I just read the back of a bottle and it is compatible with anti-freeze, but I don't know about other rust inhibaters. You might need to call them.

 

I just sent them an email asking what they recommend. I will post on here when I get a reply.

 

FYI for anyone mixing coolant additives.

Purple Ice is compatible with the Prestone Anti-rust. I called Royal Purple to confirm that.

I also found another similar coolant additive. RedLine Water Wetter. I heard some good things about this one too.

 

Additives

All year long, I see people having overheating problems, as I go
to stock car races all summer. Everyone seems to go for the
purple ice, the water wetter, whatever to attempt to cool off
a motor that is running hot, and I have NEVER seen it make
much, if any, difference. In a case like yours, you need to bring
it down 40+ degrees, and regardless of what the bottle says, it's
not going to cut it. You have some other issues that need to be
dealt with, and if you can't achieve that last 5-10 degrees, maybe
the additive will help. But first look at your basics, radiator, fan,
a good shroud, correct timing, and a fresh water pump go a long
ways to making a car run a reasonable temp.

 

If your car is overheating in park then you need a bigger fan, if it overheats on the freeway then you need a bigger radiator.

Its the easiest rule to follow and will cure 98% of all cooling problems- provided your pump and Tstat are operating correctly.

If you had a cooling problem to start with and increased the output and size of the engine odds are very good that your cooling problem will get worse- not better.

 

Ponty:

Just went through an overheating issue, try looking through my "Pontiac 400 running HOT" post from a few weeks back. Like Plaintoast said, no magic in a bottle is going to get you to where you need to be temperature wise. Is the radiator new? If not then has it been boiled out? How many rows does the rad have? Is your gauge accurate? What temperature thermostat are you running? What is your total timing set at? Are you using the stock ignition? Are you using vacuum advance? Did you make sure you removed all of the air out of the system? Do you have the divider plate for the water pump installed? Do you have the rubber sleeves that are installed with the water pump? Is the lower rad hose collapsing when running the engine? Just some places to start.

My 400 runs at 205 while idling and about 210 while cruising and 220 when I am accelerating really hard a lot. I am running a 195 thermostat. I believe these engines run hotter because of the use of the 195 thermostat. I use the 195 thermostat because that is what the engine was designed for, and my 400 is fairly stock except for a more aggressive cam. Pontiac designed these engines to run hotter so that they would burn the fuel better, thus lower emissions. I've read somewhere that the idiot light on the dash for overheating does not go off until 260*. If I had a real nasty motor I might consider a lower temperature thermostat just for the fact that the engine is probably producing more heat. There is an article on high performance pontiacs website about a cooling system upgrade, but its big money. The article may give you a few ideas as to where to proceed if you cannot find anything wrong with your cooling system. Can you provide specs for your motor?

 

As for the additive, I wasnt expecting too much out of it. Its one of those things that every little bit helps. I put it in and it did help out a noticeable amount. The engine cooling is not to the point of being bad, i drove it around for 15 min yesterday(80 degrees at the time) and it only got a little above 210.

I am thinking that I need to get a higher volume elec fan for it....It is hard working out all the bugs on a new engine and new trans at the same time.

-The radiator was rebuilt 6 years ago.
-I had a 4 core put into it. Before putting it back in I sent it up to the Rad shop to have it tested and cleaned out. It came back good to go.
-As for the gauge, it is reading correctly. I used an infrared thermo to check it out.
-Timing I have set to 14@idle right now. I need to fiddle with it a little bit. I am having tuning issues, which are slowly being ironed out.
-Ignition is all MSD 6AL, Blaster 2, Pro-Billet Mechanical dist.
-I drilled a couple holes into the thermostat to take care of any air in the system. I also burped it and checked it several times.
-Divider plate is in and the pump is a brand new Edelbrock.


I am only getting a 4 degree drop from the top to bottom of the Rad while at idle. That has me leaning towards not enough airflow from the fan. My big problem is that I havnt been able to drive it enough to see how well it does at a higher speed.

 

For anyone that upgraded to an aluminum Rad, was it worth the money and did it make a huge difference??


I found the article you were talking about....

http://www.highperformancepontiac.com/tech/hppp_0802_pontiac_cooling_system_upgrade/index.html

Here it is in case someone wanted to check it out.

 

Whoops, double post....deleted it.

 

Zipfactor,

what you said about the 195 thermostat rings true. I just got some interesting info on the workings of a thermostat.

I was told people assume getting a 160 thermo will make the car run cooler because it opens up sooner. It will work fine with a car that is required to have one. For the pontiacs, they require the higher temp ones to burn more efficiently.

