Monzora has a big honkin' V8 where the back seat used to be, separated from passenger compartment by steel firewall. I'm looking to inexpensively reduce heat transfer into passenger compartment. Firewall is made up of flat panels, so should be a pretty good base for stick-on solutions. Junkyard scavenging is 100% within my wheelhouse, so i'm accepting recommendations for vehicles i could rob firewall insulation from.
GO!
Do you have a rough idea of square footage needed?
Look at luxury cars in the junkyard, both for inspiration and materials. It seems that they usually have a multi layer solution of both reflective and then insulation with air space, then rubber layer for mass.
I bet the OEMs have already figured this out, perhaps luxury car firewalls or full size vans where the engine is tucked further back, so a junkyard might be a good place to check. They will probably ring it up as "carpet" which is like $15 for any amount over 3ft at my local PAP.
Mr_Asa said:Do you have a rough idea of square footage needed?
Im beating a dead horse here, but I ask because this is $0.38/ft^2
And it does this level of heat prevention. (Bottom foot-ish is protected by it)
Look for any ceramic fiber insulation. If you find it for kilns it will be a lot cheaper than anything designed for racecars.
Mr_Asa said:Mr_Asa said:Do you have a rough idea of square footage needed?
Im beating a dead horse here, but I ask because this is $0.38/ft^2
And it does this level of heat prevention. (Bottom foot-ish is protected by it)
Look for any ceramic fiber insulation. If you find it for kilns it will be a lot cheaper than anything designed for racecars.
firewall / engine box total area ~ 25 sq ft.
your first link is $449 for 200 sq ft, or $2.495 / sq ft
GRM is my first stop for information, i haven't searched anything on this yet. i will look for ceramic fiber / kiln insulation. thanks for the tip.
maschinenbau said:I bet the OEMs have already figured this out, perhaps luxury car firewalls or full size vans where the engine is tucked further back, so a junkyard might be a good place to check. They will probably ring it up as "carpet" which is like $15 for any amount over 3ft at my local PAP.
my local JY charges $5 for exhaust heat shields regardless of size. i grabbed a few from which i'm going to make header shields. i was looking for firewall insulation but didn't find any good donors with their engines out. probably just need to check more junkyards.
You ever make it over to this side of the lake? I have a whole bunch of super thin aluminum I got from DusterB that would be perfect for custom heat shields.
In reply to AngryCorvair (Forum Supporter) :
That was bad math. I don't even know how I did that.
Well, however I did that, the stuff works. Our head welder was playing with some of the 1/8" fiber paper we have and took an oxy/acetylene torch that he had been using to cut some 3/8" steel plate and turned the torch on the fiber which was placed on top of an empty coke can. Held it there for 20-30 seconds and nothing happened, the outside of the can wasn't even scorched
Edi: holy run on sentence. Am I doing ok? Do I need a nap or something?
In reply to RacetruckRon :
i've been in WI 5 times in the last 20 years. and 0 times in the 35 years prior to that.
I have a roll of thin "alyewminium because that's what we call it" to use as a base with air gap. Free to a good home, GR MI. Also some grade that is so hard it doesn't bend well, maybe something in between also. Trial materials for Tesla seat backs, and Leaf battery trays.
My assumption would be that at the front of the firewall you will have little airflow, so will a heat shield actually be effective. If the air is stagnant and bakes everything, it may just be hot in front of and behind the heat shield.
I would start simple and just get heat shield out of the junkyard and mount at the firewall leaving an air gap between it and the firewall.
Or you could take a cue from tve F1 and use reflective heat material on the firewall.
A crazier solution is build a yeti cup. As in put another firewall in and leave an air cap between them or foam it.
I would keep it simple and at first get the thing going and see how big of a problem it actually is. Don't want to spend 3 months on a crazy solution if it might not have been a problem anyways.
If your simple solution doesn't work and it's hard to change it, fix it with airflow.
akylekoz said:I have a roll of thin "alyewminium because that's what we call it" to use as a base with air gap. Free to a good home, GR MI. Also some grade that is so hard it doesn't bend well, maybe something in between also. Trial materials for Tesla seat backs, and Leaf battery trays.
Thanks! I'll take it if you can hold til next Fri 9/23. I'll be in GR to see Marcus King Band at GLC Live at 20 Monroe.
In reply to Opti :
I'll have good airflow while the car is in motion, as I'm building a big air duct from base of windshield to front of engine box.
DEI floor and tunnel shield
https://www.designengineering.com/floor-tunnel-shield-ii-21-x-24/
Would underhood insulation be suitable here? It seems like it would come in big pieces, and is probably much easier to salvage in a junkyard vs actual firewall insulation
Mr_Asa said:In reply to AngryCorvair (Forum Supporter) :
That was bad math. I don't even know how I did that.
Well, however I did that, the stuff works. Our head welder was playing with some of the 1/8" fiber paper we have and took an oxy/acetylene torch that he had been using to cut some 3/8" steel plate and turned the torch on the fiber which was placed on top of an empty coke can. Held it there for 20-30 seconds and nothing happened, the outside of the can wasn't even scorched
Edi: holy run on sentence. Am I doing ok? Do I need a nap or something?
Ok, I am going to get this stuff for Colin, because the exhaust is going to be a finger width from the trans tunnel/footwell and I expect it to get very, very hot.
akylekoz said:I have a roll of thin "alyewminium because that's what we call it" to use as a base with air gap. Free to a good home, GR MI. Also some grade that is so hard it doesn't bend well, maybe something in between also. Trial materials for Tesla seat backs, and Leaf battery trays.
I'll be in GR tomorrow afternoon. Is this offer still good? Will PM momentarily. Thanks!!!
i just got a vw bug with a ecotec drivetrain in the back seat. the firewall the PO built is really heavy steel so im going to remake something in alum and need to insulate it same as you.
after a couple hours of research i bought this:
https://smile.amazon.com/gp/product/B0055VTOBA/
i wish i could tell you how it works but i havent used it yet
I'd be tempted to start with Reflectix if the goal is just heat and not sound. Basically aluminized bubble wrap, so it reflects and provides an air gap. Available at Home Depot in great big rolls. Attach with tape for ducting (not duct tape). I've had good luck with Floor & Tunnel in applications where the Reflectix would probably melt, but it doesn't do as well on the $/sqft metric.
Hit up the orange or blue hardware store and buy a sheet of duct board. It's what HVAC folks use to make those square foil ducts.
Sometimes called silveRboard
Good to meet you Angry one.
Now I can say I helped with a cool project.
In reply to akylekoz :
Nice to meet you as well. And thanks for the budget-friendly material. Recap:
I loaded (6 min @ $10/hr minimum wage (really $9.47, but math), and transported (5 miles out of my way @ 20 mpg @ $4/gal, again because math) a set of tires for akylekoz, and was compensated with about 50 sq ft of thin aluminum sheet, so my budget hit will be:
(100 cents labor plus 100 cents gas)
divided by 50 sq ft material equals
4 cents per square foot.
hooray.
May I reimburse you for your trouble? Can challenge materials have a negative cost?
I won't be able to sleep at night if you lose the challenge due to a $2 budget hit.
2025 challenge second place goes to Angrycorvair! Would have been first if only that one graded fastener was in the budget.
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