Intercooler piping solutions

[mullett]

A post earlier sparked my curiosity about DIY cooler piping. Just thought I'd list a few ideas and the pros/cons I can think of, if anyone's tried these or can think of a reason why they would/wouldn't work, post away! (listed from cheapest to most $$$ and DIY simplicity...I think)

PVC pipe: Cheap, brittle, held together with glue. Easy to DIY, no tools needed, just some time.

Rubber hosing: if you can find enough bends, all you'll need is some straight pipe (cheap) and a lot of hoseclamps.
Pros: Easy to make and flexible enough that you don't need to be really accurate. Cheap (if you've got some bends), and no special tools needed.
Cons: Lots of hoseclamps to worry about blowing off, lots of flex (might not be a problem) not very neat.

Copper tubing: Don't know much about this...but I'm curious.
Pros: Should be easy to come by, maybe not in the larger sizes. Easy to weld with a gas torch and some flux, joint is strong if it's done right. Easy to get a good seal.
Cons: Not as strong as stainless/aluminium. Not as shiny either

Mild steel exhaust tubing: 1.6mm mild steel, exhaust tube.
Pros: Cheap and available, can be brazed or welded to join. Strong.
Cons: *can* rust, heaps of debate about if this is really a problem. Will need good hacksaw skills or a drop saw to cut neatly, and a oxy welder/MIG/TIG/stick welder.

Aluminium tubing: Light, strong and not too hard to work with if you've got the tools.
Pros: Light, strong and not (very) prone to corrosion. Pretty (if that's your thing) Transfers heat quickly.
Cons: Expensive to get someone else to fabricate, will need VERY good gas welding skills or a TIG to weld, but easier to cut and smooth the faces than mild steel.

Stainless tubing: Similar cost to Aluminium, same fabrication difficulties as Mild steel, and more.
Pros: Strong, not easily prone to corrosion, holds a finish very well.
Cons: Expensive, very difficult to weld well with anything other than a TIG. Can be MIG or gas welded, but is ugly and difficult unless you're VERY good.

Suggestions? I'm particuarlly curious about copper tubing.

RM.

[thechuckster]

another DIY is to assemble frankenstien piping from all the bits of EFI intake piping you find at wreckers.

Not ideal for high levels of boost but you get flexible and concertina bends and any solid plastic stuff has beads at either end to prevent flexible hoses slipping off.

[Mos]

PVC pipe: Cheap, brittle, held together with glue. Easy to DIY, no tools needed, just some time.

Bad idea. Softens easily with heat. 90 or so degrees makes it so soft that hose clamps on hoses will deform it to the point where it will fall out of the hoses. Might be fine for cold climates and mild use, but forget it in "normal" use (The "glue" is actually a catalyst that causes the two surfaces to fuse together - not sure exactly on the process but it's not a glue per se).

Copper tubing: Don't know much about this...but I'm curious.
Pros: Should be easy to come by, maybe not in the larger sizes. Easy to weld with a gas torch and some flux, joint is strong if it's done right. Easy to get a good seal.
Cons: Not as strong as stainless/aluminium. Not as shiny either
Suggestions? I'm particuarlly curious about copper tubing.

Copper is far from cheap, and lately has become dearer. I've never even looked at copper tubing of the required diameter for cooler plumbing but if I have to take a stab I'd say it's a lot more expensive than alum or SS. Have you priced it?

Aluminium tubing: Light, strong and not too hard to work with if you've got the tools.
Pros: Light, strong and not (very) prone to corrosion. Pretty (if that's your thing) Transfers heat quickly.
Cons: Expensive to get someone else to fabricate, will need VERY good gas welding skills or a TIG to weld, but easier to cut and smooth the faces than mild steel.

Alum isn't that good for corrosion resistance when subjected to constant moisture where the oxide layer is affected.

Stainless tubing: Similar cost to Aluminium, same fabrication difficulties as Mild steel, and more.
Pros: Strong, not easily prone to corrosion, holds a finish very well.
Cons: Expensive, very difficult to weld well with anything other than a TIG. Can be MIG or gas welded, but is ugly and difficult unless you're VERY good.

This is the only material cooler plumbing should be made of (Yes, it's a stir )

Mos.

[merc-blue]

What about painted mild steel? if you were to pain internaly (as best you can) and externaly with a heat proof paint would mild steel be THAT bad with rust?

[mullett]

I've heard it said quite a few times that mild steel will rarely rust as intake piping, even un-painted. Maybe make your pipes and get them Zinc Plated?

RM.

[merc-blue]

thats going to cost me more than just getting stainless?

[thechuckster]

you could also get mild-steel piping HPC coated - that would eliminate the rusting issue plus you'd have a great choice of colours and finishes.

