I have done what I can for cooing system upgrades but am researching an optimal water/antifreeze ratio. Looking for input, thoughts, recommendations
Here is one article I read:
https://www.sparkplugs.com/learning-center/article/653/quest-for-the-ideal-coolant-ratio#:~:text=However%2C%20this%20ratio%20isn't,for%20cooling%2C%20as%20discussed%20earlier.&text=If%20you%20live%20in%20an%20area%20that%20can%20see%20temperatures,running%20a%2060%2F40%20ratio.

According to it, you only need 10% of an antifreeze mix to maintain anti corrosion properties. I live where freezing is not an issue and does not happen. So I really don't need antifreeze to be a factor. Straight distilled water is actually the best for cooling, but lacks corrosion protection. However I am still tripping on running a ratio even close to 90/10.

As most of you know, I am working on completing a 800whp target NA-T build. My cooling system upgrades are not the best either. But the best I could find/ affordably do. I think that a good coolant ratio will make up for the rest. Currently I have a pretty cheap but upgraded radiator that is double the thickness of stock. It's not thick like a name brand or Mishimoto's you see, nor is it multiple core, but it is the only direct fit aluminum radiator I could find and it was affordable. I put in a 170* thermostat, and plan to have the fans tuned to turn on earlier when tuning. Also HPS silicone hoses.

Right now I have the normal Toyota red pre-diluted 50/50 mix in it with a bottle of Red Line Water Wetter. The more I research, the less I see the need for the Water Wetter. Some people swear by it, but I really think it's meant for race cars running straight distilled water to have some corrosion protection. I think I will just move to a different ratio and leave it out this time. Unless someone has a reason I should still run it? Royal Purple also makes a product called Purple Ice that claims to treat the radiator internally to dissipate heat better. Snake oil?

So considering I will be pushing this engine far past it's factory power and have added a water cooled turbo that the cooling system must handle the heat from too, I need to find the best coolant mix to run. Be it 90/10 if it's safe, 90/10 with an additive? Maybe 80/20? or 75/25? With or without additive? Thoughts? I do want to make sure my engine is safe from deposits and rusting or anything. So 90/10 seems a little worrisome. But I know 50/50 is definitely not needed for a Southern California car. Open to any insight.

 

I guess I'll just follow my instincts on this. In addition to the cooling system modifications I will be running a 1.3 bar (18.5psi) cap. This will raise the boiling point which helps the coolant mix stay liquid at increased temps. Now antifreeze also is what raises the mix's boiling point, so clearly one wouldn't want to run almost straight water. I think I'll attempt to make a 75/25 mix and at least know I have sufficient engine protection and a 75% distilled water concentration for superior cooling characteristics. Might not be as cool as 90/10 for all out race cars, but at least 75/25 is a good deal cooler than 50/50 and just makes more sense for my climate.

 

I suspect we have very similar radiators. Just an ebay made in china aluminum radiator - spec'd for an Aristo. I think you're on the right track with your mixture considerationas. I'm running 50/50 myself as a precaution, should I have the car out in below freezing temps. Even so, the temps have been extremely solid and only move maybe 2 or 3 degrees during a hard pull through 2nd and 3rd gear. I also have a reduced temp thermostat, but I haven't re-wired the fans to run at lower temps than stock (~195-200). This radiator seems to handle heat far better than the little stocker. I really don't know the effect of your turbo putting super hot water back into the flow. I ran water wetter with my stock radiator to help keep temps down - I think it may have had a 4-6 degree impact overall. You might look at some better fans if you're on the stock fans if you're having trouble keeping temps in the target operating range. Stock fans are pretty decent. I weighed using them vs. going with the higher powered Aristo fans. In the end I decided to keep the stock fan motors which draw less amperage, as I didn't want to run the Aristo fans that draw basically double the amperage on the stock circuit, and I didn't want to re-wire (unless I found the stock fans weren't up to task). Overall, I'd say datalog your coolant temps to get a sense of how effective your cooling solution is working and adjust from there.

 

Ebay 210. Aristo. Seperate transcooler.
Got it with bends all four tanks.
My guy straightened them out.
Toyota coolant.
Caribbean tropical climate so say 20-36C in general.

Have yet to dtive it. Fit Aristo like a glove after straightening. Fans hoses plugs. The clamps dont look right but they do the job.

 

Nice, thats a thick rad, way bigger than mine. But part of what I needed was a rad with an internal trans cooler. I am against not running the water cooled one and an external cooler together. The one I got was the only one I could find with the trans cooler. None of the thick ones I looked at offered it. Not even Mishimoto and other big names. I spoke to Griffen Radiator about making me one, but they wanted $800 to custom one. It was too much at the time while I was also dropping thousands on my engine, trans, and diff build. I guess it's not bad for such an important part. Maybe I will do it if I have cooling issues. But I think this one will be sufficient for a street car that sees a few hard pulls once in a while. If it was going to be a track car I would definitely invest in a good one.

 

Thx.
But while I respect your choice of radiator trans cooler, i think you should rethink the pros and cons of a seperate trans cooler.

 

I am running both the water cooled one in the radiator and an external unit attached to the front of my condenser, in case there was confusion.. I am trying to protect my $2200 built trans. I was once taught that you never want to get rid of the water cooler. Even though the radiator is hot AF, it is still a more efficient cooler than air when things get extreme.

