapping device. Make sure your rear window seal is good first though!

Thanks Trevor. That is the same barrier I have on the inside. I know it is a subjective question, but do you find it shelters the cabin from heat and sound?
Thanks Royce. That is a very good point. Thus, I was wondering if anyone has used a light weight protective coating, maybe something with rust inhibition. My firewall is presently free of rust, and it would be nice to keep it that way.
Royce, is that an aftermarket shifter for the 901 sideshifter?
Larry

Race quiet ear plugs... They are like foamy ear plugs but the center in hollow and the ear phone from Ipod or CD player makes like tolerable for 3+ hours going to an event.

I'm going to try a product called "quietcar" on mine, but it'll be a while before I know how well it works. It's spray on, and supposedly works better than dynamat. It's waterbased though, so it requires paint underneath,

The shifter is a custom cableshifter for a sideshift 901 that I designed but have not yet tested. After testing I may start making and selling them, but that will be quite some time from now. (the 914 it's going into is almost ready to go onto the rotisserie that I haven't built yet)

Royce, if it is waterbased, will it not retain water and promote oxidation/rust?

It's a water based latex viscowhatever foam. It somehow "cures" as it dries, much like latex paint. Ever try to get water to do anything to latex paint once it's dried? It changes somehow into something that isn't water soluble at all. I haven't been able to find anything bad said about it, besides the price.

Your right it is subjective and heat reduction was my intent. It does help, again no science rather seat of the pants analysis, and it may be a bit more quiet.

How is it for you on the inside? I have some Dynamat left over and I was going to put it on the inside.

Let me know.

T

On my inside firewall I used that mutlipurpose industrial insulation... foil on one side, carpet padding on the other. It seems to help quite a bit, but I used 2 layers. I probably should have put down a layer of Dynamat Fatmat (ebay) first, then the insulation. I think when I eventually do my engine pull, I'll rhino liner the firewall.

Oh yeah, factory sixes don't have firewall padding on the engine-bay side.

I used Quietcar on my floorboards and in other cars. Good stuff as an alternative to dynamat / fat mat. I'd suggest using POR or rust preventive paint and then applying the Quietcar. If you're gonna spray, you probably need six to eight coats. Try brushing it on, as it goes on thicker and you don't have to waste a whole weekend watching the stuff dry.

Mike (in Portland)

If you really need a mat inside that compartment then you need to go marine Bro. I have a marine cowl neoprene/mylar role which not only deadens the sound but also keeps things cool. It costs about 70-90$ and comes in roles 32X54. Product # 39104 at West Marine stores.


Gluck.

Thanks JPB .
I went to "Westmarine.com" and plugged in prod # 39104 and came up with a passive woofer tube.
Plugged in marine cowl and got wind scoops. Do you have another identifier?
Larry

Remember, the best way to reduce noise is to use an agent that is bonded to the surface. Thus something like DynaMat (for EXAMPLE) which uses an adhesive to stick to the surface it's applied to is better than a material that you simple stick to the surface using tacks or a smear of contact cement.

Westmarine is sooooo over priced- their target audience is the cheese and wine yachtsman highbrow crowd you know.. there's gotta be somewhere cheaper.

Anyone have experience with several layers of dynamat? Adjust to the noise and heat reduction desired (the subjective thing).
Larry