[jzk25]

Stainless steel tube is very expensive if you buy it from a retail outlet like exhaust shops. They must mark it up about 150%. Look in the yellow pages for stainless steel suppliers and approach them directly. I use Tubesales in Stapylton Qld.

Stainless is always the winner IMO. A MIG should never be used for intercooler piping, it leaves too much rubbish inside the pipe. A TIG on the other hand gives a perfect finish instantly and leaves next to nothing in the pipe. An Inverter TIG can be had for under $1000 now, this is all you need for any ferrous metal. Ally on the other hand requires an AC TIG that costs about $5k for a known brand and also requires a much greater level of skill to operate.
I want to get an AC tig when funds allow but the inverter I have is excellent, best thing I ever bought.

[boxh34d]

Another negetive for the copper is that it's surface corrorion is quite powdery, and brittle, and this is not what you want in your intake plumbing.
The other thing is that in the kind of sizes we are talking, it is very expensive, and bends are almost impossible to get. I don't know whether they make softened copper that big, so bending may not be an option.

[Mos]

I've heard it said quite a few times that mild steel will rarely rust as intake piping, even un-painted.

I had a 90 degree 2.5" mild steel bend on the sprinter for 7 years without any corrosion prevention measures. The only part that had surface rust was the exposed portion between the hoses - the part under the hoses had no corrosion, as neither did the entire internal surface.

I live reasonably far from the ocean - in coastal areas even stainless corrodes, so things like that would be more critical.

Mos.

[reecegze]

I am an refrigeration mechanic and can get many length of copper really cheap usually 120$ a length and you can only by in 6metre lengths , my fmic is going to consist of 2 1/8 piping with 90 degree bend and 45 degree bends it practicually gonna cost me nothing to fabricate it. I am going to use insul paint to stop the heat generating through the copper and use bradffex "insulation" to insulate the piping completly.

ill let you know how it goes

[poorolla]

Okay i decided i had to get in on this one...

Firstly, one con not mentioned for aluminium cooler piping is that it can easily crush near the ends when people use those HUGE clamps people tend to use these days, and its very difficult to tell how tight you are doing it up when your turning a 10 - 12mm screw Not a common problem but one worth being aware of anyway..

My experience with mild steel intercooler piping has been very positive.. You need only paint the outside of the piping (properly with half decent paint) and before installing each bit of pipe spray a little WD40 or similiar in the pipe and use a rag through the pipe to spread it around.. After the initial install, there is always going to be *some* (it doesn't need to be much at all) oil from the turbo to leave the walls coated enough to prevent corrosion.
My car, and countless cars of friends and foes i know have used mild steel without a hassle. Sure, Stainless looks really nice when its all polished up, but for the price you pay it is often smarter to go with mild steel.
One thing that needs to be cleared up is that internal rust on mild steel cooler piping would propagate very very slowly. I don't know anyone with a turbo car that doesn't take a section of cooler piping off from time to time for whatever reason so it is easy to keep an eye on the condition of your piping. You would have to leave a car for years for anything to corrode enough to find bits flying into your engine!
I have never painted the inside of any cooler piping, but i would actually be more afraid of the paint flaking and entering my engine than any rust
Just my opinion, but for those on a budget, dont be afraid of using mild steel..

Cheers,
Poo.

[mullett]

I agree with you about not using a MIG, for sure. On the plus side, you can braze many materials very easily with a gas torch, and get a similar finish (or weld filler-rod free, if you get your cuts right). I've heard stainless is pretty hard to gas weld though...A TIG is on the cards, for sure, but not for a while....

RM.

Stainless steel tube is very expensive if you buy it from a retail outlet like exhaust shops. They must mark it up about 150%. Look in the yellow pages for stainless steel suppliers and approach them directly. I use Tubesales in Stapylton Qld.

Stainless is always the winner IMO. A MIG should never be used for intercooler piping, it leaves too much rubbish inside the pipe. A TIG on the other hand gives a perfect finish instantly and leaves next to nothing in the pipe. An Inverter TIG can be had for under $1000 now, this is all you need for any ferrous metal. Ally on the other hand requires an AC TIG that costs about $5k for a known brand and also requires a much greater level of skill to operate.
I want to get an AC tig when funds allow but the inverter I have is excellent, best thing I ever bought.

[JustCallMeOrlando]

PVC can work well. I won't argue with the results of Matty's car. It's held up to his driving and Perth's summers, so although it's bad in a theoretical sense, it appears to be holding up well. Would I do it though? No.

I had mine done in stainless steel. In retrospect, I probably would've got it done in mild steel, painted the pre-cooler side and had the post-cooler side HPC coated. I live a few km's from the ocean, I started getting a little bit of corrosion on the outside of my IC piping which made it look crappy, so I ended up spraying it black when I fixed my BHG.

[Classique71]

HPC coated mild steel/stainless steel combination for the win

The pipes in theory should outlast the car



PS yes its an untidy engine bay! But it works very very well