For a car that sees track time, specifically road race time, it would be a good cheap upgrade to your cooling system. By increasing the radiator cap to 1.8, the radiator can handle 25.6 psi, while a 2.0 cap ups the ante to 28.45 pounds. So, the TRD cap, a higher pressure cap, will help increase the boiling point of your coolant just a little bit more. As the coolant gets hot it expands creating pressure in the system. If the cap that you are using for your radiator is not sufficient, it can result in problems with your cooling system. With you running a mild small block, relatively light car, new aluminum radiator, IF you run into overheating issues, you will be looking for another problem. A 50/50 mixture as we typically use actually gives us a freezing point of -35 degrees Fahrenheit and a boiling point of 223. So if some extra pressure is good, why not a lot? 2. A system with 15 psi cap will add 45 degrees for a final boiling point of 268 degrees. In this case, the coolant is more likely to be lost to boiling off than by simple evaporation. The radiator cap acts as a release valve set to open at the maximum pressure point. They will prevent excessive pressure. There is one coolant cap that is quite different others: Stant #10231. What these caps can be used to do, is run  less antifreeze and more distilled water in your cooling system in the summer. The radiator cap is designed to allow access to fluids in a ‘closed' system. In particularly hot areas with engines that are running high compression or boost, a 1.3 bar radiator cap, water wetter and a reasonable coolant ratio or distilled water setup would be a good "stock upgrade" to help prevent detonation. It also has a relatively low boiling point at 212 degrees Fahrenheit. Straight water has a boiling point of 212 degrees. A calibrated pressure-relief valve is usually incorporated in the radiator's fill cap. The radiator cap controls this expansion and provides constant pressure on the system. The cap acts as a pressure relief valve. I would never pay more than maybe $40 and really, you can get just about any old 1.3 bar cap that fits for around $10 that will do the job just fine.If an OEM tuning house sells one for your car, you may want to go with that one - the cap is simple but it's extremely important it functions properly. While the pressure cap trick gives us a higher boiling point, it does not a thing for freezing point. Higher cap ratings does NOT increase the pressure on the system per se. How much does the pressure raise the boiling point? Low Temp Thermostats: What's the Advantage? The cap does this by a spring loaded valve which serves as a pressure relief valve at a rated pressure. Für nähere Informationen zur Nutzung Ihrer Daten lesen Sie bitte unsere Datenschutzerklärung und Cookie-Richtlinie. The coolant used to cool the engine does so at maximum efficiency when kept at specific pressure. Get all of the above courses (many of which not currently available anywhere else) for one single price of just $309.75 $69.95. Damit Verizon Media und unsere Partner Ihre personenbezogenen Daten verarbeiten können, wählen Sie bitte 'Ich stimme zu.' While we'd love to run 100% distilled water in the cooling system, we can't because of corrosion and boiling/freezing points. Therefore, by using a 1.1 bar cap we make the average boiling point of a stock cooling system somewhere closer to  around 257-260 degrees. In an ideal world, engines would be cooled by straight water with no antifreeze added. But, back to the radiator cap. i personally have had my bike up to 230* with watter wetter and no coolant. Remember that a 50/50 ratio of coolant has a boiling point of 223 degrees. It can also cause water pump failures amongst other damage via a process called cavitation. Check your owner's manual for proper cap replacement. - Engine Tuning Secrets with Ben Strader of EFI University (MP3 and Transcript) - $69.95 value. By upping our cooling system pressure to 1.3 bar we gain about 8.7 degrees. The conversion factor is 1.02, so for the purposes of this article, because kg/cm2 is more awkward to write, I will say 1.1 bar and 1.3 bar. And the boiling point increases 2-3 degrees for each additional psi of pressure in the system. Installing one won't hurt anything. Am using a 160 degree thermostat with a cooler fan switch, so don't need the higher pressure cap to prevent coolant boiling. The cap is actually a pressure release valve, and on cars it is usually set to 15 psi. Where to Find the Pressure Rating It plays an integral part of the system by removing … You'll notice that there's a plunger on the bottom of the cap. However, I'd still run 50/50 in the winter. Restrictors have been used extensively in racing as a means to increase the pressure in the engine and prevent the radiator cap from blowing off. Pressure caps raise the boiling point of water and antifreeze inside the cooling system. Higher coolant pressures also transfer heat from the cylinder heads more efficiently. Dies geschieht in Ihren Datenschutzeinstellungen. The same way a pressure cooker increases the boiling temperature of water. Due to this, altitude determines boiling point. If you ever do approach boiling point, they'll give you a little more insurance against it, and they'll keep the coolant doing its job longer before the bubbles in the fluid create problems. for the track. In closing, if you want to run the same setup all year round and want to be extra safe, run 50/50 antifreeze with Water Wetter (it improves coolant efficiency and especially helps evenly cool the cylinder head), add a 1.3 bar cap for good measure. When you add antifreeze to water, the ability to cool evenly and quickly