After the challenge, i want to get a thermostat and such in the car.
Right now, the upper hose is interesting to say the least.
At the back, the factory thermostat housing was welded to the intake, making it essentially an elbow. Connected to it is one of the spring infused universal radiator hoses. 1.25 i think (stock miata diameter). Then, an aluminium cobnector with the water temp gauge sender in it, to a scrap of bulldozer radiator hose i got for free, to a miata radiator.
Its as bad as it sounds.
What i would like to do:
Come out of the factory thermostat housing with a small section of rubber hose, to tubing. Yhe tubing would contain a thermostat, and a pair of bungs. Obe for water temp gauge, one for warning light sender. Then to a short piece of rubber to the radiator.
I just have no idea how to do this, what material to use, what concerns/issues there are, what products (aftermarket or factory) to use, etc.
Tl:dr : i want a thermostat and reduce the few feet of rubber hose to a few inches. Hiw?
For the hard sections, I use sanitary tubing. I get the 90 degree bends for the corners. Works great for headers too.
Sanitary tubing seems to be stainless. And expensive. Is it necessary? Or is it just neat?
Also, am i overthinking it again? Is it really just as simple as bending up some exhaust tube, welding some beads on the end, and sending it?
What diy options are there for the thermostat housing? I thought about using two small block mopar thermostat housing bolted together, but there would be no register for the thermostat to sit in.
Do i need water bypass ability for proper function?
What exactly is the problem with the rubber hose?
I ask because it doesn't look all that different than the standard solution for BP Miata coolant reroutes.
Nothing really. Other than the lack of thermostat, and it just seems janky. Really, nothing. Other than i cant leave well enough alone....
Back in the ‘90’s when I was in the bus manufacturing biz, we used copper tubing.
Usually need -20AN to get it to flow decent and those are $$ in hose and fittings. I usually just weld some alum pipe (sch 40) into the complex shapes and long runs and use simple hose couplers of appropriate size at the ends.
I've used exhaust tubing. Works just fine.
Yeah, sanitary tubing is 304 and while not cheap, if you buy it wholesale, it's not that bad. The bends, though, aren't bends per say, but made in that shape with a perfect radius. And those are expensive. The pic is a bit blurry, but here's a header I made from it:
Some of those bends are store-bought 90's like #1 and 2 runners at the head, and some I bent myself like 3 and 4.
Dusterbd13-michael said:
Nothing really. Other than the lack of thermostat, and it just seems janky. Really, nothing. Other than i cant leave well enough alone....
So the old "M-tuned" Miata re-route kit used a short (~ 4 inch) length of hose to go from the back-of-head outlet to a remote thermostat housing, then a long hose (with a spring in it) to go around to the radiator inlet. Some people report that the short "dead head" hose to the thermostat results in it opening late and then cycling open and closed for a bit, but it works fine on my car and has never been an issue.
Housing: https://www.summitracing.com/parts/MEZ-WN0071
Knurled. said:
I've used exhaust tubing. Works just fine.
This is what I'd do. The regular aluminized stuff should be fine but, if you have a custom exhaust shop around they may even have some cutoffs of stainless exhaust pipe lin their scrap pile
codrus said:
Dusterbd13-michael said:
Nothing really. Other than the lack of thermostat, and it just seems janky. Really, nothing. Other than i cant leave well enough alone....
So the old "M-tuned" Miata re-route kit used a short (~ 4 inch) length of hose to go from the back-of-head outlet to a remote thermostat housing, then a long hose (with a spring in it) to go around to the radiator inlet. Some people report that the short "dead head" hose to the thermostat results in it opening late and then cycling open and closed for a bit, but it works fine on my car and has never been an issue.
Housing: https://www.summitracing.com/parts/MEZ-WN0071
I like that housing!
I wonder if a few bleed holes driled through the thermostat would make it work better
Ill go find some exhaust tube. That seems to be the easy button
Summit sells coolant pipes, I've used them on Plymford. Regular steel, pretty cheap.
For racing, you can't use antifreeze, so steel tubing will rust. On my mx3, they put in a steel section for the water temp sensor, and it was rusted badly. This was clearly a short-term get-it-done-before-the-race-tomorrow setup. I drilled and tapped a bung in the filler neck instead. For my radiator redo, I used 1.5 aluminum tubing and small section of hose connecting them for tight elbows.
I was about to use kitchen drain pipe which was recommended by some. It is chromed brass and while not super cheap, not expensive and also lightweight and some 90 degree sections, and found at all home centers, so available right now.
In reply to nimblemotorsports :
If you're not even allowed to use Water Wetter or another product that has anticorrosives in it, you'll need to pull the engine apart on a regular basis anyway to have the rust cleaned out of the block, replace all the core plugs, water pump replaced due to the impeller rusting away, etc. So a little piece of tubing is a minor annoyance in the grand scheme of things.
(This is something I've had to do for customers... running without any kind of anticorrosive in the coolant does a remarkable amount of damage.)
So, i need to put the brass water temp sender fitting and the warning light fitting in the steel tube. Will be using exhaust tubing.
Is the wall thick enough to drill and tap for npt and seal/hold up?
In reply to Dusterbd13-michael :
No, the wall will not support threads, you need to weld a bung on.
TurnerX19 said:
In reply to Dusterbd13-michael :
No, the wall will not support threads, you need to weld a bung on.
What i thought but was hoping i was wrong ....
If you put a single wire sensor in a piece of metallic tubing that's got rubber at each end, you'll have to add a ground.
Another vote for exhaust tubing and some sort of anti-corrosion additive in the coolant.
Those M-Tuned coolant reroute kits did open the thermostat a bit late because it was isolated from the head with little flow through it. Never caused a real problem AFAIK, but you can definitely see it if you log water temps.
1.25 aluminum tubing. I have a 6" section of it on Datsaniti to "elongate" the lower radiator hose. You can even move your filler cap there for easier bleeding if you want.
if you are going with an external thermostat, I would consider a BMW or Fiat Type (fiat was aluminum on the original 124) to look the coolant back to the engine when it is cold.
Hmm...
Got a link? My homebrew solution failed.
Knurled. said:
I've used exhaust tubing. Works just fine.
Me too. Most exhaust stainless is 304, so it won't last forever, but it lasts a lot longer than rubber. I used copper for a boat motor I built because it looked neat. Seemed to be just fine for the 4 years I had it.
