The Stovebolt Site Forums The Shop Area General Truck Talk Engine Heat in Cab

I did a quick search and didn't see anything on the subject of engine heat in the cab.
My truck engine seems to put a lot of heat into the cab. My a/c unit tries to fight it, but it is, in my opinion, losing the battle badly. I have about two layers of the bubble stuff covered in aluminum foil on each side on the fire wall, plus a thin layer of batted insulation. All the holes are plugged, but the problem is bad. It almost seems like there is a hole in the firewall that it is coming through, but there is no hole. Before the 261, the 216 wasn't quite as bad. That makes sense to me, since the 261 is a bigger engine, but I don't know what to do with it or what might be may be the real good stuff to use.
Thanks for any help!

how thick is the insulation? Is your heater core shut off?

Joe...I had a similar issue in my '42 1/2t. I felt heat when I drove the truck, even with the windshield cranked open. What was preplexing is that my firewall was not warm/hot to the touch...by process of elimination we found that the heat was coming up through the openings in the floor from the exhaust system. I insulated the floor and for the most part solved the problem.

My friend had the same problem.....

A 53 1/2 ton with a V8...It was awful. Turned out he was getting a load of heat sink from the exhausts.
He spent a bit more time (and money) on good insulation on the whole floor including under the seat and the firewall.
Making sure there were no openings or gaps.

It made a big difference,mind you we don't have to deal with the same kind of ambient air temps you guys are dealing with.
It could be you're getting quite a bit of radiated heat through the roof as well.

Ahhh. Engine heat.
I wrapped my headers with lagging. In fact, I used 60 feet of lagging just on the headers for the 216. I also wrapped my exhaust all the way back, as I am a spaz. I am ready for the salt flats!

It has made a noticeable difference in the underhood temperature. I guess it must be cooler in the truck as well, but I drive with the windows open, and the side, and cowl vent as well. Plus, I don't live in texas.

I have the stock firewall pad, and a heavy felt pad and rubber mat on the floor.
I don't know if that helped at all.

If you do wrap the headers/exhaust, the best tip I can pass along, is to soak your lagging in a bucket of water before you wrap it on. Plus, when you start 'er up you get the feeling you are in a Stanley Steamer.

I think you need to explain this "lagging" MrLang - exactly what did you use that withstands exhaust temps? doubt there's many steam fitters here

Bill

Probably means this stuff.

There is no heater in my truck. I have never had one. The exhaust is a possibility. I just had new aluminum head pipes put on the truck. The insulation is a total of about one inch thick on the firewall. I may need to beef that up, but I'm going to look at the floor,also.
The truth is, the firewall insulation never seemed to make any difference. I have the doors and cab sealed up pretty well and is it seems better - definitely quiter!
There has to be a product that will keep that heat turned back - I just got to find it.
Thanks for the suggestions, everyone!

Here's a pic of the lagging.

http://i221.photobucket.com/albums/dd45/HomeCrafter/IMG00212.jpg

Nowadays, its made of woven fiberglass. The discoloration was caused by the VHT paint underneath burning off. Supposed to be good for 1500 degrees. Guess it gets hotter under the lagging than I thought. With the "mummy" conversion, I can drive on the highway for an hour, stop, and put my hands right on the headers. For that matter, the pipe all the way back, as it is wrapped as well.

This might work,
http://www.lizardskin.com/pages/ceramic.php

Joe

Generally speaking, the coatings make the pipes look pretty, but don't hold the heat back as much. Fiberglass lagging is as effective as asbestos.
Do a search, there is a land racing forum, lots of discussion over there about this stuff. Enclosed streamliners have these problems all the time.

Thanks Bill, I forgot to mention this stuff as well.
As an added benefit,it can also improve performance too.

I have the same problem in my 37 and I just have carpet glued on the firewall,opening the cowl vent usually gets rid of the problem when its hot and keeping it closed when its cool gives me heat since I have not installed the heater.

Found this stuff from DEI (not the NASCAR company). I haven't tried it yet, still too far away on my bolt for details like this, but I have an uncle who uses it on his '69 Camaro and swears by it. More pricey then JEG'S, but for some that doesn't matter.

http://www.designengineering.com/products.asp?m=sc&cid=3

When my dad originally rebuilt my '51 he installed a shut off valve on the heater hose so that there was no residual heat given off by the heater core. Closed it in the summer, opened it in the winter.

Try driving a COE. It can be 45F outside and its all you can do not to sweat, with the windows and winshield cranked open.

I believe that!