drops. Under normal operating conditions, with everything else untouched it gives you a small amount of extra protection against localized boiling and therefore hot spots in the cylinder walls and cylinder head. When working properly, the cap provides a tight seal that … 10361 (19-21 pounds), 10362 (22-24 pounds), 10363 (28-32 pounds) Mini Race cap, all include upper gasket for use on open and closed cooling systems. So, yes, I realize import caps are rated in the metric unit, but I'm going to use bar instead to make my writing a little easier. More importantly, pressure and a high flow water pump … Ive got an aluminum BeCool Radiator in a 72 Nova...The recommended pressure cap to use is between 12-13 psi radiator cap....What would happen if I put a higher pressure cap on the radiator like 17 psi...Would it cause any engine damage or anything, Add another $10 for a bottle of water wetter as well. If you have a 7lb cap and you are puking.....then try a 12lb. Boiling is bad for a number of reasons which I won't get too into here, but, steam/bubbles in coolant actually insulate coolant from the combustion chamber and would render the coolant useless at cooling the hot engine. Besides that, up until about 60% coolant, you do gain boiling point and freezing point. Most radiator pressure caps keep the system pressure at 16 PSI so the engine coolant can get considerably hotter without the fear that it will boil off. The other benefit is that straight water as we discussed before is the most efficient cooling fluid. Caps have a seal that can wear away over time. The radiator cap comes in different pressures. The radiator cap is designed to be the weak point in your cooling system so it can safely vent pressure, you don't want to use a cap that is so resistant to venting pressure that it causes some other part of the system to become the weak point. Usually this is set at a density of 15 pounds per square inch (psi). Other than that, it's a nice shiny object. However, past 60% coolant to water, you start to go the other way again, sharply. Well, it may seem obvious, but the cooling system on your car is rated to a certain pressure. The benefit on the track being two-fold. OK, if radiator-cap pressure is say 20-pounds as opposed to 18-pounds, won't the overall impact on the engine and cooling-system be more heat/pressure stress??? Well, let's not forget the freezing point. We recommend using a radiator cap with the highest pressure rating that the radiator is designed to accept. We also don't want to use 100% antifreeze because it would be a poor cooling fluid. However, water has a few properties that make it imperfect as an automotive coolant. The radiator cap allows pressure to build up in the cooling system and will eventually vent that pressure to the overflow bottle as the need arises. you are not boiling over are you? Some tracks do not allow you to use antifreeze as it is literally slick as snot if it leaks or spews onto the track. A word of caution: Run a high-pressure radiator cap of up to the max pressure recommended by the manufacturer of the radiator. However, when mixed with a slight change in coolant, these caps can actually add quite a bit of cooling efficiency to your car, especially for hot summer track days. The cap falls outside the 1-2 PSI tolerance in holding pressure. It closes again when the pressure has dropped to the desired level. (2) By keeping pressure on the cooling system, it raises the boiling point. (4) As the system cools down, it allows coolant to return to the engine from the expansion recovery tank. Antifreeze only adds 11 degrees to our boiling point, so the main reason for running a 1.3 bar cap is to run straight distilled water (with water wetter to prevent corrosion) or a significantly reduced antifreeze ratio without danger of boiling over. They are a small amount of insurance against possible overheating, especially for tracked cars or for excessive idling in the hot summer months. (3) The radiator cap allows coolant to go to the expansion recovery tank when coolant gets hot, expands, and pressures increase. Spoon, Mugen, TRD, and about two dozen other 'big name' companies all sell these "High Pressure" radiator caps. Radiator Caps As the engine's coolant heats, it expands, increasing pressure inside the closed coolant system. No BS Information for Daily Driven Performance Enthusiasts. Radiator caps are the most overlooked component of your cooling system and ironically the least expenseive. The radiator cap sits on top of the radiator and contains a spring-loaded plunger. Water is corrosive and it will gradually eat away at seals and cause metal inside your engine to deteriorate. That same mix at 16 pounds per square inch (psi) of pressure boils at approximately 250 degrees. And over time your fuel costs will also increase. (Coolant freezing points...The point of the ethelyne glycol (or whatever it's made of) in coolant is to really help the water it's cut with. Cooling system pressures are controlled by … needle on pump immediately returns to zero. These caps look cool, and they're sold by big names - but let's look at what they actually do and why you may or may not want one. If your area doesn't get down to negative temperatures in the winter, you can run a decreased ratio of antifreeze to coolant if you like all year round. Take TU Premium for a test drive for a month for just a buck and stop listening to wannabe gurus and get it straight from the experts. Antifreeze both keeps water from freezing in the winter (by lowering the freezing point of the water) and at the same time raises the boiling point of the water. It is hard to believe that a simple part like a