How Much cooler will 30/70 run than 50/50?

[NitroM3]

A BBin 69 Camaro running the temperatures described is hot.
Those who have owned modified 67-72 Camaro's know this .
Mike pm me and will talk.

 

[JeffKeryk]

As others have posted, your temperatures are nothing to be alarmed about.
If you want to lower temps, I suggest:
More radiator, either size or efficeiency, or both. The aluminum 2 row radiators have huge coolant tubes.
More coolant flow to move more heat. I used to run Flow Kooler water pumps.
More air across the radiator; a shrowd is always a good idea.

I have never used electric fans on my classics. I like a steel AC fan (7 blade) and a good thermal clutch.
The thermostat only sets opening temp. Unless it is partially stuck, it does not cause high temperatures. I generally ran 180* 'stats.
Around town stop-and-go you have less air flow and perhaps poorer coolant flow.

If you are running a vacuum advance distributor, run full vacuum at idle and curve distributor accordingly. Ported vacuum is for smoggers that are designed to run hotter at idle.

Find the weak spot.

 

[vavavroom]

30% coolant is likely the minimum.concentration of coolant you'd want to run. And you'd have to make sure that the particular coolant does offer sufficient corrosion inhibition at that concentration. I'd probably go no lower than 40% coolant to be on the safe side.

 

[NitroM3]

I have many friends all,over the US that have BB in Camaro's that don’t run those temperatures. None of my Camaro's with BB or extremely modified SM in Sacramento ever ran those temperatures. My friend that owned ChevyLand with their Camaro’s never ran those high a temperatures . For one reason you all are looking at the wrong area of the engine. From what I have read so far posted no one has owned a 1967-1972 with a BB. I know from this point I am sure to get the laughing likes and usual responses . This is why I asked Mike to pm me. After I talk with him he is more then ok to post what we talk about.

 

[JeffKeryk]

From what I have read so far posted no one has owned a 1967-1972 with a BB. I know from this point I am sure to get the laughing likes and usual responses .

Do these cars count? '68 L36 Corvette, '65 4-4-2

 

[Lubener]

I've got a modified 454 in my 69 Camaro and it runs a little warm. I've heard that if I changed the coolant mix from the over the counter 50/50 to 40/60 or even 30/70 with the adder being distilled water... it might run a little cooler. Has anyone ever experimented with cooling mixes alone and seen any gain? I know water is the best coolant on the planet, but I also know that coolant helps lubricate the system and has additives that will prolong the life of an engine and parts. And of course... it gives protection from freezing. My car is a 3 season restomod, it mainly sleep in the garage during the winter, and I only take it out after a good rain that washes away the salt. Temps in my garage have never gone below 15° and this car has never ever been left outside in all the years I've owned it. So a 30/70 mix won't give me -45° protection, but I think it'll be good to around -10°?

When I say warm, on an 85° day this summer running down the highway the temp gauge shows around 195-200. I have dual 12" eFans that are electronically controlled (PWM) to go on at 195°. I would like to get the temp down on the highway to around 190° so the fans will shut down and just let the 65 mph breeze do its job. If I get into traffic, the temp will go up to around 210-220 and stay there pretty much unless I can't move. The car has AC and air has to flow through the AC condenser and then through the radiator. One other alternative is to add a pusher fan out front, another is to find 2 new eFans that pull more air thru the fins. But before I spend more money on fans I want to think about the coolant mix.

Opinions?

Your engine's temperatures are fine. You don't need to do anything. Changing the coolant ratios will not change your engine's operating temperatures, only the coolant's freezing and boiling points.. I would run a 50/50 mix, giving a boiling point of 265 degrees. You are far from that.

 

[Jetronic]

The heat capacity of a 30/70 antifreeze mixture is approximately 10% higher than a 50/50 mixture, which is barely significant. Pure water has about 20% higher heat capacity than a 50/50 mixture. The metal temperature in the engine would theoretically run cooler with a weaker antifreeze mixture since the coolant would absorb more heat before it's temperature rose, but calculating how much cooler would probably take a super computer. Just a hunch, but I would bet that a 10 degree cooler thermostat would have more effect on engine metal temperature than a weaker antifreeze mixture.

The surface temp reduction will closely follow the reduction in boiling point temperature of the new mixture as most heat transfer happens from the nucleate boiling of the coolant near the engine surface. You might not see this reduction in the bulk coolant temps as that is regulated by the thermostat.

 

[Davejam]

People saying lower coolant ratio won't change operating temperatures are wrong.
This is true if you are running at or below the specified temperature of the thermostat...but above that it will absolutely transfer heat better and lower operating temps.
There is a reason nobody that is seriously racing is using 50/50 mix. They would be using 100% water with additive or just a higher concentration of water.
This is the easiest thing to do. Whether it lowers it enough to satisfy you're requirements, tough to say, but try it before getting into more complicated maters.

