wakeech

ok, seriously, azben give it a rest. you are wrong, it's ok to be wrong sometimes.

water alone is a better coolant than water and antifreeze. water and a detergent (interrupting surface tension) is even ebtter than that. there is no reason to think that the coolant will ever boil and turn to steam, that's why there's a pressure cap. if there are overheating problems, you've got a bigger issue than using straight water (as using straight water would actually help defeat overheating).

Rxdriftingaction

u can do so many think to cooling the engine. such as install a biger intake cooler. or try to boost up or reset the cooling fans. or.... but that's a easy way to cooling the engine. just take out the engine cover. look it's goes better or not. i think it may work. even i don't got this kinda problem. cuz i install a big intake cooler already.

azben

tell you what wakeech, you run water in your eight for a month, take a few one to two hour drives and get back to us when its gone out the pressure valve as steam, since you are sure it will work

G8rboy

I'm with Wakeech on this one- after living in South Florida and driving my Miata very hard down there, especially when autocrossing in the summer, I learned to use a water-to-coolant ratio of 70-30 or 80-20 to prevent overheating. Flat out, water alone is a better coolant.

bxb40

There should be diagrams with dependencies of the boiling and freezing points for water-glycol mixtures (glycol should raise boiling point and decrease freezing point). I would say the most water that would not freeze is best. However, glycol might lubricate moving parts and inhibit corrosion, so removing it all without another specific additive is not good also. Once steam forms, the whole system will fail.

rx8cited

Some good info in here on the topic: Water Wetter® Tech Info -> http://www.redlineoil.com/whitePaper/17.pdf

Anyone using Water Wetter in your RX-8: can you tell us what changes you've observed with the car since using it please?

rx8cited

Rotarian_SC

Wouldn't a mixture, even if it was a small amount of solute, create boiling point elevation (due to london dispersion force or other type of molecular bonds that may occur), which would be better?

Reaper Man

all I know- my tranmission column isn't half as hot as it used to be after I got the catalytic converter replaced...

the-jewish-rx8

i think he is right it makes sense if the engine gets hot enough to boil water than it would increase overheating. wate may be the best coolant but what about steam

zoom44

howstuffworks.com-
Cars operate in a wide variety of temperatures, from well below freezing to well over 100 F (38 C). So whatever fluid is used to cool the engine has to have a very low freezing point, a high boiling point, and it has to have the capacity to hold a lot of heat.
Water is one of the most effective fluids for holding heat, but water freezes at too high a temperature to be used in car engines. The fluid that most cars use is a mixture of water and ethylene glycol (C2H6O2), also known as antifreeze. By adding ethylene glycol to water, the boiling and freezing points are improved significantly.

*Pure Water * 50/50 C2H6O2/Water * 70/30 C2H6O2/Water
Freezing Point * 0 C / 32 F * -37 C / -35 F * -55 C / -67 F
Boiling Point *100 C / 212 F *106 C / 223 F * 113 C / 235 F


The temperature of the coolant can sometimes reach 250 to 275 F (121 to 135 C). Even with ethylene glycol added, these temperatures would boil the coolant, so something additional must be done to raise its boiling point.

The cooling system uses pressure to further raise the boiling point of the coolant. Just as the boiling temperature of water is higher in a pressure cooker, the boiling temperature of coolant is higher if you pressurize the system. Most cars have a pressure limit of 14 to 15 pounds per square inch (psi), which raises the boiling point another 45 F (25 C) so the coolant can withstand the high temperatures.

Antifreeze also contains additives to resist corrosion.


so it sounds like to me they are saying water is the best coolant but it needs a little help to stay liquid in the form of chemical additions and pressure.

Rotarian_SC

By the chart provided the pressurized coolant system can't keep the water cool enough by itself, but that it needs some of the glycol for boiling point elevation.

wakeech

but, in a race motor where you would be running ~120 for hours on end, your pressure cap is going to be 18psi or higher. and i like how they are completely oblivious to the fact that it takes (much) less energy to raise the tempurature of that dilute water than it does pure water.

and if your coolant is regularly getting over 120 degrees, you're in a heap of overheating trouble, and coolant isn't the problem. below 0 degrees, yeah, water obviously doesn't cut it.

azben

but wakeech why do you keep talking about race cars when we are talking about the rx8, sides you can fly with your cape

cre8

wow, it is certainly easy to get you hot and bothered, azben. Come on, we are just talking about coolant.

Nemesis8

iTrader: (3)

What about the PWR radiator from Vivid?

http://www.vividracing.com/catalog/p...oducts_id=6136

azben

nah just a good natured joke from my girlfriend, she saw his cape and thought it was funny

Digger1911

Hello all,
need some input from you guys. My 04, 6 speed RX8 is running warmer than normal. The gauge moves slowly to the final resting spot of 3/4. The outside temperature was 116 degrees to 119 degrees . The temperature Gauge reads 3/4 (see picture attached). and pushed coolant by the cap.
The coolant level is not over filled, And the overall performance engine is good, 21 miles to a gallon while running 3/4 on the gauge. at 81 mph 300miles on that tank of fuel. If I turn the A/C off the temp gauge lowers, and reads 1/2 way. The problem with that was without the ac, the sweat got in my eyyes. The oil coolers could have just enough fin damage to create part of the problem, ((I am going to switch out the oil 5w30 for the trip back.)) I have not had time to search the board for related tthreads,

The likelihood the engine tolerates the abuse is slim.

LOOKing for any RX-8 members in Tucson, phoenix and Vegas, how are you keeping your 8s cool.??
714 329-.7 six, six 9 thanks all.
Any help will be greatly appreciated

Fans -- both working, and high speed,low speed operating correctly. ( they come on real close to 205 degree, low speed, and high speed is active with ac on.

T-stat-- checks Good .
--

Digger1911

Snap shot of running temp.

Jedi54

iTrader: (7)

couple of things:
1. turn your TC /DSC back on if you're on the road. No sense in taking any chances regardless of your driving experience. I've seen too many RX-8's totalled because those were off.

2. with ambient temperatures in the 116°F range, be VERY careful about pushing your car too hard. When the dummy gauge moves past it's usual spot of about 1/2, it is because the coolant temps are already approaching 230°F and that is already in the 'danger zone'
Those in the desert area have done a number of things to help cool their cars

Look into the upgraded water pump and thermostat by Mazmart
Upgraded radiator by BHR or Mazmart
annual coolant flushes

Another thing is with the use of devices such as an AccessPORT you can program the fans to come on much sooner and that can help as well.

Easy_E1

iTrader: (2)

LINK

Digger1911

Thank You, Jedi54 and Easy_E1
Which radiator and hood mod ( increased air flow though engine compartment) have you found to be the best?
Jedi54 The DSC has saved me many times. I was doing a fuel trim comparison, dsc (on) verses dsc( off) The picture attached is NOT mine,
but look at it as a reminder.

Jedi54

iTrader: (7)

you're welcome digger.

I have the BHR Radiator, Mazmart Water Pump and Mazmart T-stat.
When in Vegas heat, I could definitely see the difference. A few us of us at the meet had coolant gauges and my temps were noticeably lower.

Just my personal experience.