radiator cap can actually push the coolant’s boiling point up by about 45°F (25°C). A bad radiator cap cannot effectively seal off the system; nor keep it properly pressurized which will compromise the proper functioning of the cooling system.. The hotter things get, the more pressure created. The heart of any cooling system is the radiator. So, we generally add antifreeze to distilled water to create the coolant we run in the car. Sure, the boiling-point will be raised with the higher pressure cap....but so will the pressure in the cooling-system. Take TU Premium for a test drive for a month for just a buck and stop listening to wannabe gurus and get it straight from the experts. The cap does this by a spring loaded valve which serves as a pressure relief valve at a rated pressure. Well, it's about 2-3 degrees for every psi that we increase the pressure of the system. So why not run it this way all the time? Pressure actually increases the boiling point of a fluid as you may know from high school physics class. Vented Radiator Panel: Good in Theory, But in Practice? However, if you ask the average person what they actually do, you'll be met with cricket chirps. So the over-simplified answer to the tech quiz is that, yes, a higher pressure radiator cap can help prevent overheating. A standard 1.1 bar cap adds 48 degrees to the boiling point of either fluid. "Radiator Caps In a cooling system, a higher pressure equates to a higher boiling point for the coolant. Yahoo ist Teil von Verizon Media. Replacing your radiator cap regularly can save your customer money at the pump and save wear and tear on your cooling sytem overall. Sie können Ihre Einstellungen jederzeit ändern. As the coolant system pressure increases with a rise in temperature, it will reach the point where the pressure relief valve allows excess pressure to escape. Adding the additional 0.2 bar of pressure gives us another 8.7 degrees in both cases. If the radiator cap is stuck, pressure may build inside of the radiator, which could … For one, it has a relatively high freezing temperature at 32 degrees Fahrenheit. This tank is there just to catch the coolant and store it until things cool back down, when a vacuum will be created and most of the coolant will return to the cooling system. When we change from a a 1.1 bar to 1.3 bar cap, we gain 0.2 bar or roughly 2.9psi of pressure. The boiling point of water increases when the water is placed under pressure. Under this pressure, water boils at 257°F. When the fluid pressure inside the radiator exceeds 15 psi, it forces the valve open, allowing heat to escape and excess coolant fluid to overflow into the tanks on either side of the radiator. - Header Design Secrets with John Grudynski (MP3 and transcript) - $69.95 value With the lower pressure, the water pump seals, and water cooler seals have less stress and … 09-11-04 02:06 PM - Post# 511193 In response to RocketRide Okay....one more time. Finally, it isn't a very good lubricant and the water pump and seals in your cooling system rely on other compounds in your coolant to provide those properties. Wir und unsere Partner nutzen Cookies und ähnliche Technik, um Daten auf Ihrem Gerät zu speichern und/oder darauf zuzugreifen, für folgende Zwecke: um personalisierte Werbung und Inhalte zu zeigen, zur Messung von Anzeigen und Inhalten, um mehr über die Zielgruppe zu erfahren sowie für die Entwicklung von Produkten. also the higher pressure caps not gonna lower temps, it will just raise the boiling point. These caps are also available for domestics and some exotics as well, but the same principle applies regardless of the make/model of car. As pressure builds, it pushes up on that valve until eventually the valve is opened far enough for coolant to flow out of the tube connected at the radiator fill neck. Both however are boosted significantly by the pressure in the system. - Dirty Secrets of Oil with Ryan Stark (MP3 and transcript) - $69.95 value VENTED Radiator CAPS. This pressure varies between models, but typically ranges from 4 to 30 psi (30 to 200 kPa). A HUGE package savings. Too much pressure can cause damage, while not enough pressure can cause the engine to overheat. Find out how you can gain access to some of the smartest guys in tuning via TU premium. Most imports use 1.1 kg/cm2 radiator caps while these aftermarket pieces are typically 1.3 kg/cm2. It works the way a pressure cooker raises water’s boiling temperature. Want more in depth tech like this? performance. So, we effectively get 8.7 degrees (or around that) on top of the 257-260 degrees  before we might experience boiling coolant in the system. 1. STANT Racing RADIATOR Caps. 1.1 bar is roughly 15psi, and 1.3 bar is around 18psi. Sometimes they are rated in the "bar" unit. Rated to a higher boiling point increases 2-3 degrees for each additional psi pressure... Caps can be removed to check the coolant mixed in is rated to certain... That is quite different others: Stant # 10231 from the cylinder heads more efficiently word caution... 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Closed cooling systems physics class 1.3 bar we gain about 8.7 degrees in both cases vapor... A cooler fan switch, so do n't need the higher pressure cap prevent! Cold, the boiling-point will be raised with the highest pressure rating the. The water is corrosive and it will gradually eat away at seals and metal. Point at 212 degrees is not a lot fact, 100 % antifreeze because it would a! A poor cooling fluid > but your theory should be reversed cos the pressure. Causing the pressure of the radiator, or to add coolant time, it about! Cars or for excessive idling in the cooling system heats up, it coolant!