Turbo Piping - Pre-Cooler

Desert Sasqwatch

Goblin Guru
Not sure how to open a discussion on this topic as it is more of a question than anything. Does someone who has a lathe and a mill (or access) think it is possible to make a custom turbo pipe? It would look like the attached pic, but would be longer than the 9 inch pipe that is currently available from the manufacturer (he won't make it longer, I asked). It would start with 3.5 OD x 2.5 ID aluminum pipe, finished length 14 inches. If you think this is a doable challenge, let me know. I'm trying to determine if this a worthwhile idea. Thanks.

19968
 

Ross

Goblin Guru
Buy 2 of them, and Tig weld them together? It would have a 1" break in the fins in the middle.
How expensive is the 9" length?
 

Desert Sasqwatch

Goblin Guru
Buy 2 of them, and Tig weld them together? It would have a 1" break in the fins in the middle.
How expensive is the 9" length?
Roughly $50 each.
Good idea, but two welded together would be too long and still require some machining to modify to the 14 inch length I require. Thanks.
 

Peregrinus

Well-Known Member
Honestly I'd go for what he said, buy 2, cut the needed length off both and weld them in the middle with your desired overall length of 14", probably going to be your best bet. Or you could look into getting it metal printed for fun, but I imagine the cost of that is astronomical.


Are you just after passive cooling? If you're after cooling otherwise you could consider spraying the outside of the intercooler with nitrous.
 

Desert Sasqwatch

Goblin Guru
Still looking for someone with a lathe and mill (and the experience) to know if this is doable, please. Welding 2 parts together, though an option, is not what I am asking.
 

G Atsma

Well-Known Member
Are you doing this for additional cooling, or appearances? Because to be honest, the fins on that size of tube really won't do much cooling, especially over that short of a length.
 

Desert Sasqwatch

Goblin Guru
Short answer: yes. I fully understand the technical aspects of a finned pipe for heat disappation as an engineer. Having double the surface area of a standard pipe will disapate twice the heat, generally stating. The air coming out of the turbo will be somewhere around 350 degrees, so providing a cooling enhanced turbo pipe before it enters the intercooler is a good thing. And having really cool looking turbo pipe won't hurt too. :cool:
 

k.rollin

Well-Known Member
The shop I work in could make something like this, but I guarantee that it will not be cost effective compared to a weldment like those proposed above. I've tried to find a suitable off the shelf extrusion to start with without any luck, though if one exists, that will be the most cost effective way to go. None of my suppliers carry 3.5" aluminum tube with a 1" wall either, which means we're starting with barstock, using the BTA drill to get your 2.5" bore, then moving on to the OD profile machining and turning the bead surfaces for the couplers. In my opinion, the juice ain't worth the squeeze when made from barstock when compared to the alternative manufacturing method already proposed. That said, it would be cool to see, so if you can make it happen, we'll all be watching.
 

Desert Sasqwatch

Goblin Guru
I have researched to find a longitudinal finned tube, cannot locate anything that has the 2.5 ID.

For this idea, an aluminum tube 2.5 ID x 3.5 OD x 0.5 wall will work just fine and is readily available, no need to over complicate the part using bar stock. Lathe work to size the ends (0.125 wall) and form the connection bead (0.150) is a straight forward operation. Milling the fins (0.350 depth to maintain a 0.150 wall) with a horizontal indexing mount to slot at 12 degrees (30 fins) is also not too complex. Setup would take time to get it right.

Rough calculations for the finished part is equivalent to the surface area of a 7 inch (OD) tube versus the 2.75 inch (OD) of a standard 2.5 turbo tube. Surface area for the finned 11 inch of exposed tube is approximately 275 square inches, the 2.5 turbo tube is only about 77 square inches of exposed surface area. The passive heat dissipation is 350% greater and can remove significantly more heat from the charge air before it gets into the intercooler.

Making this pre-cooler tube would cost some $$ to make. It has been suggested to put a barrel intercooler in place of this pre-cooler pipe. While this would be effective, it would also cost at least the same or even more $$ and require increased liquid cooling (heat exchanger, tubing, pump) and greater demand on the already overtaxed electrical system. This is the reason I'm looking at the passive cooling option.
 

Desert Sasqwatch

Goblin Guru
Thank you for your input on your electrical system. This post is not meant for a debate about my electrical system, which will be loaded to 80% of capacity (about 100 amps) with the parts I will be installing with all operating. Please note that the practical upper limit an electrical system should be operated for alternator longevity is 80%, due to cooling limitations, especially in the desert.

The intent of this post is my looking for someone who may be able to make this pre-cooler pipe. I appreciate the idea of welding 2 of the example pipes together, but this solution will also require some machine work to achieve the length of finished pipe I need - 14 inches overall maximum. I would appreciate other inputs if this pre-cooler can be made.
 

pisco

Active Member
Thank you for your input on your electrical system. This post is not meant for a debate about my electrical system, which will be loaded to 80% of capacity (about 100 amps) with the parts I will be installing with all operating. Please note that the practical upper limit an electrical system should be operated for alternator longevity is 80%, due to cooling limitations, especially in the desert.

The intent of this post is my looking for someone who may be able to make this pre-cooler pipe. I appreciate the idea of welding 2 of the example pipes together, but this solution will also require some machine work to achieve the length of finished pipe I need - 14 inches overall maximum. I would appreciate other inputs if this pre-cooler can be made.
Other than aesthetics is there a reason to avoid tig welding fins on a std tube?
 
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Ross

Goblin Guru
Yes this is a possible project.
Since you found aluminum pipe, that makes it a lot easier.
I would use a metal lathe to cut the hose connectors at each end, then make a jig for the tablesaw to hold the pipe, and cut the long fins.
Potentially the hose connectors could be done on a tablesaw too, if you made another jig for that.

These guys even have 3/4" thick wall tubing:
4 OD x .750 wall x 2.50 ID
6061 Aluminum Round Tube
$256 for a 2 foot section.

I have the tools, but no desire to come out of retirement.
The reason I suggested welding earlier, is because I have a metal lathe and TIG welder, and thought it would be the affordable solution. It does have that ugly weld in the middle, but it is only $100 worth of aluminum, and less labor to make it.
 
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Desert Sasqwatch

Goblin Guru
Thanks Ross. The 1/2 inch wall tube I found can be ordered cut to length at about $125, so the initial material outlay is not too big of a hit. Then it's all labor to get a finished piece made.
I fully understand this not a simple task and unretirement to volunteer. I will keep this thread active and maybe someone else who may not have read this posting will take on this task.
If this was 15 years ago I would be doing it myself at my father's business. But a move to Arizona, my father retiring and selling the business, and my not having room to purchase my own equipment hampers an ability to make these ideas into real parts.
Thanks for looking at this.
 

Brian74

Goblin Guru
I never thought about the temperature increase after the turbo, but that definitely seems like a valid concern.

I think Jeff L. is even running a regular intercooler before the liquid cooler on their track Goblin. I’ll be interested in seeing what you come up with.
 
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