Having a 160 thermo on Pontiac causes it to run hotter(then the 195) because it is allowing the coolant to flow too fast through the radiator and not let it cool long enough. The hotter thermostats regulate the water a little slower so it has more time to cool off to the proper running temp of the engine. Which on Pontiac is a bit hotter.

This was explained to me by a hot rod builder...makes sense to me. He said it was the same concept as running with out a thermostat...except not to the same extreme.

I just changed mine back up from the 160...Ill see how it goes.

 

"Having a 160 thermo on Pontiac causes it to run hotter(then the 195) because it is allowing the coolant to flow too fast through the radiator and not let it cool long enough. The hotter thermostats regulate the water a little slower so it has more time to cool off to the proper running temp of the engine. Which on Pontiac is a bit hotter."

That is BS! A 160 thermostat will flow the same as a 195 thermostat of the same brand. It just opens sooner.

 

I'm with WDCreech, a 160 flows just as much as a 195. The thought of the coolant needing to be slowed down is a myth. If you don't believe this, then why do they make high flow water pumps? The faster the coolant moves the better. I can explain the principles behind this if you want, but for now I will save me the typing and you the possible boredom. The thermostats job is to keep the engine at a specific operating temperature and to keep the engine from overheating, not to keep the coolant in the engine / radiator longer to absorb / dissipate heat.

 

Thats how it was explained to me. I have not tested the theory, but the info came from a very reliable source. I could have misinterpreted what was explained. Wouldnt be the 1st time . Not to say its right or wrong but it made sense to me because of what happened to an old car of mine.

I had a Jeep cherokee which I pulled the thermostat from because the old one seized up. I didnt replace it at the time because it was a beater car and thought it wouldnt hurt anything. It would overheat only while driving at high speeds. Took me a while to figure out why it would randomly overheat. Pieced it together with prolonged high speed. I researched it and found out that could be what is wrong. Put a stat back in and never had a problem with it after that. Again, something I did to fix a problem and it worked. Not something I tested other then that.

I guess I will see what the difference will be with the 180 stat I just put in.

 

I guess this is how I am thinking of the topic. Please correct me if I am wrong, I am all about learning new things. If I were to stick a cup of water into a freezer for say 1 second and pulled it out...It would warm up a lot faster then a cup of water I left in for 3 seconds. A small difference, but just as an example.

I would think it would be the same concept for coolant. It needs a certain amount of time in a cooling device to dissipate the heat gained from an engine. If it were to flow through the radiator too fast then it would not be able to dissipate the heat it had gained.

Say you were to slow that down, it would give it more time for the air to cool it down. Then again it could be the same for the engine. If it was flowing too slow through the engine, then it would heat up more because of the long time spent in the hotter area.

I would think it would be finding the balanced flow rate through the hot spot compared to the cooling spot. I guess then you would get into the basic properties of radiator fluid. Does it retain heat faster then it dissipates it, or does it dissipate heat faster then it retains it?? Or it is equal, it dumps heat just as fast as it gained it??

I am sure this is getting really confusing. At this point I am just thinking out loud.

LOL I need to take another physics class.

 

As for your cup of water example, yes you are correct in that there will be more heat transfer from the cup from the freezer versus the cup that sits out. This is because there is a larger temperature difference between the cup that was in the freezer versus the cup that sat out. Because of the larger temperature difference from the cup in the freezer, there is more potential for heat transfer.

As for the coolant, lets talk about turbulent and laminar flow. Think of turbulent flow as the bottom of a water fall. The water at the bottom of the water fall is swirling everywhere. Now think of this swirling inside of a pipe. As for laminar flow, think of a calm flowing stream. Now turbulent flow is ideal in the cooling system because more of the fluid is contacting the tube walls because of the swirling. Laminar flow does not transfer as much heat because not as much of the fluid contacts the tube walls, thus transferring less heat. Now if you slow the coolant down, it is going to become less turbulent, and therefore transferring less heat. There is a point where the flow could be too fast, but in an automotive application I would say this would be almost impossible with the equipment available.

"I would think it would be finding the balanced flow rate through the hot spot compared to the cooling spot. I guess then you would get into the basic properties of radiator fluid. Does it retain heat faster then it dissipates it, or does it dissipate heat faster then it retains it?? Or it is equal, it dumps heat just as fast as it gained it?? "

The rate of heat transfer from the fluid to the air is dependent on the amount of surface area and the temperature difference between the fluid and the surrounding air. So as you can imagine, and as you have probably seen, your car typically run hotter on a 100* day versus a 70* day. If your exiting coolant is 200* and the outdoor temp is 100*, the difference is 100*. If you take the exiting coolant of 200* and an outdoor temp of 70*, the difference is 130*. Therefore on the 70* there is a higher potential for heat transfer.

I hope this clarifies things.

