Anybody running an Aluminum exhaust?

[Mopar318]

This winter, I plan on building an aluminum exhaust system. I will shorten the downpipe I fabricated for this build, and run a hanger at the end of the stainless downpipe. Then from there it will be all aluminum. The hangers will still remain steel, but they will strap around the tubing instead of welding the hangers to the tubing which may cause cracking.

Just wondering if anyone has experience with aluminum exhaust system. Im not sure how loud it would be without a muffler, or cat, so Im wondering about that. The alluminum should absorb alot of the sound.

[contraption22]

I've only seen aluminum exhaust pipe used in very short exhausts, and not for street use. Like on drag cars that don't run very long. But give it a try! Should be a neat experiment.

[turbovanman²]

It probably wouldn't last too long as the acids and gas's in the exhaust will eat it from the inside out.

I would also think just wrapping steel hangers around the pipe will cause it too itch and wear holes or spots into the pipe. Maybe weld some ears on made out of aluminium.

[glhs0426]

Len Ayala has done it to his Neon, but the car is still being built.

I never thought about the fact the aluminum would absorb the sound! The expansion of the aluminum would worry me because I would have to run over the rear axle and there is only so much room.

[T-Bohn]

I am not sure what would be gained? Or is it one of those 'cause it's there things.

gene

[Mopar318]

I would be using 6061 which is pretty corrosion resistant. 2024 is very strong but also contains copper which will make it corrode pretty quick.

The heads on our cars are aluminum, so are the pistons. You dont see them corroding. Just have to use the right stuff.

Wieght savings, and muffling capabilities. A full 3" stainless steel exhaust weighs a ---- ton, add the mufflers to that too. There was a pictures floating around of a 4" exhaust made for a honda civic out of alluminum with a little girl holding it over her head.

[Mopar318]

http://i48.photobucket.com/albums/f224/cwestinek/IMG_5360.jpg

[turbovanman²]

I would be using 6061 which is pretty corrosion resistant. 2024 is very strong but also contains copper which will make it corrode pretty quick.

The heads on our cars are aluminum, so are the pistons. You dont see them corroding. Just have to use the right stuff.

Wieght savings, and muffling capabilities. A full 3" stainless steel exhaust weighs a ---- ton, add the mufflers to that too. There was a pictures floating around of a 4" exhaust made for a honda civic out of alluminum with a little girl holding it over her head.

Heads and pistons are but they don't get hit with the full effect of the gas's so to speak. Exhaust almost always rusts from the dp back, :(

It should be a neat project, that's for sure.

[Mopar318]

Heads and pistons are but they don't get hit with the full effect of the gas's so to speak. Exhaust almost always rusts from the dp back, :(

It should be a neat project, that's for sure.

If I remeber your ride superbikes right? Every take a look at the contruction of alot of the race bikes? You will find aluminum on the mufflers on those.:)

[BadAssPerformance]

Depends on the temps.. I made a WG gasket out of aluminum and it melted it enough it blew out in liquid form :eek:

I have thought about AL for weight, but decided to just go thin wall 304 for the straight sections.

[turbovanman²]

If I remeber your ride superbikes right? Every take a look at the contruction of alot of the race bikes? You will find aluminum on the mufflers on those.:)

I've honestly never seen any in aluminium, just lots of stainless and titanium.

[Mopar318]

Depends on the temps.. I made a WG gasket out of aluminum and it melted it enough it blew out in liquid form :eek:

I have thought about AL for weight, but decided to just go thin wall 304 for the straight sections.

I think you would agree the temps at the wastgate are alot hotter than the temps on an exhaust from behind the downpipe. What grade of alluminum did you make the gasket from?

[BadAssPerformance]

Yes, but the heat after the turbo is pretty fricken hot too. What temp does steel glow red at?

6061... dont remember if T4 or T6 HT

Are you looking for weight savings? thats the only real benefit...

[Mopar318]

Yes, but the heat after the turbo is pretty fricken hot too. What temp does steel glow red at?

6061... dont remember if T4 or T6 HT

Are you looking for weight savings? thats the only real benefit...

Yeah, weight savings, and just something different. I have been seeing turbo cars even use aluminum for downpipes...thought maybe I would try it.

[Mopar318]

http://img291.imageshack.us/img291/5063/june2009007.jpg

[BadAssPerformance]

Free flowing, large diameter, big smooth radii could work. The problem would be a hot small radius bend 90° corner out of small diameter...

[minigts]

I was checking temps under the car when my car seemed to be running hot. At the cat, they were about 300-350. After the cat they went down significantly. I'd say that at a certain point, aluminum should be fine, maybe after the downpipe?

