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under floor insulation

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maxwedge5281

maxwedge5281

Jedi Warrior
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i have one of those nasty boy conversions and still dealing with the heat. i have dynamat inside on the tunnel, floors, and footwells. i removed carefully the original healey asbestos material beneath the floor and now i am ready to replace. after a search i saw hardiboard mentioned as a replacement material. anyone with experience with this or some other board type material. i do not wish to buy precut factory type pieces and will cut and fit my own!!! suggestions or other insight solicited! and, thanks in advance for your comments!!!
 
Hardiboard works perfect, and looks just like the original. I think it is what MOSS sells as a kit for heat proofing. I also put foil coated bubble wrap as a spacer for the Hardiboad. Seems to work for me.

Jerry
BJ8
 
i think that hardiboard comes in different thicknesses....any recommendation regarding thickness?
 
If you want to be close to original you can use this: https://www.lowes.com/pd_122449-342...&CAWELAID=1210289564&kpid=3071699&CAGPSPN=pla

I used this self-sticking product: https://www.summitracing.com/parts/dei-010412/overview/

IMG_0196.jpg



IMG_0209.jpg
 
AFAIK, all the aftermarket replacements for asbestos shields are made of 'hardiboard;' though, I think it may actually be the product called HardiBacker:

https://www.jameshardie.com/homeowner/products_backerboard_quarterInch.shtml

Don't think you can do better than this--given the people who contributed to this product--but I know you're not so inclined:

https://www.mossmotors.com/Shop/ViewProducts.aspx?PlateIndexID=93519&SortOrder=10

Nothing compares with asbestos for heat shielding or fire prevention, though obviously it's too much of a hazard to continue using (but not a danger if it's not disturbed--I still have the original panels on my BJ8 except for the exhaust manifold heat shield and don't lose any sleep over it).
 
I used 1/4" Hardi Backer, a product sold in sheets by Home Depot and intended, as I understand it, as a backer for ceramic tile. My '60 BN7 was missing all of the insulating panels, but I found patterns for these at Healey6. I made one deviation, choosing to make the piece installed above the muffler to a size filling the full area between the frame members. I removed the muffler and the trailing pipes for this installation. Here I also made small spacers drilled for the attaching bolts, adding a couple of additional ones in a larger spaces. These are intended to isolate the Hardi Backer from the floor above the motor. Installing the several pieces that can be attached to the foot well from below and those that install in the engine bay would best be done with the engine out of the car, but it can be done. I also chose to wrap my exhaust pipes from the manifold to the front of the muffler to the manifold with a wrap made for this purpose, securing the wrap with stainless steel cable ties. I can't assess the success of this work, as it is generally hot here in north Florida, and these are hot cars.
 
RDKeysor said:
... I also chose to wrap my exhaust pipes from the manifold to the front of the muffler to the manifold with a wrap made for this purpose, securing the wrap with stainless steel cable ties. I can't assess the success of this work, as it is generally hot here in north Florida, and these are hot cars.
Click to expand...

I did that too and, if nothing else, it LOOKS cool!

One thing I noticed after wrapping the down pipes is now my exhaust out the back is hot as a pistol, whereas as before it was just pretty dang warm.
 
i have full length...long tube headers.. on my car and they are wrapped from the exhaust port to the muffler and held on place with stainless ties. i am considering removing and replacing with a much simplier header syste. seems to be tubes everywhere in a very small engine compartment.
 
Heres another thread on this topic:
https://www.britishcarforum.com/bcf...nd-other-hot-topics&highlight=muffler+blanket
In it I posted my pics of my heat abatement which I must say is working very well. One area often overlooked is the small area of floor pan ahead of the first outrigger. I made a hari-board panel to protect that area as well. I also have the heat shielding material stuck to the bottom of the floor pans as well as the inside passengers compartment. the hardi-board panels hide the silver dynamat material. I think if you also have mufflers right under the seats, using a heat blanket like I did is wise as the mufflers tend to act as radiators, holding the heat, where-as the pipes themselves are only hot for a while because the exhaust is traveling through them.
Jim
 
Thank you sir. Much more reasonable than i suspected. i don't think I ever saw their site. Nice looking stuff.
Chris...
 
I recently got given the lining panels of a chemical storage cabinet . It looks exactly like the original asbestos board . Its the same thickness but it isn't asbestos as the people giving it to me had it tested but they decided to get rid of it anyway as it looks to much like asbestos .
So when it come time to do the Tri Carb I will be making my own and some extras to cut down on the fried feet syndrome .
Cant beat FREE .....
 
One of the best suggestions I ever saw to cool off a Healey was to hang a droplight in the engine compartment and go into the interior and see where the light shines through and plug the holes. Lots of places on the firewall to let hot air in. Keeping hot air out of the Healey interior is a lot like Hans Brinker plugging the dike.
 
Good idea Rick. The air flow through the firewall can be hot, I was feeling a nice hot stream on my right foot from the MG's accelerator opening and it's fairly tight. OAT was 100F, but still.
Chris...
 
For my insulation MOD I have followed this thermal photo https://picasaweb.google.com/112770...ATIONAUSTINHEALEY10061958#5369038515512638146
Here is clear that the critical heat point are nearest the foot of the driver (150°F)on LHD cars- where the AH projectists OMITTED the insulation
This is the piece that I have easy added to my car
https://picasaweb.google.com/112770819864514987162/REBUILDINGAUSTINHEALEY10061958BeginningMayJune2011endMayJune2013?noredirect=1#5626281281308008706
and that are the pipe insulation added
https://picasaweb.google.com/112770...dMayJune2013?noredirect=1#5711557515011699346
https://picasaweb.google.com/112770...dMayJune2013?noredirect=1#5717210010154678386
result on pratica driving the car for more than 500km without interruption are very good- a lot of insulation was added also at the muffler upper side panel
This sketch can help on cutting the upper insulation
https://picasaweb.google.com/112770...MayJune2011endMayJune2013#5646705418191094082
 
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