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-   -   Miata cooling system thread (https://www.miataturbo.net/race-prep-75/miata-cooling-system-thread-79930/)

Leafy Jul 24, 2014 11:21 PM


Originally Posted by Keith@FM (Post 1151150)
Flyin' Miata also offers a PNP kit.

Flyin' Miata 1 800 FLY MX5s

I just wish that the cooler placement was somewhere useful. And IMO an oil cooler kit that comes with pre-made lines should have crimped hose ends, if only for the more professional feel.

ThePass Jul 25, 2014 12:13 AM


Originally Posted by Leafy (Post 1151152)
I just wish that the cooler placement was somewhere useful. And IMO an oil cooler kit that comes with pre-made lines should have crimped hose ends, if only for the more professional feel.

Any placement is going to work well for some, not so well for others depending on their specific bodywork, splitter, etc.
This location lends itself nicely to a NACA duct in the splitter, as I recently advised someone who has this kit to do. :)

-Ryan

Leafy Jul 25, 2014 12:20 AM


Originally Posted by ThePass (Post 1151167)
Any placement is going to work well for some, not so well for others depending on their specific bodywork, splitter, etc.
This location lends itself nicely to a NACA duct in the splitter, as I recently advised someone who has this kit to do. :)

-Ryan

But that naca duct is going to increase pressure in the engine bay...

emilio700 Jul 25, 2014 12:24 AM


Originally Posted by Keith@FM (Post 1151150)
Flyin' Miata also offers a PNP kit.

Flyin' Miata 1 800 FLY MX5s

Nice kit. Same type of Setrab we use. -8?
Our testing indicated a pressure drop between -10 and -8 so we run -10 in every car.

ThePass Jul 25, 2014 01:14 AM


Originally Posted by Leafy (Post 1151168)
But that naca duct is going to increase pressure in the engine bay...

Most oil cooler kits do.
I wasn't saying it's ideal, just that you can work with it. Mine has it's own separate ducting path in and out of the bodywork.

-Ryan

Raisin Jul 25, 2014 02:02 AM


Originally Posted by emilio700 (Post 1147185)
Coolant
While antifreeze has a higher boiling point, it doesn’t reject heats as well as plain water. Most racing sanctioning bodies do not allow any antifreeze in a road race car since it’s damned slippery when it gets onto the track. We use distilled water, half a bottle of Redline water wetter, and splash of antifreeze. Why the anti freeze? To help reduce corrosion and also allows the drivers /crew to more quickly catch tiny coolant leaks. That sharp smell gives it away faster than plain water does.

Have you guy's seen any sort of corrosion (ie: Coolant turning brown) when running a mix of distilled water + water wetter + small amount of coolant?

Rust colored coolant in my RE&RE of my cylinder head indicated to me that my mix of coolant to water was too little and causing the block to corrode.

What ratio do you use?

ccsc Jul 25, 2014 07:18 AM

what is the water temperature delta across the radiator typically (say when driving 70 mph) on a stock car? If it is relatively low, would the oil "warmer" work as a cooler if the coolant was re-routed to it from rad exit?

Leafy Jul 25, 2014 07:19 AM


Originally Posted by Raisin (Post 1151187)
Have you guy's seen any sort of corrosion (ie: Coolant turning brown) when running a mix of distilled water + water wetter + small amount of coolant?

Rust colored coolant in my RE&RE of my cylinder head indicated to me that my mix of coolant to water was too little and causing the block to corrode.

What ratio do you use?

How much did you flush the system? When I put in the new motor I also put in all new coolant lines and a new radiator and flushed the heater core for like 20 minutes with the hose and after a few months I still had brown coolant, but a couple drains of the system later and I think I've finally got it all clean. Getting all the brown potty water out is quite a struggle, and you can get that brown shit even with 50/50 mix.

sixshooter Jul 25, 2014 07:37 AM


Originally Posted by ccsc (Post 1151195)
what is the water temperature delta across the radiator typically (say when driving 70 mph) on a stock car? If it is relatively low, would the oil "warmer" work as a cooler if the coolant was re-routed to it from rad exit?

If the water went from the radiator to the oil "warmer" and then to the mixing manifold, you wouldn't get much flow because there would be little or no pressure differential in the coolant path. It would be better to use it as it is for warm up for a street car and use an external oil cooler with a thermostat (like the RX7 unit) to cool it when it needs cooling. On a race car I expect you would leave it off entirely as mentioned previously.

Keith@FM Jul 25, 2014 12:07 PM

If you want some interesting temperature data across the radiator, here are some numbers for you.

Flyin' Miata : Cooling tech

As for our oil cooler, the lines we use have crimped ends on them for the full professional feel. That must be an out-of-date picture, I'll get around to updating it at some point. We use -8 lines in that kit, but if there's demand we could quite likely do a run of -10.

fail wagon Jul 25, 2014 06:32 PM


Originally Posted by ThePass (Post 1148523)
Here's a snapshot of the AutoCAD file.. this is for the NA hood

https://www.miataturbo.net/attachmen...ine=1405634814

Up until just a little while ago, I was running a hood in which I had these three holes cut out which matched the gaps in the supports below, always loved the look. Made this to fit the same idea.



I took a look at my NB today, looks like I can do something similar on that hood as well. Shapes are a little different but similar layout.
I have a different part coming out of the waterjetter end of this week, so I might have them cut a prototype of this at the same time so I can fuss around with it.

-Ryan

Oh man, please make these. I was just about to cut mine out! Any kind of ETA?

