• Hey Guest!
    British Car Forum has been supporting enthusiasts for over 25 years by providing a great place to share our love for British cars. You can support our efforts by upgrading your membership for less than the dues of most car clubs. There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Upgraded members don't see this banner, nor will you see the Google ads that appear on the site.)
Tips
Tips

Fire wall insulation

Share this page

D

Dealmaker5

Freshman Member
Offline
Hello does any body have an idea of how to get a pattern for the firewall on a Healey , the insulation that looks like hardee backer cement board
 
Yes it looks like Hardibacker but hardibacker actually has no thermal insulating properties. I'd love to know if the stuff sold by Moss has any insulating properties either.
 
I don't know why you would even need it? As long as you insulate the floors, toe boards, and transmission tunnel you should be good to go. I seriously doubt if the stock one does any good, being asbestos it is more of a health hazard then anything. But if you must, I would just go for the moss kit.
 
drambuie said:
I don't know why you would even need it? As long as you insulate the floors, toe boards, and transmission tunnel you should be good to go. I seriously doubt if the stock one does any good, being asbestos it is more of a health hazard then anything. But if you must, I would just go for the moss kit.
Click to expand...

You can make a big improvement, even on a concours car, by ensuring the grommets are in place and sealing properly at the top portion of the firewall. Shine a droplight in the engine compartment and look up under the dash. Wherever the light shines through is a path for really hot air to come into the passenger cabin. You'll be surprised how many "points of light" you'll see.
 
I used Hardibacker for under the floor boards and used the Moss product for the firewall and driver's footwell. While Hardibacker may not have good insulation value, remember that if installed correctly these pieces have spacers behind them providing an air gap and will block radiant heat if not convective heat. So they do provide "some good".

Griz
 
Good comment Griz. I've considered hiding a foil layer on the backside of the insulation in that air gap. I don't think you'd be able to see it and the foil would create a true radiant reflective layer in that airspace. I'm thinking it would help dramatically. Just an idea...
 
Dealmaker5 said:
Hello does any body have an idea of how to get a pattern for the firewall on a Healey , the insulation that looks like hardee backer cement board
Click to expand...

You didn't say what model of Healey, but Moss has kits for the 100 made in collaboration with Roger Moment, the Healey 'Guru of Gurus.' Wish they had them when we restored our BN2.
 
I disagree that hardibacker has no insulation properties. This is even better with the air gap spacers and with the addition of some silvering . It has worked well for me both on the engine space bulkhead and on the carb heatshield which was just a sheet of steel before my additions. I,m sure there are better products but this stuff does work. However I do agree with proper bulkhead sealing and insulation of footwells etc with something like cooltec or dynamat too.
 
Hardie Board is now preprinted in yellow. I bought the "white" stuff from BCS. It came from the UK and was bight white and I found "master board" on the backside of it. Probably the UK version of Hardie Board.
 
Patrick67BJ8 said:
Hardie Board is now preprinted in yellow. I bought the "white" stuff from BCS. It came from the UK and was bight white and I found "master board" on the backside of it. Probably the UK version of Hardie Board.
Click to expand...
"preprinted" should be "preprimed".
 
As I remember the kit I got from Moss was not big enough to do the large piece under the driver floor board. My original asbestos piece was still good so I reused that and cut the remaining pieces out of the Moss sheet. The Moss sheet cut very easily. All my original pieces were good enough to get good patterns. Have a good day!

John
 
John_Progess said:
As I remember the kit I got from Moss was not big enough to do the large piece under the driver floor board. My original asbestos piece was still good so I reused that and cut the remaining pieces out of the Moss sheet. The Moss sheet cut very easily. All my original pieces were good enough to get good patterns. Have a good day!

John
Click to expand...
i got my kit from BCS and everything fit and it had all the pieces. I like the UK product because it was bright white.
 
I used spacers under the foot shield and above the muffler (hardiboard). As I recall there were no spacers behind the firewall panel or on the side of the toe box. Am I wrong?
 
RestoreThemAll said:
I used spacers under the foot shield and above the muffler (hardiboard). As I recall there were no spacers behind the firewall panel or on the side of the toe box. Am I wrong?
Click to expand...

Here's a picture of the side of the toe box on the driver's side showing the spacers on my BJ7

IMG_0094.jpg

I don't see an outline for the standoffs on the passenger side nor does it look like they are on the firewall, either:

IMG_0100.jpg

It's possible they only used them on the driver's side because that's where the exhaust pipe runs. I still have the original asbestos pieces so I can check them to see, but won't be able to get to them until next month. I'll check back with you then if you're interested.

Because originality wasn't my prime motivation :devilgrin: but keeping the heat of the V8 out of the cockpit was, I addressed the issue with engine-turned stainless steel covers over a layer of foil bubble insulation (Reflectix).

IMG_0118.jpg
 
The firewall one has no spacers. It sits flat on the firewall. The upper two on the footbox also sit flat with no spacers. The one on the side of the footbox, and the ones on the immediate front and bottom of the footbox all have spacers. The one on the floor above the muffler also has spacers. In my picture you can see the spacers on the muffler shield as it is lying on the floor waiting installation.
 

Attachments

  • 2012-05-09 003.jpg
    2012-05-09 003.jpg
    76.3 KB · Views: 182
  • 2012-05-09 007.jpg
    2012-05-09 007.jpg
    78.3 KB · Views: 168
Ok. I'm in for a re do of the panel on the side of the drivers toe box. Somebody (me) put an engine right in the way. That'll be fun.

Spacers do make all the difference. I compare it to the woodstove I have in my shop with cement board behind it. It has over an inch of space between the cement board and the wall. The board gets too hot to touch and the wall behind it is only warm.
 
Search Lowes or Homedepot Hardibacker
 
Back
Top