 

66Ponty,
I'm going to answer your question about switching to an aluminum radiator. When my goat was just back-halved, I was running a 474 stock block Pontiac and it had a 4 core cross flow radiator. The water temperature usually got to about 215 or 220 on the 1/4, but came down to about 195 by the time I got to the pits. I changed to a Griffen 2 core w/ 1-1/4" tubes aluminum, and the temp rarely got over 200, unless I neglected to tun on the electric water pump. An electric water pump moves the water at a consant speed so that it spends the same amount of time in the engine or radiator. Mezeire now makes a Pontiac pump that can withstand the heat of a street engine. More expensive than the race only pump, but will last longer, on the street.

 

just my 2 cents but i have heard that to much rad can be bad cuz the heat from the first couple rows transfers back to the last rows and wont let it cool as much

 

Creech...good to know. I will keep that in mind if I my cooling decides to get too hot. I fixed my tuning issues earlier and took her for a spin. She never got above 210 on the temp. Was only for a mile or 2, but it was 90 degrees out. I am going to fabricate a shroud here in the next week. Also get an AC sealing set like the Pontiac magazine article talked about.

Zip
Your description makes sense. I take everything into perspective when it comes to working with cars, especially older ones...sometimes you never know.

Thanks for the input guys!!

 

I guess this is how I am thinking of the topic. Please correct me if I am wrong, I am all about learning new things. If I were to stick a cup of water into a freezer for say 1 second and pulled it out...It would warm up a lot faster then a cup of water I left in for 3 seconds. A small difference, but just as an example.

This is a bad example.

Think about the temp outside the freezer rapidly rising the longer the cup sits inside.

 

66 Ponty:

I would say that 210 at 90* outside temp is fine (especially if you are running a 195* tstat). You may want to take it out for a while longer when you get a chance because my car doesnt start heating up until around 20 minutes into it. Have fun!

 

just my 2 cents but i have heard that to much rad can be bad cuz the heat from the first couple rows transfers back to the last rows and wont let it cool as much

chevyman420,
How is that possible? Heat transfers from the water to the aluminum or copper, as it passes through the radiator, and then it transfers to the air as it passes through. Heat does not transfer from one part of the radiator to another as long as cooling air is moving through it.

 

66 Ponty:

I would say that 210 at 90* outside temp is fine (especially if you are running a 195* tstat). You may want to take it out for a while longer when you get a chance because my car doesnt start heating up until around 20 minutes into it. Have fun!

My engine warms up very fast....a bit too fast in my opinion.

I am starting to get really frustrated...I took her out last night for 30 min and the temp sat around 225-230....also my trans temp was sitting at 200.

I was driving around at 45mph and it was 65 degrees out. So I shouldnt have had any problems. The fact that I didnt have a fan shroud shouldnt have mattered either because of the speed I was driving.

I know I am having tuning issues, but I didnt think that would cause the engine to run so hot...am I wrong?

Back to square 1 and retest everything.

 

66Ponty:

At 45mph I sometimes have to kick my fans on (I have an electric setup for now until I switch back to mechanical). You will need that shroud for lower speeds. If your vacuum advance is not working that can definately cause your car to overheat, especially at part-throttle. I would get those to items squared away and then see where you are at. By the way, what is your total timing set at?

 

Do you have the right water pump? If you are using a serpenting you need a reverse rotation one and for a v belt you need regular rotation. I put a sbc in a toyota and put the rad in the bed and thought I could just hook up the hoses and be fine and always overheated then I switched the hoses and have never had a problem since.

 

I guess this is how I am thinking of the topic. Please correct me if I am wrong, I am all about learning new things. If I were to stick a cup of water into a freezer for say 1 second and pulled it out...It would warm up a lot faster then a cup of water I left in for 3 seconds. A small difference, but just as an example.

I would think it would be the same concept for coolant. It needs a certain amount of time in a cooling device to dissipate the heat gained from an engine. If it were to flow through the radiator too fast then it would not be able to dissipate the heat it had gained.

Say you were to slow that down, it would give it more time for the air to cool it down. Then again it could be the same for the engine. If it was flowing too slow through the engine, then it would heat up more because of the long time spent in the hotter area.

I would think it would be finding the balanced flow rate through the hot spot compared to the cooling spot. I guess then you would get into the basic properties of radiator fluid. Does it retain heat faster then it dissipates it, or does it dissipate heat faster then it retains it?? Or it is equal, it dumps heat just as fast as it gained it??

I am sure this is getting really confusing. At this point I am just thinking out loud.

LOL I need to take another physics class.

The problem with that theory, is if it's pumping too fast to cool in the radiator, wouldn't that mean, conversely, that it's also flowing too fast through the engine to get hot in the first place?
Old wives tale about flowing too fast to cool down.