what thickness for my true duals?
what thickness for my true duals? finally its time 
am getting around fabing my own duals. ive asked around for pipes prices...am going 2.5" over the axle, havent decided what mufflers am going with but def. no cats..no emission tests here so no worries.....i got prices for stainless steel, polished stainless steel and galvanized iron, but my question is what wall thickness should i go with? i found here on local shops 2.7 mm for the galvanized, 1.5 mm for the polished stainless steel and 2.5 for the stainless steel..what is best for the exhaust? thanks.
am getting around fabing my own duals. ive asked around for pipes prices...am going 2.5" over the axle, havent decided what mufflers am going with but def. no cats..no emission tests here so no worries.....i got prices for stainless steel, polished stainless steel and galvanized iron, but my question is what wall thickness should i go with? i found here on local shops 2.7 mm for the galvanized, 1.5 mm for the polished stainless steel and 2.5 for the stainless steel..what is best for the exhaust? thanks. 
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Joined: Aug 2006
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From: Hamlin ny
finally its time am getting around fabing my own duals. ive asked around for pipes prices...am going 2.5" over the axle, havent decided what mufflers am going with but def. no cats..no emission tests here so no worries.....i got prices for stainless steel, polished stainless steel and galvanized iron, but my question is what wall thickness should i go with? i found here on local shops 2.7 mm for the galvanized, 1.5 mm for the polished stainless steel and 2.5 for the stainless steel..what is best for the exhaust? thanks.
am getting around fabing my own duals. ive asked around for pipes prices...am going 2.5" over the axle, havent decided what mufflers am going with but def. no cats..no emission tests here so no worries.....i got prices for stainless steel, polished stainless steel and galvanized iron, but my question is what wall thickness should i go with? i found here on local shops 2.7 mm for the galvanized, 1.5 mm for the polished stainless steel and 2.5 for the stainless steel..what is best for the exhaust? thanks. I've never seen a discussion on thickness of the pipe so I have no idea. However, just guessing here, I'd go with 2.5mm stainless over 1.5mm polished stainless because my guess is that a thicker pipe would help hold the heat inside the pipe a little better. That's if you want to go stainless. Of course being in a place where it never rains or snows you wouldn't really need stainless because I doubt rust is much of a problem, unless you live close to the sea and have salty sea air.
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Joined: Aug 2006
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From: Hamlin ny
He's talking about the thickness of the wall of the pipe though, not the diameter of the pipe. He already knows he's doing 2.5" diameter since he wants to go over the axle.
I've never seen a discussion on thickness of the pipe so I have no idea. However, just guessing here, I'd go with 2.5mm stainless over 1.5mm polished stainless because my guess is that a thicker pipe would help hold the heat inside the pipe a little better. That's if you want to go stainless. Of course being in a place where it never rains or snows you wouldn't really need stainless because I doubt rust is much of a problem, unless you live close to the sea and have salty sea air.
I've never seen a discussion on thickness of the pipe so I have no idea. However, just guessing here, I'd go with 2.5mm stainless over 1.5mm polished stainless because my guess is that a thicker pipe would help hold the heat inside the pipe a little better. That's if you want to go stainless. Of course being in a place where it never rains or snows you wouldn't really need stainless because I doubt rust is much of a problem, unless you live close to the sea and have salty sea air.
Thickness comes into play for ease of welding and weight. Thinner stuff is marginally harder to weld to the inexperienced, but weighs quite a bit less
Heat retention mumbo jumbo is exactly that. Hear-say
Ramp up to .25" wall and talk about heat retention. Coatings do affect heat though, must like coated/painted headers. Stainless will also have a slightly different heat property than aluminized mild steel, but not enough to split hairs over
Stainless vs standard steel tubing is user preference. Stainless has a slightly different sound for a free flowing exhaust system but will never rust out
Also, Id steer clear of the shop wanting to put 2.7mm wall tubing on your car. Thats over .100" thick, way heavy stuff. Since you're talking galvanized, it seems closer to fence post tubing rather than exhaust
Heat retention mumbo jumbo is exactly that. Hear-say
Ramp up to .25" wall and talk about heat retention. Coatings do affect heat though, must like coated/painted headers. Stainless will also have a slightly different heat property than aluminized mild steel, but not enough to split hairs over
Stainless vs standard steel tubing is user preference. Stainless has a slightly different sound for a free flowing exhaust system but will never rust out
Also, Id steer clear of the shop wanting to put 2.7mm wall tubing on your car. Thats over .100" thick, way heavy stuff. Since you're talking galvanized, it seems closer to fence post tubing rather than exhaust
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Well, I had no idea what I was talking about. You however sound like you know what you're talking about so I'd listen to you and get the thinner tubing to save weight.
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TECH Enthusiast
Joined: Aug 2006
Posts: 734
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From: Hamlin ny
He's talking about the thickness of the wall of the pipe though, not the diameter of the pipe. He already knows he's doing 2.5" diameter since he wants to go over the axle.
I've never seen a discussion on thickness of the pipe so I have no idea. However, just guessing here, I'd go with 2.5mm stainless over 1.5mm polished stainless because my guess is that a thicker pipe would help hold the heat inside the pipe a little better. That's if you want to go stainless. Of course being in a place where it never rains or snows you wouldn't really need stainless because I doubt rust is much of a problem, unless you live close to the sea and have salty sea air.
I've never seen a discussion on thickness of the pipe so I have no idea. However, just guessing here, I'd go with 2.5mm stainless over 1.5mm polished stainless because my guess is that a thicker pipe would help hold the heat inside the pipe a little better. That's if you want to go stainless. Of course being in a place where it never rains or snows you wouldn't really need stainless because I doubt rust is much of a problem, unless you live close to the sea and have salty sea air.
yep am going 2.5" but the thickness vs material is my concern.
Also, Id steer clear of the shop wanting to put 2.7mm wall tubing on your car. Thats over .100" thick, way heavy stuff. Since you're talking galvanized, it seems closer to fence post tubing rather than exhaust
so what do u recommend? its true the galvanized weights a ton! and the polished stainless is too thin i think.
Buy actual exhaust tubing from a shop or other supplier. It's measured by gauge similar to wire, not actual thickness. 14, 16, 18ga are common with 16ga being what most use
Theres nothing wrong with the thin stainless as long as you weld it up alright. Id suggest against the polished tubing because its an added cost youll never see. Polish the tips where you can see it, dont bother with the rest
Theres nothing wrong with the thin stainless as long as you weld it up alright. Id suggest against the polished tubing because its an added cost youll never see. Polish the tips where you can see it, dont bother with the rest
Buy actual exhaust tubing from a shop or other supplier. It's measured by gauge similar to wire, not actual thickness. 14, 16, 18ga are common with 16ga being what most use
Theres nothing wrong with the thin stainless as long as you weld it up alright. Id suggest against the polished tubing because its an added cost youll never see. Polish the tips where you can see it, dont bother with the rest
Theres nothing wrong with the thin stainless as long as you weld it up alright. Id suggest against the polished tubing because its an added cost youll never see. Polish the tips where you can see it, dont bother with the rest