Rigi Grip for stainless coolant tubing

[Scott Davis]

Thinking about using Rigi Grip for my coolant tubing which will be exposed in the tunnel under the car. Was thinking this would help with heat transfer and surprisingly the 1.5" is slightly thicker and 15% cheaper than plain stainless. good idea? bad?

1.5" x .035 smooth stainless

1.5" x .048 Rigi Grip

They say it will work http://www.aidic.it/cet/09/18/093.pdf

 

[Terry Oxandale]

By heat transfer, are you referencing the transfer of heat from inside the tube to outside of the tube? Perhaps I'm misunderstanding the data in the link. My read of this document indicated that tube lining irregularities (diamond shaped pattern) enhances heat transfer, which by my understanding, would make the interior of the car even hotter (for our applications) using this type of tubing versus smooth tubing.

 

[PeteB]

That tubing isn't pressure rated. It's made by forming a sheet into a tube and welding. You could have issues with leaks at the weld.

From their website (http://www.rigidized.com/rigigrip.php)- "Our Trim-Tex 8" wide strip is used to create both rail and other shapes. Rigidized<SUP style="FONT-SIZE: 12px; LINE-HEIGHT: 8px">®</SUP> Metals supplies textured tubes to fabricators of handrail systems."

The dimples do provide more surface area, which would improve heat transfer. I don't think it would be a big enough difference to notice.

 

[Scott Davis]

I'm not sure about Rigidized process but I'd assume standard welded T304 stainless tube is made in a similar manner from sheet (though not textured) and should hold up to the pressure of a cooling system without needing seamless tubing. But without a pressure rating there's no way of knowing. Also after looking at the picture and noticing the texture on the inside of the pipe as well, I'm also concerned about friction and potentially decreasing flow/efficiency of the system...and as you say the benefits of heat transfer probably not worth it. Sounds like a pass...If I had extra time I might buy a piece and test it out...I don't. Thanks for comments.

 

[Terry Oxandale]

I used stainless to reduce heat transfer being the tubes lie between the seats. Then I Jet-Hot coated them as well to reduce the heat transfer even more.

 

[Scott Davis]

These run exposed underneath your car or within the chassis somehow? I'm learning how much heat can be soaked from mid engines cars...I don't have experience here yet. I can see how you would want everything insulated on the SLC stainless tubes since they aren't exposed. Sounds like they should be insulated regardless since they'll heat surrounding sheet metal even if open to air. These coolant pipes will be located where the exhaust pipes were located previously on the eclipse. I figured the coolant pipes would be cooler then exhaust pipes and wouldn't need insulating. Appreciate the advice.

 

[mark b.]

Too small for coolant, but if you could find something larger here would be your heat transfer.

https://www.lefthanderchassis.com/v2a/14_viewproduct_group.asp?idgroup=2511674

 

[Jack]

Get a selection of bends here, in 16ga stainless steel.
Tube Bending & Fabrication - Columbia River Mandrel Bending

 

[Richard]

Not to take this too far off topic but what is a reasonable size (OD) for water pipes for a 302?

 

[Scott Davis]

Not to take this too far off topic but what is a reasonable size (OD) for water pipes for a 302?

Long answer

http://www.gt40s.com/forum/gt40-tech-engines-induction-exhaust/13167-cooling-system-questions.html

Short answer

to give you a synopsis of the large thread.

Most of the originals are 1.75" OD feed and return. Alum and SS.

many of the kits are 1.5" OD feed and return

I ended up with 1.5" feed, 1.75" return both .035"wall 304SS.

The new Ford GT44 has 1.25" feed and 2.0" return.

 

[Terry Oxandale]

I used 1.5 all the way through, but put the pump in the circuit just ahead of the engine so that pressure losses to the heads was reduced (and reverse flow implemented - heads got the coolest water first).