EErockMiata Jul 27, 2014 12:38 PM

Another data point to add to the mix. We did a track day yesterday at Buttonwillow on the new track surface. The temps yesterday were absolutely insane peaking some where around 107 degrees. It was an exercise in monitoring temps for just about everyone out there.

I easily found the limit of the stock cooling system in my car. I had to balance hot laps and monitor the longacre coolant temp gauge I put in like a hawk. I ended up just admitting defeat and short shifting at 6200rpm all day and balance 1-2 hot laps with 1-2 cooldown laps.

Time to put a re-route in and re-evaluate the radiator ducting. Currently I was running with a 100% stock cooling system, oe rad, no ducting, no re-route, oem rad cap. This will be changing immediately.

hornetball Jul 27, 2014 01:56 PM

Re-route is a MUST.

Since you're normally aspirated, I suspect that + plus making sure your OEM air guide + undertray are in excellent shape is all you'll need.

ThePass Jul 27, 2014 06:16 PM

Was out there with Erik (EErock) and many others at Buttonwillow yesterday. Solid heat testing day, well over 100* (and track surface was 145*). Many cars doing the classic fast lap/cool down lap cycle. Previously, I've had to do just that in summer temps of 90*+.
This was the first shakedown of the new v-mount/7-mount/whatever setup, and at 200whp in 105* heat I spent every minute of every session going for it, with peak temps never above 195* water / 235* oil. I even went out in the last bonus session just because I finally could and the car wasn't calling it quits on me. Felt good. My heat exchanger config isn't as conventional as most, but it still definitely makes the case for good ducting and thinking through your inlets and outlets for them, whatever the config may be.
:party:


Originally Posted by fail wagon (Post 1151405)
Oh man, please make these. I was just about to cut mine out! Any kind of ETA?

Trying not to side-track this thread, there's a separate thread for the development of these now. I am picking up some test pieces this week..

Linkage
https://www.miataturbo.net/general-m...nterest-80032/

tomiboy Jul 28, 2014 08:29 AM

Thermostat
The OEM Miata ECU begins to reduce ignition advance and add fuel when the coolant rises past 200-210° depending on the year. Both of these correction table adjustments reduce power. Best power and fuel economy with the stock ECU comes when the coolant temps are kept around 200°. The OEM 195° thermostat is a good place to start with a stock ECU. With an aftermarket ECU or reflashed OEM ECU (Spec Miata), a 180° or even 170° thermostat can unlock a few more hp. We like the Stant “SuperStat” line of thermostats provide the highest peak flow and temp reduction. The 45868 180° SuperStat fits all years 89-05 and is what we use in our coolant reroute.

Emilio can you clarify the above statement? Are you saying a Stant Superstat should not be used with a stock ECU? I have a Rotrex and a piggyback. I have installed the Stant SS 180 T-stat, with hopes of a little temp reduction...is this an issue with the stock ECU?

emilio700 Jul 28, 2014 12:48 PM


Originally Posted by tomiboy (Post 1151949)
Emilio can you clarify the above statement? Are you saying a Stant Superstat should not be used with a stock ECU? I have a Rotrex and a piggyback. I have installed the Stant SS 180 T-stat, with hopes of a little temp reduction...is this an issue with the stock ECU?

You have it backwards. Lower temp is better. Don't over think it.

"With an aftermarket ECU or reflashed OEM ECU (Spec Miata), a 180° or even 170° thermostat can unlock a few more hp."

tomiboy Jul 28, 2014 01:16 PM

This is what is confusing me. You stated:

"The OEM 195° thermostat is a good place to start with a stock ECU. With an aftermarket ECU or reflashed OEM ECU (Spec Miata), a 180° or even 170° thermostat can unlock a few more hp."

Not sure what I have backwards. I know I want temperature lower than my current 210* plus on track

EO2K Jul 28, 2014 01:37 PM

Correct me if I'm wrong, but I was always told that the thermostat manages the minimum temperature in the system. Maximum is determined by how much heat is developed by the powerplant and the cooling systems ability to shed that heat.

You could put a 150° thermostat in the engine and it'll still run 210°+ if the cooling system can't keep up with the heat you are generating.

EErockMiata Jul 28, 2014 01:46 PM


Originally Posted by EO2K (Post 1152082)
Correct me if I'm wrong, but I was always told that the thermostat manages the minimum temperature in the system. Maximum is determined by how much heat is developed by the powerplant and the cooling systems ability to shed that heat.

You could put a 150° thermostat in the engine and it'll still run 210°+ if the cooling system can't keep up with the heat you are generating.

That's how it works afaik.

Emilio, I want to add a water pressure warning light. Could you comment what a good threshold for minimum water pressure would be to set off a warning, shut it down light? Most of the warning lights i see are set @ 3 psi... however you can get some that are .5-24psi adjustable. Just wondering what the low threshold danger zone is. :hustler:

emilio700 Jul 28, 2014 03:09 PM


Originally Posted by EErockMiata (Post 1152085)
That's how it works afaik.

Emilio, I want to add a water pressure warning light. Could you comment what a good threshold for minimum water pressure would be to set off a warning, shut it down light? Most of the warning lights i see are set @ 3 psi... however you can get some that are .5-24psi adjustable. Just wondering what the low threshold danger zone is. :hustler:

Doesn't work that way. If you put it after the reroute somewhere on the rad or top hose, you'll see 10-23psi give or take. We put our sensor on the reroute adapter at the back of the head so we can see signs of head gasket failure as well. Located there, we see 10-34psi.

On cool down lap, the system will draw overflow coolant in from the reservoir and read low pressure. I am accustomed to seeing the C/P light flickering on by around T3 on a cool down lap. So we set our warning trigger below 20psi and above 35psi.


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