Didnt know what to label the title. Basically I live in Canada, cars dont have the same engine as you guys get down there in the USA.

I need a rad cap for my dual core half sized all aluminum radiator, and I would like to have it tomorrow so I need to buy local.

What car/engine/type would I tell my local parts store that I need a rad cap for??

I searched but couldnt find any info. I know Ive went and bought the wrong cap before, and got the current one offline but Id love to not have to resort to that this time.

Thanks for any help

 

1997 honda civic EX

 

that is, assuming its an OEM replacement and not a aftermarket koyo or mishimoto big rad

 

Well its an all aluminum so its not a replacement rad for anything... I just remember having cap problems before so Im hoping I can order the right one

 

I would personally get a higher pressure cap. Higher cooling system pressure (it's not a huge jump in pressure) means the water in the coolant will boil at a much higher temperature than your car should run.

This means slightly cooler temps and a better performing cooling system

Also, have you looked into a low temp (170-180* F) thermostat as well as fan switch? This will also help your car run a lower and much more stable temperature

 

I wouldn't run the system any higher then 14-16psi, otherwise your liable to blow out gaskets or o-rings around the water pump and coolant tubes. Plus I honestly dont think the water pump or the amount of heat output alone can generate anymore pressure then that so its really not necessary.

 

I thought that the stock thermostats were already in the 170-180* range? Have I missed something?

Also, increasing the radiator cap pressure only gains you 2-3* per psi. The boiling point is also determined by the ratio of the radiator fluid. (Water / antifreeze)

 

my mishimoto radiator used the same cap as like a 94 prelude.

 

Stocj rad cap is 0.9bar or 13psi, Most aftermarket radiators for civics/integras come with a 1.3bar cap which is 19.11psi.. thats about as high as i would go, at least on a stock mechanically driven pump

At 0.9 water boils at 210 degrees F, or where a lot of boosted Hondas will reach occasionally. At 19-20 it boils at 225-228 degrees F. So you can see how advantageous the higher pressure cap is, because with a stock cap when you get to the 200 degree area the water will start turning to vapor, no good especially on an inline 4 with no vapor vent tube.

I've seen cooling system pressures in the 32psi range on most big money race cars, using external electric pumps, braided/aluminum rad hoses, etc. At that point water won't boil until 254+ but on those cars it's needed do to operating conditons

What creates pressure isn't the pump but from the coolant expanding as it heats up... theoretically you could run as high of a pressure as you could, if the components are up to the task. However 20 psi is what most motors run IF they have an aftermarket radiator and its something I would suggest, especially on a boosted motor. The last thing you want is to boil off coolant and vapor lock the cooling system

And i meant a 140-160 degree thermostat, stock is 172 but the stock fan switch is set much higher at 220..

140-160* thermostat plus a stock b20 fan switch (180 vs 220 for other b series) and a high pressure (1.35bar minimum) and you've got a pretty good system.

However most ecu tuning programs/standalones allow for fan control regardless of temperature.

Mishimoto makes a nice thermostat that opens at 140 degrees F but it's expensive... I know there's got to be some generic 140 degree thermostat that fits b series motors

 

Stock thermo is 172.something lol, I meant 160 or lower

And yea the ratio is determined by the mixture but looking at the base boiling point of water gives you a good idea about the absolute ,minimum point that cool at will start to boil

Now a b20 fan switch is made to grounds out at 180 thus cutting on the fan (at least from what I have been told... keyword told) vs. The b16/b18 switch set at 220. So that's a good deal right there and should keep most cars within the 180-190 optimal power making sweet spot.

Although I am curious to find the lowest temperature fan switch that will simply thread into our motors


I was looking at radiator caps and found this about the one Cusco makes

Pulled from description on inline four.com

"Cusco's high pressure radiator caps high pressure radiator caps work at 1.3kg/cm2 at zero atmospheric pressure. In practice though, the atmospheric pressure of the road surface (approximately 1.0kg/cm2) is added and the pressure is 2.3kg/cm2. "

Although that makes no sense, right? The top of the cap still says 1.3. And since they are all made the same way, wouldn't that be true of all aftermarket caps?

Guess someone needs to buy one and test the true opening pressure

 

I will definetely get a 1.3 bar cap offline since they dont sell that local, is there a specific car I should buy it for offline?

I would definetely also like the lower temp ECT switch FOR SURE!!! I can not find any info at all on the switch though, Im not going to find a b20 in a yard so Ill have to buy it new, is there a specific year b20 or part number?

Any verification it turns the fan on @ 180?

 

Doesn't really matter since you have an aftermarket radiator

Goto www.inlinefour.com go under engine and look at cooling. The rad cap descriptions tell you what style of cap you need

 

Well the prestone one that Im currently running is a Type B going by the pictures. but would that mean a type A wouldnt fit the neck? Ive never tried a type A I guess I just tried this typeB style before and it fit.

Would a type A be any different? Ive always thought it didnt feel solid.

They sell thermostatit fan switches aparently aswell for about $40, but they require a plug, my car just has 2 wires individually going to the back of the ect, how could I make that work?

Or could I possibly have my switch wired backwards and the wires put on the wrong make connection on the stock sensor? Or would that not affect anything

 

any info on the b20 ect turning on @ 180*?

 

I dont know about the ECT switch, i typically do that kind of stuff with my tuner. But i do know that the OEM b20 thermostat is a 180*.

 

Well I realized you guys have access to a great ammount of aftermarket fan switched with your obd1 motors and thermostat housing mounted switches.

On an OBD0 my switch is located on the back of the block and has 2 prongs. This is literally the only sensor on ebay I could find that was my 2 prong style, and not an aftermarket stock temp replacement.

http://www.ebay.com/itm/310544250568...84.m1423.l2649

It is listed as 181-171 on/off, but that seems a little low. I asked the seller to verify the specs and if they have any other models. I would love a 190/180 on/off

What do you guys think?

 

Glad I ran into this topic. I'm in the middle of upgrading all kinds of stuff and the radiator/cooling area is one of them. This thread lead me to google and came across this...

http://www.tuneruniversity.com/blog/...the-advantage/

What I can gather, stick with OEM/Stock unless you're racing. Right?

 

I guess I'll try and find a type B somewhere online, cant find/trust anything local

 

For anyone searching in the future.

An OEM replacement radiator cap for a Subura Impreza 02-07 works and fits perfectly. Its factory 16lbs and under $10 bucks.

For anyone that needs a Type F rad cap like myself.

Solid find