In all situations it would be beneficial to run the lowest coolant concentration that will give you the freeze protection you need.
I'm in FL, I could run lower than 70/30 all year long without batting an eye. I run about 60/40 for some safety margin. But also don't have any heat issues.

The only other question to ask is if your condenser/radiator coils are clean.

 

[bullwinkle]

I never saw what thermostat you are running, but, for ~$10 I would try one of these to see how it does-

1972 CHEVROLET C30 PICKUP MotoRad 45356 MotoRad SuperStat Thermostats | Summit Racing

Free Shipping - MotoRad SuperStat Thermostats with qualifying orders of $99. Shop Thermostats, Mechanical at Summit Racing.

www.summitracing.com

I've pretty much been running Stant Super Stats in everything, others don't seem very reliable. It may make a difference, or at least slow down the heat somewhat. (I don't know what 454 you're running, so I picked one at random)

 

[Rand]

Do these cars count? '68 L36 Corvette, '65 4-4-2

No only Nitro has the knowledge to fix one.


This is clearly an issue that can be resolved by part changing some combination of

thermostat, radiator, fan, shroud .

If the current temps are too hot for the OP.

I had to laugh at

For one reason you all are looking at the wrong area of the engine. From what I have read so far posted no one has owned a 1967-1972 with a BB.

I'm not sure anyone else who mods econobox cars has an EGO that is bigger

 

[zray1]

When I say warm, on an 85° day this summer running down the highway the temp gauge shows around 195-200. I have dual 12" eFans that are electronically controlled (PWM) to go on at 195°. I would like to get the temp down on the highway to around 190° so the fans will shut down and just let the 65 mph breeze do its job. If I get into traffic, the temp will go up to around 210-220 and stay there pretty much unless I can't move.

Opinions?

First of all, on a ‘60-‘70’s era car, 210 to the mid 220’s is not overheating. Using my experience with vintage Fords (sorry, Chevy guy) as an example, millions of them came stock with the 195 F thermostat. That thermostat doesn’t even fully open until 212 F.


Changing your thermostat won’t help , as it just sets the low temperature, not the high point.

As long your temp comes down once the car is moving I’d be very satisfied with any standing temperature in the mid 220’s or less.

Previous posts make a very good point regarding the electric fans . Electric fans only selling point on a classic car is that they can move a moderate amount of air at idle. But in your case they seem too small for even that benefit.

A good sized clutch fan with a well designed shroud is a very good cooling solution for classic cars. If I were building classic cars again, I would first put the clutch fan on them. Simple, low cost, and doesn’t require a Higher capacity alternator like a decent electric fan needs, not to mention the requisite relays and improved wiring.


Z

PS but to answer your question re the antifreeze ratio, I switched 100% distilled water + WaterWetter in my ‘02 Jaguar XKR for the non-freezing months and only got an 8-10 degree F cooling benefit. I don’t think 70% water will help you that much.

 

[mk378]

There is a reason nobody that is seriously racing is using 50/50 mix

Most racing rules require plain water, because glycol is slippery when spilled on the track.

 

[Mike/Mass]

Wow... a ton of suggestions and more. OK, how about I post some pix of the setup. That might help. But first a simple explanation of the PWM setup. It is not infinitely adjustable. The manufacturer offers 160°, 180°, and 195° sensors that are attached to the radiator tank next to the outlet hose neck. My current thermostat is a 160° EMP/Stewart and I just switched last week from a 180° EMP/Stewart. Haven't noticed much of a change in the situation, it just takes a couple of minutes more to get to that 195° level where the fans kick in and don't stop.

The shot above shows the engine side of the custom aluminum shroud which measures 23" wide and 16" high, same as the radiator core. The two fans are 12" and the fan assembly is out of a Ford Contour SVT. Supposedly with zero static pressure, they can pull around 3500CFM total. That means maybe 3000 CFM behind a radiator and AC condenser. There's no official rating, that's a guesstimate made by numerous people who have used these fans on other rides compared to supposed known CFM dual 12" fans.

This shot shows the radiator side of the shroud. I have a dozen BeCool rubber pass thru flaps mounted so that at highway speeds, I can get more airflow through the system. At slow speeds the draw created by the fans keeps the flaps tight against the shroud so its not pulling engine heated air in. The shroud is sealed around the perimeter with a dense cell foam (I used a corvette kit for that).

Between the big block and the radiator, there's not much space when you run a serpentine belt system. I don't think this affects the heat but I'm showing the clearance to point out that there isn't much room for conventional fans and factory shrouds. Likewise, I choose this fan setup because others have used them on similar big blocks with good results. So if I switch fans, I have to be very concerned about depth.

This shot shows the shroud without the fans in place. Theres about 15/16" of air space between the inside of the shroud and the radiator core. The way its set up now, I can lift the entire shroud/fan assembly out with minimal wiggling.