[turbovanman²]

http://img291.imageshack.us/img291/5063/june2009007.jpg

I bet he's running methanol, which runs alot cooler. Its a cool project but I bet you'll melt it.

[Force Fed Mopar]

http://img291.imageshack.us/img291/5063/june2009007.jpg

Looks to me like there is a short piece of steel coming off the turbo, maybe 6" long, before the aluminum starts.

[T-Bohn]

Ok!!

now that sounds like a cool idea!!!! light ( always better ) and resonate at a different tone. neat idea and like i said at the start....because you can


Geez can you imagine how strong that little girl is gonna be when she hits her teens!!

Playground = watch out boys

gene

[trbowgn]

You said you were going to leave your downpipe steal so I think it could work.
Sounds like you have researched what material to use so go for it. I don't think it will melt if you are not right after ther Turbo. As far as corosion goes I am not sure but I don't think you are building a daily driver so useage will be limited.

[turbovanman²]

Looks to me like there is a short piece of steel coming off the turbo, maybe 6" long, before the aluminum starts.

Its still aluminium, you can't weld steel to al unless things have changed, ;)

[Mario]

You could use a bimetallic strip to join the two, no?

[Mopar318]

Looks to me like there is a short piece of steel coming off the turbo, maybe 6" long, before the aluminum starts.

That looks ceramic coated. You cant weld Aluminum to steel.

Bimetalic strip? Never heard of this in welding?

[Mopar318]

Does any gody have an EGT gauge? Or how about a thermo in the downpipe? If so what temps are you seeing.

[Ondonti]

He already said he was going to use it after the steel downpipe. READ before posting advice.

Everyone around here is getting aluminum exhaust. I looked into it at the end of last year but decided I couldnt afford it at the time.

I am actually more interested in running a cutout before it goes to aluminum, then only run 2" or so aluminum out to the back. That way you could have a full quiet light exhaust (about 5 pounds ish), and still have full flow. My exhaust after the downpipe is about 50-60 pounds with muffler.

[turbovanman²]

He already said he was going to use it after the steel downpipe. READ before posting advice.

Everyone around here is getting aluminum exhaust. I looked into it at the end of last year but decided I couldnt afford it at the time.

Yes, he did, I saw that, but unless he has a long DP, I think it will melt.

I would assume the temps in the DP would be about 2-300 deg less than at the turbine housing.

[Ondonti]

Okay, example. I have a couple friends with billion hp 2jz street daily drivers with 4" aluminum exhaust.

I've never heard of one failing on a well built car.
maybe we should just tell him in classic td/tm mentality, "stock is better/faster, duh!"

[turbovanman²]

Okay, example. I have a couple friends with billion hp 2jz street daily drivers with 4" aluminum exhaust.

I've never heard of one failing on a well built car.

See, there we go, solid info, :thumb:

Are they running it right off the turbo or ?

[Mopar318]

Okay, example. I have a couple friends with billion hp 2jz street daily drivers with 4" aluminum exhaust.

I've never heard of one failing on a well built car.
maybe we should just tell him in classic td/tm mentality, "stock is better/faster, duh!"

How loud is the car? I know its hard to compare different engines, but I would think the aluminum should material itself should muffle alot of the sound. Dont worry about the "classic TD metalitiy" if thats what it is, then I never got to that point. I fabricated almost every part for this car...

The point is, Im wanting to run a full exhaust, but dont want an extra 60 pounds like you said, and adding that to an already heavy car.

[Ondonti]

steel downpipes, flange, then aluminum exhaust..sorta like an aluminum catback even though you probably don't have a cat.

I can only conjecture about the sound issue...people seem to claim the idea but I don't know about it in practice. 4" exhaust is gonna be fairly loud and lack of muffler....I wonder more about what in cab resonance would be on a gutted interior. Thats what gets annoying.

[2.216VTurbo]

Anyone that went to SDAC 19 saw a car with an Aluminum exhaust AND an Aluminum downpipe:thumb: True, it is a drag car but it had made many passes on the set up and I couldn't see any damage from the outside of the pipes anyway;) Name that car anyone??

[rx2mazda]

B.Slowe

9sec car.....aluminum DP.
http://i93.photobucket.com/albums/l71/rx2mazda/DSC00393.jpg

[Ondonti]

It might be a bad idea for those who go WOT for a few minutes but those guys don't last long.

[mopar-tech]

For the record- Cat converters don't start working till they hit 600F and can run as high as 1200F.

There some facts for ya.

[turbovanman²]

For the record- Cat converters don't start working till they hit 600F and can run as high as 1200F.

