Best Cooling Modifications?

[boyou2]

Originally Posted by Chaluska

if your system has been bled, there shouldn't be anyway any air can get back into the system, i don't understand where you guys are getting that info from. If you are low on coolant.... very low, or have a leaking head gasket, i dont see how air can magically form in the radiator system...

swirl pots / surge tanks are intended for fuel systems, to keep a constant amount of fuel availible for the engine... Thats it...

unless you like wasting money and time on something that is useless...

If i remember, water is made from hydrogen AND oxygen.

What causes air in coolant system, is cavitation from the water pump, and from temperature (you know that water is boiling from about 100°C, and a little more under pressure)

as long as you have water, OR a mix of water and anti-freeze, there will be air in the cooling system

don't forget to use demineralized water to prevent of rust.

[rb25_s13*CHUKI]

Koyo
New OEM water pump
Bled system
Circuit sports aluminum resevior
Aluminum shroud for 2 12" inch fans
No thermostat
Watter wetter+water+half a cup of coolant

=Never ever ever ever overheat! just like me!

[dwnshft2drft]

I used distilled water, less boils means less air

[codyace]

Originally Posted by thefro526

Also, on some engines (Not any Nissan Engine I've encountered though) there's no bleeder valve (1JZ's for sure) or any other easy way to bleed coolant other than doing the funnel/upside down bottle to radiator cap method - which I'm not particularly fond of. A breather tank is just extra insurance and makes the bleeding process easier.

If you look on the coolant outlet, you'll see a little 10mm screw...that's the bleeder valve. I personally don't think it works very well, but some swear by it.


My personal method though is just fill the radiator up, let it fill in...fill it up again etc etc etc until the level doesn't go down. Then I put the cap on and squeeze the upper hose like an udder to form a suction to back fill the head/block. To me it's a failproof way.

[MyblackS13]

My personal method though is just fill the radiator up, let it fill in...fill it up again etc etc etc until the level doesn't go down. Then I put the cap on and squeeze the upper hose like an udder to form a suction to back fill the head/block. To me it's a failproof way.

^ What he said, it works in my 240, sometimes I go do something else while the radiator cap is off and let is sit for a little while too to make sure its all out. Before I had my C&R set-up, I had a fairly thick copper and brass replacement radiator (no plastic) from a local shop with a stock SR clutch fan, no shroud, no under panels, my intercooler opening on my bumper is huge which probably helped some, but my car never even came close to overheating and I've never seen the gauge past half way. Keep in mind, my car is primary used for back road twisties and occasional auto-x and even more rarely driven to work, but it has been in a few traffic jams in the summertime.

Most of the stuff I'm reading seems way over complicated unless you're going to be tracking your car or drifting competitively. Not really necessary for a sometimes spirited, street driven car.

And I have no idea why so many people are so in love with the clutch fan, yes, they work and they work well, but most of us spend so much money for a few HP here and there to get the most gain possible, why lose any of it to parasitic loss like a clutch fan? I'm sure the actual HP drain is minimal but when I took mine off, it was like the difference between the stock flywheel and the light weight one all over again.

[pony5oh]

Hmmm...Great Info Guys!
Yeah, in my case I am thinking that there is something wrong....or I have a big ole air bubble in the system.
I was told that simply raising the nose of the car up, taking the radiator cap off...will allow most all air bubbles to come top the surface?
The radiator is a basic EPray unit...but the build and quality seems great.

Ill post up after we see if that works or not.

What are people using for underpanels? Bulk aluminum and cut it to fit?

[JSimpson]

Water wetter does make a difference if you use enough. But if all else fails, vmount FTW

[thefro526]

Originally Posted by codyace

If you look on the coolant outlet, you'll see a little 10mm screw...that's the bleeder valve. I personally don't think it works very well, but some swear by it.

I'm aware of the bleeder valve but my previous wording may not have came across like that... Lol.

I was just trying to say that a Coolant Breather is a $60 Part that does something - whether or not it makes a difference could be debated, but it's not like someones going and blowing a stack on some snake oil cure.

Also, your method would require patience... I don't have any.

[DrIvEsldEwAyS]

koyo
mishimoto thermo
single 12 inch fan wired to ignition

never had a problem. this is in a ~500whp car in south carolina summers

[Matt191]

Alright you guys keep talking about the lower shroud, is that the thing that sits under the front of the car between the Radi & the engine. Also what is the best temp my SR should run at? I have a DIF fan controller but I'm not sure what temperature to set it at.

[Matej]

Originally Posted by rb25_s13*CHUKI

Koyo
New OEM water pump
Bled system
Circuit sports aluminum resevior
Aluminum shroud for 2 12" inch fans
No thermostat
Watter wetter+water+half a cup of coolant

=Never ever ever ever overheat! just like me!

What are the advantages and disadvantages to having no thermostat?

I have been meaning to replace mine. Never knew not having one was an option.
Is there a catch? Otherwise I do not see why more people would not run without it.

[!Zar!]

No thermostat is a horrible idea. It doesn't allow the cooling system to operate properly.

