View Full Version : EMT for exhaust


Scott
01-16-2006, 10:41 AM
Aside frome the galvanizing what is the difference between emt and automotive exhaust tubing and who has used it?

Ragtop
01-16-2006, 10:44 AM
I used it on a VW dunebuggy when I was a kid. Worked Ok, but I think exhaust tubing is usually a little heavier wall.

C9
01-16-2006, 11:43 AM
I'm not too wild about welding galvanized anything.

Aluminized exhaust tubing doesn't seem to have a fume problem like galvanized does.

Seems like it lasts for quite a while too.

Sinner
01-16-2006, 11:53 AM
The diameters are a little different, but it does work.

JohnnyFast
01-16-2006, 12:07 PM
Also, EMT has different dimensions than exhaust tubing which is measured on the O.D. (1 1/2" tubing is 1 1/2" O.D.) whereas EMT's dimensions are nominal only and they do not measure the same as they are called out. See this chart :

http://www.vogeltool.com/conduit.html

U-bends for tubing won't be the same O.D. as EMT with the same size designation. And muffler shops wouldn't have dies in the correct size to bend EMT.

fur biscuit
01-16-2006, 12:17 PM
built headers for a model T speedster out of it once. The low exhaust temp didn't seem to cause it any problems in terms of burn through or warpage.

NoBackPressure
01-16-2006, 12:21 PM
Aside frome the galvanizing what is the difference between emt and automotive exhaust tubing and who has used it?

Hello,

All 3 of my cars have 2" EMT conduit. Got from Home-Depot in 10' lengths for cheap. I have one of those cheap pipe benders and with a little heat, bends nicely. I weld all the connections so I don't have to worry about slip fits and such. I think it works great if you like to fab your own exhaust up cheap. The pipes have held up exceptionally well over time too. Make sure you wire brush and paint the welds (rustoleum aluminum or black grill paint).

By the way, 1-1/2" EMT works perfect for Harley exhaust too...
Good luck.........

Scott
01-16-2006, 05:57 PM
May give it a try, Ive been bending emt for 22 years. I can bend up to 1-1/4, which is 1-1/2 OD with a hand bender. Anything bigger and you need a mechanical bender. Of course you can by prefabbed bends in many degrees of bend.
That being said I could get the same result using regular exhaust tubing.
Thanks for the input guys

Tman
01-16-2006, 06:01 PM
May give it a try, Ive been bending emt for 22 years. I can bend up to 1-1/4, which is 1-1/2 OD with a hand bender. Anything bigger and you need a mechanical bender. Of course you can by prefabbed bends in many degrees of bend.
That being said I could get the same result using regular exhaust tubing.
Thanks for the input guys

try it, a pal fabbed up lakes headers and exhaust out of it (he teaches electrical at a Votech) then he sent it out and has it ceramic coated, It has held up great over 5 years.

May Pop
01-16-2006, 06:24 PM
Works great. welds good with o/a and fresh air. Different brands are coated differently. Plenty of adapters out there to use std. mufflers too. Talk to an electrian most will give you some scraps to practice on.

Nads
01-16-2006, 06:26 PM
I did my '34 Ford with the stuff a few years ago, it's holding up good but it's nasty shit.
Even if you grind the galvanizing from the outside, it's still in the inside.
Drink a lot of milk after you weld the shit.

oil*can*harry
01-16-2006, 06:59 PM
Is it galvanized or is it Cadmium plated?

Stevie G
01-16-2006, 08:00 PM
Is it galvanized or is it Cadmium plated?

Picky about which poison kills you??:rolleyes:

Kevin Lee
01-16-2006, 08:06 PM
The open exhaust on my roadster is EMT and has worked great. With some careful planning I found everything I needed to make it fit pre-bent.

james
01-16-2006, 10:35 PM
Nads, didn't you get real sick when you did yours?

Scott
01-16-2006, 10:55 PM
What will take the gal off of the inside, hone.wire brush or a chemical like muriatic acid?

stealthcruiser
01-17-2006, 07:23 PM
What will take the gal off of the inside, hone.wire brush or a chemical like muriatic acid?


try some vinegar,and don't rush it.
I knew some guys who did A/C ductwork for a living,
and when they had to weld some pieces,they
treated the weld area with vinegar prior to welding.

I never saw any of the white zinc "floaters" in the air
when they welded.

tommy
01-17-2006, 08:40 PM
I don't get it??? If you work construction and you get it for free that's one thing, but if you have to buy it, I think it's a waste of money. Real aluminized exhaust tubing that is made for bending isn't that expensive. What are you going to save in materials??? 10 bucks? Yes I've welded my share of galvanized pipe and it takes some time to get rid of the taste. It just ain't worth it!

One nice thing about aluminized tubing...you can make it look real good with a scotch brite pad in just a few minutes time. Use the right materials. MHO

soldermonkey
01-17-2006, 10:14 PM
I wouldn't mess with that crap, a friend welded galvanized pipe several days in a row and was outside, he is new graveyard friggin dead. He didnt die gracefully either, took several weeks to slowly sign off.
Nasty stuff.
My $.02

dave

rustypipes
01-18-2006, 12:04 PM
Seriously Welding that stuff is fatal, no joke. Dont try it. It aint worth it