This overhead shot shows the entire layout of the engine bay and the radiator closeout panel that supposedly helps the road air on a path through the condenser and radiator.

Not the best shot to show the closeout panel removed, but you can see the plumbing for the condenser before the condenser was actually fitted in there. Its almost the same size as the radiator core, maybe 3/4" thick? One option is a "pusher" fan mounted in front of the condenser switched on at 195° to increase airflow.

The way the PWM is setup, I can't switch the fans off at 200° while riding on the highway to see if airflow alone would do the job. In theory, a belt driven clutch fan would not be normally engaged at highway speeds and you would rely on a 45-65 mph breeze to flow the radiator properly. It sounds like changing the coolant mix would have little to no effect so that probably points to more airflow via different or an additional 3rd pusher fan. But keep the comments coming, its interesting to see all your thoughts.-Mike

p.s. here's my beast.

 

[Davejam]

Most racing rules require plain water, because glycol is slippery when spilled on the track.

Yes, that is also true, but doesn't negate what I said. In racing you're pulling out all the stops to keep the system as low a temperature as possible.

Wow... a ton of suggestions and more. OK, how about I post some pix of the setup. That might help. But first a simple explanation of the PWM setup. It is not infinitely adjustable. The manufacturer offers 160°, 180°, and 195° sensors that are attached to the radiator tank next to the outlet hose neck. My current thermostat is a 160° EMP/Stewart and I just switched last week from a 180° EMP/Stewart. Haven't noticed much of a change in the situation, it just takes a couple of minutes more to get to that 195° level where the fans kick in and don't stop.

The only thing that stands out to me is how hot it might be in the engine bay and whether you're really getting cooler air accross the radiator...so how the fans are oriented and the flaps that you mention if they're actually functioning like you expect them to.

 

[OVERKILL]

Wow... a ton of suggestions and more. OK, how about I post some pix of the setup. That might help. But first a simple explanation of the PWM setup. It is not infinitely adjustable. The manufacturer offers 160°, 180°, and 195° sensors that are attached to the radiator tank next to the outlet hose neck. My current thermostat is a 160° EMP/Stewart and I just switched last week from a 180° EMP/Stewart. Haven't noticed much of a change in the situation, it just takes a couple of minutes more to get to that 195° level where the fans kick in and don't stop.

View attachment 72296
The shot above shows the engine side of the custom aluminum shroud which measures 23" wide and 16" high, same as the radiator core. The two fans are 12" and the fan assembly is out of a Ford Contour SVT. Supposedly with zero static pressure, they can pull around 3500CFM total. That means maybe 3000 CFM behind a radiator and AC condenser. There's no official rating, that's a guesstimate made by numerous people who have used these fans on other rides compared to supposed known CFM dual 12" fans.

View attachment 72297
This shot shows the radiator side of the shroud. I have a dozen BeCool rubber pass thru flaps mounted so that at highway speeds, I can get more airflow through the system. At slow speeds the draw created by the fans keeps the flaps tight against the shroud so its not pulling engine heated air in. The shroud is sealed around the perimeter with a dense cell foam (I used a corvette kit for that).

View attachment 72299
Between the big block and the radiator, there's not much space when you run a serpentine belt system. I don't think this affects the heat but I'm showing the clearance to point out that there isn't much room for conventional fans and factory shrouds. Likewise, I choose this fan setup because others have used them on similar big blocks with good results. So if I switch fans, I have to be very concerned about depth.

View attachment 72302
This shot shows the shroud without the fans in place. Theres about 15/16" of air space between the inside of the shroud and the radiator core. The way its set up now, I can lift the entire shroud/fan assembly out with minimal wiggling.

View attachment 72303
This overhead shot shows the entire layout of the engine bay and the radiator closeout panel that supposedly helps the road air on a path through the condenser and radiator.

View attachment 72304
Not the best shot to show the closeout panel removed, but you can see the plumbing for the condenser before the condenser was actually fitted in there. Its almost the same size as the radiator core, maybe 3/4" thick? One option is a "pusher" fan mounted in front of the condenser switched on at 195° to increase airflow.

The way the PWM is setup, I can't switch the fans off at 200° while riding on the highway to see if airflow alone would do the job. In theory, a belt driven clutch fan would not be normally engaged at highway speeds and you would rely on a 45-65 mph breeze to flow the radiator properly. It sounds like changing the coolant mix would have little to no effect so that probably points to more airflow via different or an additional 3rd pusher fan. But keep the comments coming, its interesting to see all your thoughts.-Mike

View attachment 72305
p.s. here's my beast.

Mike:

Thanks for the additional information, and beautiful car BTW!