Even people that do run no thermostat, they have something in its place to restrict flow.

Flowing too fast doesn't allow the radiator to dissipate the heat.

And to the person asking about under trays, the cars come stock with them, it's just that most fall off or are removed and not put back on.

[foxystyle]

^^ I ran with out a thermostat, I saw that it was just a pest always replacing it. I rath have coolant constently running through. It never over heat after. But it is more of a temporary fix as in seasonal, I had it like that during the summer, once temps dropped I threw in a thermostat.

I miss 1990 when this car never overheated and took me from la to sf with no problems. Now my transmission smokes on the 10 freeway, and leaks everywhere.

[Matej]

Originally Posted by !Zar!

No thermostat is a horrible idea. It doesn't allow the cooling system to operate properly.

Even people that do run no thermostat, they have something in its place to restrict flow.

Flowing too fast doesn't allow the radiator to dissipate the heat.

Thank you for the information. I will go with the Nismo one.

[Matt191]

Alright thanks I will keep that in mind should probably buy one for my 240 huh? and Courtesy probably will have one won't they?

[codyace]

Originally Posted by thefro526

I'm aware of the bleeder valve but my previous wording may not have came across like that... Lol.

I was just trying to say that a Coolant Breather is a $60 Part that does something - whether or not it makes a difference could be debated, but it's not like someones going and blowing a stack on some snake oil cure.

Also, your method would require patience... I don't have any.

Ah, I did misread you. FWIW in the thread, I personally am not a firm believer in the swirl pots or breather tanks or any of that nonsense, regardless of HP or usage of cars. I guess it looks cool to some, but if a stock system works...what's teh point?

Originally Posted by !Zar!

No thermostat is a horrible idea. It doesn't allow the cooling system to operate properly.

Even people that do run no thermostat, they have something in its place to restrict flow.

Flowing too fast doesn't allow the radiator to dissipate the heat.

I've always been under the impression that there is no such thing as 'too fast' of flow in regard to a heat exchange system (I'll also put Air to Water intercoolers and their heat exchanger in this discussion as well). The faster you can trasnfer coolant/water in a system, the quicker it will cool the ENTIRE system, thus keeping it cooler in general.

However in our situation, there is the presence of 2 things: a thermostat, and a bypass.

When you turn the car on, the thermo is closed, and the cooling system circulates through itself, helping to speed up the warming of the engine, bringing it up to temperature faster. Once you reach the temperature of operation, the thermostat opens, and now allows coolant to pump through the radiator to cool (while still pumping some through the bypass, albiet marginal) The thermostat here works like a regulator of sorts, keeping the engine at it's proper temperature, and preventing the engine from over pumping through itself without pumping through the thermostat. So while many say 'oh it overflows water and then it can't cool' isn't true at all...what it does is disrupt flow, causing the system to not flow properly...which then causes it heat up, and cause (eventually) a runaway condition. Now if there wasn't a bypass routed into our system, and you wanted maximum cooling ability, it would be fine (although that would only apply to a track car IMO...)


With that said, by removing the thermostat the system end sup flowing at max rate it will not allow the engine to 'maintain' a constant temperature, nor will it allow the engine to operate in it's proper operating range. In regard to restriction being needed, I don't believe that either...as the rad cap's ability to maintain pressure should prevent any sort of air being built up by no restriction.

Originally Posted by Matej

Thank you for the information. I will go with the Nismo one.

Nismo one is NOT a good idea for a street car. OEM is best, you want to have temp up to 180* so the ECU is not changing the timing (as it thinks the car is warming up)



Cliffs for the thread:
-No thermo will keep it cold, but it will eventually overheat and not cool back down.

-Thermostat allows cooling system to flow properly

-Thermostat allows proper operating temps

-Overcooling an engine through lower thermo stat is unnecessary for our cars in a street setup (some cars out there can benefit from one, but not ours)as you want it to get to closed loop/operating temp and stay there as fast as possible.

[Simon1]

Originally Posted by pony5oh

Yeah, I am going to bleed the cooling system next time I get a chance...just to make sure.

What have people done as far as ducting to get fresh air to the radiator?
Are there any scoops or vents that can make the hole a bit "prettier" if I decide to cut some vents in my front bumper?

First of all you should concentrate on the radiator.
If we face the problem of the radiator then we can easily save from the problem of the cooling that is really important to tackle the problem of the cooling.
norwalk personal trainer

[cdlong]

Originally Posted by boyou2

If i remember, water is made from hydrogen AND oxygen.

What causes air in coolant system, is cavitation from the water pump, and from temperature (you know that water is boiling from about 100°C, and a little more under pressure)

as long as you have water, OR a mix of water and anti-freeze, there will be air in the cooling system

Cavitation and vapor from boiling water isn't air, it's water vapor. Cavitation is localized boiling when the pressure drops to a point that the boiling point drops below the current temp (Ideal gas law and all, as pressure drops, so does the boiling point). The bubbles are water vapor and as soon as the local pressure around the bubble (i.e., it's not behind the water pump blade anymore) goes back to normal, it recondenses back into water.

