the-jewish-rx8

Ok i know that the rx8 engine runs hotter than most cars. i know there is advice on what to do about it but its scattered through threads so lets brain storm on how to fix the problem. i think the engine runs better and smoother when cooler. if there are any threads like this im sorry iguewss i didnt look hard enough

Genom

Unless your planning on making drastic changes in the airflow pattern of the car, there's not much you can do. As far as I know engine heat isnt an issue except for a select few who end up burning coil packs in certain situations.

the-jewish-rx8

well i dont know if this is a joke or not but someone sugested running the air intake into the cabin where it can suck in the air condionting

mysql101

I use water wetter. I don't know how much it cools, but the temp guage is down several bars lower than normal. Given how much antifreeze is in my car, I'd guess somewhere around 10-15 degrees cooler.

robertdot

HAHHAHAHA. That's funny. Maybe safer than a CAI. Too bad the AC sucks.

Seriously, if anyone want's to try this, I'd be interested in seeing how it turns out.

epitrochoid

i can tell you how it will work....

take the intake box off, hold you hand near the TB, have a buddy floor it to redline. I dont think the AC flows that much air:D

shelleys_man_06

At least you're thinking. Like Genom said, there isn't much you can do about improving the cooling system on a stock engine. There's no point. My rule of thumb is to match your cooling system on how much power you're trying to make. If your cooling system is having problems in stock form, getting a bigger radiator isn't going to solve it.

zzum-zum

What is water wetter?

mysql101

http://redlineoil.com/products_coolant.asp

You should be able to pick it up at any auto store. It's about $7 bucks

G8rboy

While it might help slightly reduce intake charge temps, the occupants would probably go deaf from the noise in the cabin. This was done several years back with a beater racing Miata while screwing around with CAI designs, and they said the noise was unbearable.

wakeech

it's a etergant substance which breaks the surface tension of the coolant (water) allowing a greater rate of heat exchange.

jewish-RX8, if you're worried about engine temps, you could try this and also try running less anti-freeze (basically straight water, for the summer, or if you're in a climate which never comes close to freezing even all year around), which will give you a higher heat capacity, allowing the coolant to stay cooler while radiating the same amount of heat.

Rotarian_SC

It's hot, really? Yesterday when I did an oil check I found a frog literally cooked onto my front sway bar! It didn't all come off, and the bottom of it was blackened from the heat, and I have no idea how it got there.

My solution to keeping the engine cooler is to drive faster :p

rx8cited

How do you do that in stop-n-go traffic ? Or do they not have that in SC? I just ordered a case of Water Wetter. .

rx8cited

Rotarian_SC

I drive 30% city 70% highway, and there really are only 3 traffic lights on a trip to work, but it is SC so nobody lives here and you can just run the red ones.

azben

[QUOTE=wakeech]it's a etergant substance which breaks the surface tension of the coolant (water) allowing a greater rate of heat exchange.

jewish-RX8, if you're worried about engine temps, you could try this and also try running less anti-freeze (basically straight water, for the summer, or if you're in a climate which never comes close to freezing even all year around), which will give you a higher heat capacity, allowing the coolant to stay cooler while radiating the same amount of heat.[/QUOTE

thats not correct, less antifreeze means the water boils at a lower temp and becomes steam and then the cooling is dramatically decreased. I have my doubts about water wetter as well, but I haven't used it.

G8rboy

I have not heard a lot of good things about Water Wetter myself. Many of the Miata guys I've talked to have regretted using it after finding an oily sludge building up in the overflow reservoir and the under the radiator cap, on top of it making almost no difference above and beyond a high quality coolant (when used with the appropriate ratio of water depending on season/climate).

shelleys_man_06

The only way to find out is to buy some Water Wetter and see if the Miata guys are right.

ifastfd

Your statement about more antifreeze being better at removing heat is incorrect.

The specific heat capacity for pure water is 1 Btu/lb/°F , whereas most ethylene & propylene glycols are around 0.6-0.8. Therefore, running pure water will remove more Btu's/hr for a given mass flow rate & result in a cooler engine. The primary reason for antifreeze is boiling point elevation and freezing point depression, along w/ increasing the lubricity of the coolant & improving seal & water pump bearing life. Most race engines run pure water w/ a lubricity enhancer & surface
tension reducer. This is why most manufacturers recommend a max 50:50 by volume mixture of af & h20,as anything greater will result in overheating.

[QUOTE=azben] :D

azben

I stand by my statement...I never said glycol had a higher cooling rate than water. You make make an assumption of water being the cooling solution when in actuality it would be steam if the car was run for any period of time. Steam is not as efficient hence glycol is added.

mysql101

Antifreeze has poor cooling properties. 100% antifreeze will overheat
your engine. It is also more viscous. Water is the best coolant.
It has high heat capacity and good heat conductivity. Unfortunately,
it freezez at 0C or 32F. Water is very corrosive at higher temperature
to engines that have parts made out of different metals or alloys
(electrolysis).

It is best to use as little antifreeze as required for cold
protection in your area and manufacturers recommendations for
antifreeze's additives.

Mixing antifreeze and water reduces the freezing point and
increases the boiling point of the mixture. If you don't have
enough antifreeze in the mixture, you risk freezing the coolant
(and engine damage) in the winter, and boiling over in the summer.

Water has a very high specific heat capacity, so a given mass of
water can absorb more energy than straight antifreeze (for a given
temperature rise). So the antifreeze/water mix is a more
efficient coolant than antifreeze alone.

There are other cooling approaches, too. Some race engines have
used *pure water* for a coolant. To minimize water boiling and
pump cavitation, their cooling systems have very high relief
pressures (60-90 psi).

Also some engines are designed to run on pure propylene glycol.
The specific heat capacity is less than water, but the boiling
point is much higher (about 370 deg.F).

azben

i'd agree with that, just to lazy to right it all out

wakeech

what???

no, seriously, because of the higher molar head capacity of water, it can move the same amount of heat at a lower tempurature, thus keeping your motor cooler, honest to goodness. i've also never heard of alcohol raising the boiling tempurature of water, as it doesn't desolve into water (it's not suspended in it, is what i mean) and has a point of evaporation obviously excessively lower than water does.

water wetter, or any other coolant additive in that vien works, really really well.

wakeech

going over the posts after that one, i don't know about the side effects of water wetter brand stuff and its side effects specifically, in either a Miata or RX-8 application, but i do know that they science behind it is very sound.

ifastfd

Wrong again, sorry! Not trying to be an a$$ but I'm an automotive engineer & have been doing this stuff for a living for over 20 years & like to help people cut through the internet hype & actually learn something.

Anywho, the conversion of water into steam has a much higher heat transfer coefficient than liquid water & therefore would result in much lower engine temperatures,IF the system were designed to handle the high pressures & handle the moving & condensing of the steam back to liquid. A centrifugal pump does not pump gas (steam) very well. The system is pressurized to prevent the coolant from flashing to steam.

I am making the assumption that the coolant (water,whatever) is the cooling solution because it is. If you have any significant amount of steam in your existing cooling system, it will quickly overheat

azben

are you sure you aren't trying to be an a$$? read my statements and the others posted carefully ifastfd, misunderstanding on your part. I said cooling is decreased dramatically, and it would be if you only used water in your car (wakeech suggested putting water in the car so that is the premise my comments are based on) for the reasons you stated. The pump wouldn't cycle it well if at all, you would be a condenser/evap setup, etc.

my second statement said "would be steam if the car was run for any period of time. Steam is not as efficient hence glycol is added." Notice the context "if the car" preceding most of that statement.