i could lose ten pounds off my ass a hell of a lot cheaper than i could lose ten pounds off my engine.

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I've been calling it as i see it for my entire life and that's not about to change. Take it or leave it.

Couldn't we all? Well, most.... Ok, many...

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David Kight
'62 Valiant Signet, White
'98 Dodge Dakota
'06 Jeep Liberty

Growing older is unavoidable but growing up is strictly optional.

Yeah, but removing 10 pounds from my slant is a lot EASIER than losing 10 pounds off my a$$...

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vm

As noted by others Aluminum doesn't do well with heat. You begin to partly anneal it at temperatures above around 125 C. Unlike a cylinder head the exhaust manifold gets no cooling (nor would you want to cool it I suppose). I would imagine an AL exhaust would function for a short while, then it would get saggy and start to leak. Ti perhaps would work--of course it would cost a mint. It is with a heavy (pun intended) sigh I say that regular cast iron seems to be the cheap and bulletproof material for exhaust manifolds. My experience with steel headers has been one where I just put the cast iron pigs back on my rig... At least AL would be light and easy to handle, but they wouldn't last long...

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Slanted D150

We have a Titanium processing plant down south of us... when that stuff gets hot enough or you weld or grind on it... it gets kind of 'funny'... I really love the sparks that crackle and explode... it makes me like aluminum, stainless, and iron... much more....

Too bad the government would make us register the pipes since they would be of a 'sizeable' quantity... (like some terrorist would grab our headers to make a rocket casing...riiiight!)




-D.Idiot

I can't say I've ever heard of the company "registering" titanium. It's not plutonium. I could get the material in a day if the funds were available, from legitimate sources.

I have seen titanium burn, it's really a manufacturing issue, it would not be a problem in an exhaust. The temps are not even close.

I was joking anyway. It would cost a fortune. A decent set of manifolds / headers out of 304 stainless would be a bit more realistic, but you could still build a whole engine for less.

Yep, another company my buddy works for buys sheets of it for 'specialty' work (golf club heads, etc...)... they have to fill out a form on how much they purchased, what they are using it for, and then have to weigh the scrap and let them know how much they are shipping back to the processing plant for recycling... where it gets weighed again and more paperwork filed...

-D.Idiot

D.I., is'nt that called inventory?? I worked in a trailer shop and we also had to weight our scrap from each project.

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Chris'
Autobody
Restoration
Service

Strength & materials Department:

http://wiki.answers.com/Q/What_is_the_m ... f_aluminum

This is the temperature that aluminum turns to liquid. Before this melting point, aluminum enters a "Plastic State", as do most other metals.

Let me illustrate by using the "Sugar Daddy" analogy. After one has been sucking on a solid Suggar Daddy candy for awhile, one will at some point bite down on it, and while it is clamped tightly by the teeth the candy is pulled producing long strings of the candy. When the hard candy begins to stretch this is the point of plasticity. A point when all strength is lost.

Plasticity can be arrived at two ways, one by applying a tensile load to failure as the Suggar Daddy example demonstrates, the other by heat.

Some metals have a larger plasticity temperature range than others, steel being one. Aluminum dose not fit this description, it becomes plastic, than melts at 1220 deg. F. in a narrow temp. band.

So to sum this up, aluminum dose not lend its self to internal combustion engine exhaust manifold temperatures.

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67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC

In your case you don't send your inventory reports to a government agency, and don't have to have inspections on your 'scrap pile' and 'access'... oddly they didn't blink when my buddy used a couple of 4"x4" pieces to make some sheetmetal 'quickie' scribes pout of the scrap...


-D.Idiot