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Posted by: obscurity Jul 24 2011, 09:57 AM

I am in the process of doing a fair amount or metal replacement including the longs and the cross member. I would like to close up the long before I remove the cross member but I don't want to weld the cross member to the long with the paper tube inplace and risk catching it on fire. Is there a non-flamable replacement that works as well as the original paper ones?

John

Posted by: TargaToy Jul 24 2011, 02:51 PM

I welded my new long cover on with no issues--at least if the heater tube WAS turning to cinders inside, I was unaware

What I made sure to do was keep the holes I drilled for the plug welds nice and centered on the flange so that they were snug against the surface of the long with less chance for something molten to drip inside. And if they were out a little, I tapped them snug with a drift individually before each weld.

Posted by: kg6dxn Jul 24 2011, 02:54 PM

A VW type 1Bug exhaust heat intake tube is the same diameter. It works on the freash air box too. Any Bug shop should have them. The 914 ones are paper wrapped foil. The VW version is only foil.

Posted by: Ian Stott Jul 24 2011, 06:03 PM

If you are close to an airport go to the maintanance shop where they work on small aircraft like Cessna's, they have great high heat tubing which works great for us and they will have different sizes, if not they can get it very quickly.

Ian Stott
Moncton
Canada

Posted by: john rogers Jul 24 2011, 06:29 PM

Both our 1973 and 1974 did not have a tube of any sort in the logitudinals. As long as the box are has no holes from rust or anything, nothing should be needed as air goes in the back and comes out the front just fine. The 1974 heating could melt you in the winter, of course we are in San Diego so we don't have real winters??!!

Posted by: obscurity Jul 24 2011, 07:34 PM

QUOTE(john rogers @ Jul 24 2011, 08:29 PM)

Posted by: kg6dxn Jul 24 2011, 07:39 PM

Air will flow if removed but at a slower pace due to fluid dynamics. Moving air is considered a fluid. The parasidic drag caused by the turbulance will reduce the efficiency of your heater. It may still be acceptible if it doesn't get too cold where you are.

Posted by: john rogers Jul 25 2011, 10:27 AM

The post about turbulence and parasitic drag in the longs might be true but remember that without the tube, the cross section where the air is flowing is larger so there is less resistance which would probably offset any buffeting from any metal obstructions inside. When I looked inside the right long getting ready to run oil lines, there was nothing in there, smooth as can be? But that might also be negated if you drive fast enough so that your car is moving faster than the air inside the longs then the air might flow into the windshield vents and back to the engine. At any rate good luck.

Posted by: rdauenhauer Jul 25 2011, 12:25 PM

The heat tubes mentioned are more than just simple expanding foilized paper.
in each long they are a pair of those type tubes of differing diamieter one inside the other with fiberglass wrapped around the inside one then two plastic caps glued at each end with the inlet/outlets necked down to the dia. of the inside tube.
they are slip fit over the steel J tubes the protrude from the long and held in place by spring type brackets riveted to the long.