 

Now u r having me rethink my understanding or lack of it


Truth is I have a TT z32 300zx since 96. Jap import into TT. Had some tranny issies soby 98 i changed to external only. No probs since.

Maybe one of them mamufacturers of externals can shed light with data.

But I guess you cant go wrong with both.
so that hets me to thinking......
1)trans to ext cooler to rad to trans

And varIous combinations of above. What temps at the same instance. So.ebody had to have checked that.. i ll look around.

And remember I followyour build so i kinda know your tranny would be premiumstuff. (ATF if i recall correctly) And from your earlier cmmy i suspected you were implying rad anc ext coolers🙂

 

There's always been a lot of debate on trans cooling. But my preferred way on all my automatic builds has been to go from the trans to radiator like normal, then to external cooler, and then back to trans. Here's how I see it. Why would you want to run it to the external cooler first only to have it heated back up in the radiator? The temps in the radiator are being regulated by the thermostat and fans. So you can always trust what temps are there, but the external cooler gives that extra bit of cooling after the fluid has passed through the rad before going back to the trans. You don't wan to run your trans too cool. Like the engine, things need to be at their operating temps for the life of the trans. Too hot of course eats the trans up, hence we add external coolers for our extreme applications. So I run it to the rad to get the trans up to operating them, then to the external cooler because most experts agree that around 20 degrees cooler than oem temps makes a huge difference and can double fluid life. I think you accomplish that by running the fluid through the external cooler after the radiator. Thats just how it makes sense to me.

 

I see the sense now in that ypu want the fluid to reach the operating temp RANGE it works best at.

Say 140 -170.

The ext cooler alobe method like I have while it may prevent overheated fluid, it may prevent fluid from getting warm enough to be fullt effective.
so as bobtheoilguy recommends..
tran to rad to thermo to ext cooler or tran based ob thermo open or close.

Thanks TrueGS. No i have to go spend more money and get it right or depend on ambient climate to gwt above 140.

I am kinda cheap but not wealthy u know.

The bummer now is how to heat up!!

Interesting dilema.

 

Soooh.. Living in the tropics. Now understanding your take on the radiator cooler.

Looked at a thermostat to bypass cooler. Brand Daele or simthing like that.

Meantime just ckd my scan tool to see if live data includes Tran fluid temp. It does so I will monitor it in and see what happens. Remember this all started for me ehen I showed my new Arisyo 3core rad sans cooler🙂 So i need to see if the fluid is getting up to temp at least and of coursevif the cooler is doing its job.
Since you opened that can of worms for me, it serms likeca ghermo is vital or mandatory if not using radiator.

 

Cars, and trucks especially, are coming with large external trans coolers and thermostats to warm the fluid up first. So I think if the manufacturers are doing it, and they saw the need for all the time and research and development, you can bet it's pretty important. A car running the radiator cooler and an external cooler is fine IMO. No thermostat needed. It's mostly for large diesel trucks for example. They take much longer to warm up and may be driven miles pulling great loads with a barely warmed up trans. So it's way more important for larger vehicles, but I think if you were to remove the radiator cooler in a car, a thermostat would be a good idea. You also could have way too cold of a trans in winter if the fluid isn't being warmed up by the radiator. For you in the tropics, probably not a big deal though.

 

Interesting conversation. Figured I'd share my experiences. I've been running my transmission coolant exclusively through a separate trans cooler since I did my swap 20k+ miles, 4 years back. Granted it was all on the stock twins. This is with the stock Aristo A340e. I daily drove the car for quite a while. However, upon changing the fluid it looked fantastic earlier this year when I dropped the pan to reseal it. I'm a believer that the single cooler is taking care of the trans fluid quite well for my application. I look at the radiator as a heat adder, particularly useful if you live in a cold climate and/or without a garage. In full disclosure, I've not figured out a way to monitor trans temps, so I am blind to actual temps. Arussto - I'd like to know how you're solving this. But given the condition of the fluid, it's not cooking. I do have a stock setup on my 4Runner with the ability to monitor trans temps through a scangauge. This system runs the fluid through the radiator and then through a small factory trans cooler before returning it. Highest temps are usually seen in the summer during stop and go traffic, reaching as high as 185 or so. Interesting tidbit - when I had the fluid changed on my 4runner, the trans temps ran 15 degrees cooler than before the change. Indicating that old fluid is not as effective at dissipating heat compared to new. No idea how aged the "old" fluid was, as I purchased the truck used.

 

I am glad someone else chimed in as I hope no one was offended by my initial reaction.

Yesterday I monitored trans tem at ambient 26c and saw 73 F in thd fluid. 78f and 165f resp.
This was on a short 4 mile drive.


This is on a Hayden cooler alone.

I get the readings thriugh a foxwell scan tool for toyota JDM as my car is jdm.

i have a tachyon toyota blue tooth code reader too but that does not extract tran fluid temp.

i will have to continue monitoring on warmer 34C days and longer drives and more traffic. I guess i will use the record and playback. I will update when so dine as today ix another rainy day here.

 

Swiched to Farenheit. 173 F cool wet night. 4mile drive.
new oem ext cooler and thermo on the way.