Separating water into hydrogen and oxygen requires electrolysis or thermolysis, neither of which are possible inside an automobile engine. Even if it did, they like each other so much, it would recombine back into water pretty quickly.

[chiboy002]

Originally Posted by Matej

Thank you for the information. I will go with the Nismo one.

no, matej
the nismo one is has too cool of an opening point for a street car. your cooling system wont be at the right temp which is also pretty bad for the engine

just stick with oem nissan, it opens at a proper temp. It works on track/street so no worries there

[Matej]

Thank you for the advice, OEM it is then.

[Pandapants]

Originally Posted by Chaluska

if your system has been bled, there shouldn't be anyway any air can get back into the system, i don't understand where you guys are getting that info from. If you are low on coolant.... very low, or have a leaking head gasket, i dont see how air can magically form in the radiator system...

swirl pots / surge tanks are intended for fuel systems, to keep a constant amount of fuel availible for the engine... Thats it...

unless you like wasting money and time on something that is useless...

iirc, vapor bubbles form from hot spots in your motor, effectively decreasing the cooling efficiency of water and/or coolant. Coolant breather tanks and swirl pots are suppose to remedy this issue by continuously swirling the water/coolant.

[XxHybridx]

thought this was a pretty good thread so im bumping it back. I have a question, after an accident my car didn't run for about a 11 months. fixed the car and just had to replace the radiator after the accident. now of course air got into the cooling system, and car ran fine for a whole day then it started heating up towards end of day. so i figured there was air in the system, i got the air out and the temp problems went away.

Now a few days later my temp spiked up for about 5 seconds then it went back down and it hasn't done it since then. car has been running fine now.

Running no electric fans since the stock one got chewed up by the clutch fan. All im running is clutch fan now (brand new one). will not running that tiny electric fan really make a difference. just wondering why my temp spiked up for a second.


oh, and my damn bleeder valve is broken.

[fliprayzin240sx]

Electric fan just turns on with the AC on...helps cool the AC condenser more than anything else.

[cdlong]

It also turns on when the ECU reads coolant temps of more than 192 degrees. Or something, I just pulled that number out of my ass, it's in the FSM though. But yeah, I wouldn't bother. You probably just have another air bubble.

[stilmissmysti]

Originally Posted by boyou2

If i remember, water is made from hydrogen AND oxygen.

What causes air in coolant system, is cavitation from the water pump, and from temperature (you know that water is boiling from about 100°C, and a little more under pressure)

as long as you have water, OR a mix of water and anti-freeze, there will be air in the cooling system

don't forget to use demineralized water to prevent of rust.

you use demin water to prevent scale not rust, rust comes from oxidation not minerals

[S-Nation S13]

such a great debate over e-fans,clutch fans..choose what you want.. just make sure your coolant system if bleed..and youll be ok

[Imarvin240]

as for what Codyace said, I completely agree that flow is one of the most important things when cooling an engine. I am currently in the middle of doing a liquid to air intercooler system and I am also not running the factory water pump on the engine. I am running an electronic water pump with a controller that will be in car so I can change the flow rate and on/off temperature for when the car is on the track, street, warm up, ect. By doing that, I also get rid of the factory pump and just put a plate over it, creating less resistence on the engine and the coolant traveling behind the plate. There are a few companies that make a "good" kit and they aren't even that much money. but like everyone has said, in the end you have to bleed the system properly.

[jamg]

Originally Posted by CrimsonRockett

Surprised no one has thrown this up.

really cool mod.

i had an idea to put ducts behind where the bumper was, and direct it to the areas needed, but i never got a good idea of how i would do it.

this helps a lot. hopefully i'll be able to use some sort of other material other than that and it efficiently cool my car just as well.

[pacotaco345]

Sorry for the bump but I've read through this thread before and I'm getting ready to drive back home from TX to CA for summer break. I (obviously) had no heating issues during the drive to and from for winter break, car stayed below 180* for the most part, and the first time I drove out at the beginning of the school year the hottest it got outside was 80* and for the most part my water temps were low 190*. If I wasn't planning on ditching the ka for an sr next month I'd get a bigger radiator but for now I'm running:
OEM plastic rad
mishi 140* thermostat
Altima fans (come on at 185* shut off at 175*)
100% distilled with a bottle of water wetter

I went on an hour ish long drive over the weekend when it was about 80* out and my car was hitting mid 190s, on the freeway, doing 70, not uphill. However as soon as I get off the freeway and sit at a light my temps drop to ~170* within the minute of me sitting stopped. This is kinda concerning me. The only difference between this setup and the previous one (last summer) is that now I have a W9 bumper instead of the OEM chuki one, which doesn't have that plastic lower shroud that goes all the way back to the core support.

Anyways, I guess my questions are 1) What are your guys' operating temps with stock radiators and 2) Should I make up some sort of lower shroud? I was thinking just some cardboard or balsa wood would work for the time being...

[BlackZenkiS14]

What is the best aftermarket under tray to aid in cooling? And have some level of protection as well?