OK, since you are considerably above your thermostat temp on the highway, it sounds like you don't have enough radiator. While the Contour fans aren't as good as the Mark VIII fans, they shouldn't be inadequate. Going down the highway, airflow through the rad should be sufficient to keep the temp around that of the thermostat and clearly that isn't happening. Is there any factory shrouding or ducting that might have an impact on airflow through the rad that may have been removed?

FYI, a study done years ago indicated that an 180F coolant temp is right around "optimal". Going below that increased engine wear, going above that resulted in power loss because of the requirement to pull ignition timing.

I've used both a Taurus fan (on my modified fox body Mustang) and a Mark VIII fan (on my modified Town Car) and they were both more than capable of keeping the engine around the thermostat temp. The Mark VIII fan would kick on at 190 and draw it down to 185 rapidly. I used a more primitive setup than yours (large RV relay with on/off temps), while the Taurus fan was a bit slower so I had it kick on a bit lower and had it kick off closer to 180.

What are you using for a radiator? Is the option of going larger (more cores or taller/wider?) available? It looks like a nice aluminum unit, but clearly you are not able to properly shed the heat to keep it at thermostat temp.

 

[NitroM3]

It’s not the cooling system.. lol
And Rand ya I do know and made lotsa money doing it over the decades. Lol

 

[OVERKILL]

It’s not the cooling system.. lol
And Rand ya I do know and made lotsa money doing it over the decades. Lol

I think Rand's issue is that you come off like a pompous know-it-all and it tends to annoy people. I know you are aware of this, having discussed it openly in the past, but current trends seem to indicate you aren't doing much to address it, FWIW. Also, suggesting people PM you for "secret squirrel handshake" type advice goes against the premise of a discussion forum where these sorts of things are, as the name would imply, discussed in the open.

Other possibilities are that the timing is insanely retarded or it is running crazy lean and producing a wicked amount of excess heat, but both those things should be noticeable. His observations point to a lack of ability to shed heat, which comes back to the cooling system. Properly setup, that configuration should keep it right around thermostat temp without the fans going down the road, clearly, that's not happening.

A few possibilities:
- His serpentine setup is seriously underdriving the water pump (relatively unlikely)
- Factory shrouding/ducting that was in place to direct air through the rad is missing
- The rad isn't big enough (seems unlikely, that's a large rad)
- The condenser is blocking adequate airflow

If you have other ideas, bring them forward, as I said, that's the whole point of the board. There are plenty of extremely intelligent people on here, and nobody is casting shade on your expertise/experience. The idea is to share information not hoard it, that way everybody benefits.

 

[NitroM3]

I think Rand's issue is that you come off like a pompous know-it-all and it tends to annoy people. I know you are aware of this, having discussed it openly in the past, but current trends seem to indicate you aren't doing much to address it, FWIW. Also, suggesting people PM you for "secret squirrel handshake" type advice goes against the premise of a discussion forum where these sorts of things are, as the name would imply, discussed in the open.

Other possibilities are that the timing is insanely retarded or it is running crazy lean and producing a wicked amount of excess heat, but both those things should be noticeable. His observations point to a lack of ability to shed heat, which comes back to the cooling system. Properly setup, that configuration should keep it right around thermostat temp without the fans going down the road, clearly, that's not happening.

A few possibilities:
- His serpentine setup is seriously underdriving the water pump (relatively unlikely)
- Factory shrouding/ducting that was in place to direct air through the rad is missing
- The rad isn't big enough (seems unlikely, that's a large rad)
- The condenser is blocking adequate airflow

If you have other ideas, bring them forward, as I said, that's the whole point of the board. There are plenty of extremely intelligent people on here, and nobody is casting shade on your expertise/experience. The idea is to share information not hoard it, that way everybody benefits.

Overkill sorry to let you know reading dozens of threads both past and present I am not the only member that suggested to go PM. I also clearly said that Mike is more then ok with posting what we talk about.

What Mike is having concerns about is be far not new to me and easy to correct. It’s what I have done as business successfully for a long time. You and others still think how did you insult me in your words “pompous know it all” lol if I had posted that Astro would be all over me . Lol

I don’t Squrill “ my information and really do try to help. But time and time again to many debate or disregard my help and information and seem to want to capitalize on my posting style,grammar,spelling and use of the English language.
Yet I see members everyday with the same problems in that area of education. Lol

So again I will say you are Guessing in the wrong place . Maybe if I keep saying this the other experts will figure it out .

 

[Chris142]

Those fans are blocking the air from going through the radiator. If you removed them and drove on the hwy that it would run cooler.

 

[zeky]

When I used to race, build engines, and hot rods, I would use Moroso water restrictors with a 40/60 (40% Green coolant 60% Distilled water). My dad showed me this trick. He used to race as well.

Coolant is illegal on many tracks today. Too slippery. Instead they run water and water wetter.

OP needs to understand what a thermostat is.