Thanks mang.

Well I am running an 8374, the 7064 in the pictures was from another project that I tried since 8374 was backordered at the time.

My misunderstanding

No worries! What turbine housing are you running on there? Twin Scroll?

Have got some wiring done, and did the modifications to the water pump to go with an external pump. The Meziere water pump is on its way as well! I went with -16AN.

https://www.miataturbo.net/attachmen...1&d=1382722647

https://www.miataturbo.net/attachmen...1&d=1382722647

https://www.miataturbo.net/attachmen...1&d=1382722647

https://www.miataturbo.net/attachmen...1&d=1382722647

https://www.miataturbo.net/attachmen...1&d=1382722647

-16, like a boss.

Never seen anyone do what you did to a waterpump before. That is pretty cool.

Yeah, was thinking -12, but then I was like whatever. Looking on the net people seemed to go with either.

It was actually pretty easy and the cool thing is the -16 fitting fits very well in the plastic cover hole without any modifications!

I would have figured you'd do -20 for coolant lines, but it looks wicked fucking slick anyways.

Well you don't want to go too big. The thermostat and water pump are usually restrictions to slow the water down to maximize heat absorption. So the smaller -16 (which is still pretty big) allows the water to slow down a bit!

Thank you! Once the water pump shows up, I can fire the engine up hopefully! The ID1000's just showed up last night too!

The thermostat's restriction isnt to slow the water down, its to create a pressure differential. You really want to flow the most volume of coolant possible in order to move the most heat. The size hose really just depends on how much you're flowing, but stock is 1 1/4ish which would be -20.

If the water moves too quick, you will not absorb the heat fast enough. Trust me, we have used -16 before (and that is on rotary engine which produce quite a bit more wasted heat) with success. You go up to -20 and -24 and you will have localized overheating issues. The bigger is better does not work in this situation.

Thanks for pointing it out though. It's good to discuss these things!

Science does not endorse this statement.

I was really confused at first, I thought "All that work and you didn't even do a coolant reroute?" since it looked like you were taking coolant out the front of the head.

That's what I get for looking at the pics before I read.

You are right, the more flow, the more heat is taken away based on the science. So there is a fundamental flaw with my statement.

However there is a flaw in your statement: the area of the pipe in the system does not effect the flow directly. It effect the pressure drop across that pipe. So that means the pump will need to work harder to overcome that pressure drop. So saying because a pipe is 1" or 1.5", the flow across them will be more is not correct. If you put in 10gpm in there, 10gpm will come out. However it takes more force to get that 10gpm across. So the bigger size allows for less pressure drop.

Right, that is why I said the hose should be sized based on the pump flow. I was also assuming mazda already did that engineering for us and your electric water pump flows as much or more than the stock pump.

Well Mazda's engineering was not perfect as the Miata does have hot spots (mostly due to the FWD engine in a RWD config). I have about 3.5ft (let's say 4ft of hose) were it is -16, rest is stainless pipe of 1.25" and bigger. The pump does not see much of a difference in pressure drop between the two -16 and -20 sizes. In addition Mazda did just their pipe to allow for minimal pressure drop a factory pump can take. At the end of it, the packaging and size of the -20 was sub-optimal and knowing -16 work just fine I went with that option. If you search most people are running -12 or -16 with this setup. I believe -12 is too small.

Awesome! I guess I hadn't checked this build out in a while. Looks badass! What waterpump will you be going with? I really want to go electric, but I don't really have a reason why at this point other than it looks badass lol

Thanks! I have ordered the Meziere 55GPM and should be here Nov 5-Nov 15th according to tracking: Meziere Enterprises

I am putting the alternator on the diff as well as the water pump housing was pointing to the wrong direction, so it was an easy decision. In addition not having a thermostat, it is nice to have a pump to allow for a quicker warm up since I can have the pump off and controlled by the MS3.

^THIS! My Dads street stock had the alternator mounted on the diff. I have always wanted to do it with my car.

It does free up lots of room in the engine bay, reduces the noise that is introduced around the sensors and it's pretty much free energy since it's from the wheels.

On the other hand it does increase my unsprung weight, but at least it's on the rear! We shall see how my cast steel to steel weld will hold up!