There some facts for ya.

Or higher if you have a misfire or 2, :lol:

I just thought of a good test for the pipe you want to use, get a cutting torch and try to melt the one you want to use? Not sure what the temp of the flame is but I think that would be a good test. I know in the past, I've played with acetylene torch's and aluminium and its fun to make it puddle, :eyebrows:

[t3rse]

which will also cut mild steel....like that used in your exhaust....

[turbovanman²]

which will also cut mild steel....like that used in your exhaust....

I didn't say to use the cutting portion, :confused:

[t3rse]

get a cutting torch and try to melt the one you want to use?

:confused2:

[puppet]

How well will the AL hold up under stress? ... at elevated temps? ANSI codes don't allow its use over 400*F in certain applications.

What will the corrosive exhaust gas do to it over time?

Why not just use 20ga. SS?

[Ondonti]

build a 4" exhaust that weighs 11 pounds out of ss and I will get interested ;)

[BadAssPerformance]

build a 4" exhaust that weighs 11 pounds out of ss and I will get interested ;)

Hard to beat the weight of aluminum without getting real expensive...

I'm guessing Ondonti's 'team j-yard' 3.0L has the lightest exhaust available... Invisible! :clap:

[puppet]

Pretty sure 20gaSS weighs less than the AL ga. tubing you'd need to be strong enough. Might even be cheaper. Got it beat hands down in all other areas, too. (corrosion, heat, stress)

[crug75hid]

Thanks for the nice info.

[22shelby]

i say "give-er" id just heat shield around the gas tank, if u got the matierial then do it if it works great if it dont then back to the drawing board. just make sure u post back up w/ results to inform us of the "test"

[Mopar318]

I have never seen 20 gauge stainless still in 3" mandrel bend form. If its out there please let me know where to get it.:confused:

[puppet]

I have never seen 20 gauge stainless still in 3" mandrel bend form. If its out there please let me know where to get it.:confused:
http://www.spdexhaust.com/index.html

[cordes]

I double checked the elephant memory to be sure, but the melting point of Al is 1220.666 °F. He should be fine if he runs the stock DP from a melting aspect.

[turbovanman²]

http://www.spdexhaust.com/index.html

DOH!!!

Funny, you guys are going for light, I am slowly replacing my exhaust with thickwalled 10 gauge stainless, have half done, :nod: Looks nice and holds up better, already blown out 2 tailpipes, :(

[Mopar318]

I double checked the elephant memory to be sure, but the melting point of Al is 1220.666 °F. He should be fine if he runs the stock DP from a melting aspect.

Well I built a custom stainless for my setup, but I know what you mean. I checked the temperature of my down pipe after a full throttle run and it came to 425 degrees. now Im sure it cooled down a few hundred degrees since it was 15 second or so from checking it but I know it wasnt anywhere near 1200 degrees. Having a cat in the system will really make everything run hot, and I plan on removing that also.

[8valves]

I know I'm late to this, but it'll be fine. Run SS for the initial 12" of DP or so off the turbo then go to a V band connection, one SS one AL, and AL from there. No problems. We did AL exhaust on Lee's silver car and it's the best thing ever. The exhaust is totally cool to touch about 15 minutes after it was running. Great to work around. Plus, I love welding AL. :)

[88shadowpjct]

i know this is different, but on my 05 wrangler 4.0L i had to make an exhaust. couldnt hook a tailpipe up to it and had to drive it for a while. took a piece of ebay 2.5" IC piping i had laying around and band clamped it after the rear cat (high flow magnaflow 2.5") to dump out the side. had it on there prob 3 weeks or so, sounded different than a steel piece in the same spot, when i took it off to hook up a tailpipe, i took off the clamp and suprisingly the aluminum slid right out. i thought it'd corrode together. i realize its not as hot as the turbo exhaust, but as far as im concerned, an aluminum exhaust would be sweet as long as there's a steel DP to take the abuse straight off the turbo. esp if you use good aluminum.

[Mopar318]

I know I'm late to this, but it'll be fine. Run SS for the initial 12" of DP or so off the turbo then go to a V band connection, one SS one AL, and AL from there. No problems. We did AL exhaust on Lee's silver car and it's the best thing ever. The exhaust is totally cool to touch about 15 minutes after it was running. Great to work around. Plus, I love welding AL. :)

Your not late yet, I havnt even started on this, but I hope to do it this winter. Measured the temps right at the downpipe after the turbo and I get almost 600 degrees after a full throttle run. I would say less than 1000 degrees during the actuall run. Down 3 feet I should be more than safe.