Landracing Forum
Tech Information => Technical Discussion => Topic started by: biglady112 on November 24, 2015, 11:00:32 PM
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I have been looking at a lot of cars lately(mostly drag cars) and have been seeing an awful lot of cars not running radiators and just running surge/reserve tanks. I helped with a blown door slammer for a long time and after it was recommended to us to up our coolant capacity we stopped losing head gaskets. It worked so well it inspired me to run a large surge tank on my street driven rat rod with success.
It got the wheels turning and we are going to be addressing and updating our cooling system in our standing mile car. It is a blown four cylinder car with an iron block. If anything we will at a minimum be moving to an aluminum radiator with AN fittings and hoses. As I was looking around for ideas I started noticing that a lot of serious cars like streamliners, lakesters, competition coupes and the like don't seem to be running radiators. That is unless they are hidden, laid flat under the car, in the trunk or just not in the pictures. Two quick and famous car come to mind where I don't flat out see radiators are the Blowfish and the Speed Demon. I have also noticed on some lakesters that radiators are not standing out to me.
I can only imagine that by adding capacity to both the salt flat door slammer I was helping with and on my own vehicle that it could work with enough water on a standing mile car. The only two things that are somewhat unique is we are a 1000hp, blown, iron block four cylinder. I still can't help but think that with the right amount of water that 5,000ft is not going to be too much time under load that running straight water from a reserve tank will not heat up too far without a heat exchanger.
What are some folks thoughts and experiences on this potential setup? Have you used no radiator or seen someone using no radiator and done well with it? Maybe someone with a blown car that makes big power? Thanks for your time.
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I run a radiator in a box on my lakester and pump water from another tank through the box. Hooley and Sumner have a good set of picts on there build on how to build it---there are many advantages and options this system gives you. All water to water heat exchangers. and plenty of pressure in the block.
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Most land speed cars, if they are allowed to by the rules, prefer not to run a radiator that exposed to the air because of the additional aero drag.
If you are loosing head gaskets and knocking out valve seats then you possibily need more water pump and you need to run the water system at high pressure, NASCAR runs at 75 psi and I have seen some over 150 psi. The radiator in a box allows you to basically run a standard radiator, which allows you to run high engine system pressure, in a container that carries water that cools the radiator. This allows you make a water container that is not pressurized and also because the radiator is in water the size of the radiator can be much smaller. A water to water heat exchanger is about 7 times more efficient that a water to air unit. The proper design of this type of system requires two water pumps, on to circulate the water through the engine and another to circulate the water with in the "box" through the radiator cooling matrix.
If you have a 1000 hp four banger you are obviously turbocharged and this means that you need a water pump that moves at least 100 gpm (10 gpm/100 horse power) at 40 to 50 psi. There is not an electric powered pump available today that will do that so you need to have an engine driven pump. You can use one of the electric pumps to circulate the water in the box but not the engine.
The other option is to use a water reservoir that can be pressurized to what ever you set your system pressure at and the volume has to be high enough that the amount of heat that the water adsorbs does not boil the water. The high pressure raises the boiling point of water and the high velocity of the water because you are using a big pump will substantially lower the possibilities of steam pockets around the exhaust valves that turbo motors like to make. The other advantage of the pressurized container is that you can fill it with water and ice which greatly increases its' capacity to adsorb heat because of the ability of ice to adsorb more heat when it transitions from a solid to a liquie. If you go with this route the only shape for the reservoir is cylindrical every other shape, square box, oval etc will deform and/or just blow up and if they are strong enough not to deform or blow up they will be very heavy.
The amount of heat that an engine dissipates through the cooling system is about 30 percent of the power that the engine produces. This does not mean that it is 30 percent of 1000 hp, in your case, it is 30 percent of the fuel energy that is used. So take your BSFC (Brake Specific Fuel Consumption, which is in lbs/horse power hour) times the hp times the btu energy per pound of fuel and it is approx 30 percent of that number. You can also take 30 percent of your shaft horse power divided by the estimated thermal efficiency of your engine (40 to 60 percent) and get the approx heat load.
A good cooling system can make an engine such as yours reliable or a poorly designed one can make it a grenade. Have fun and keep us up to date on the car as 1000 hp cars are usually very fast.
Rex
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Our car has substantially less than 1000hp but we run without a radiator. The cooling system has two tanks. A small surge tank and a large reservoir tank, with a valve to bypass the large tank. With this arrangement you can use the short loop to heat the engine quickly and then switch to a much larger volume of coolant. It has worked well for us so far at El Mirage. Basically for your application you'll need some flexibility in how much water you use in your system, but expect to use quite a bit more than if you were running a radiator. We have about 8 gallons for a healthy 1 liter 4cyl, and it rises maybe 10-15 degrees in temp during a run.
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At our last event we were still on a stock radiator and cooling system with two fans. It holds a little less than two gallons. We were using a 50/50 water/coolant mix. This year we will be making the switch to straight water. We were making about 850-875whp for that event and it was a half mile event at an airport. We started all four of our runs at 110-120* coolant temperatures and by the engine of each pass we were in the 170-180 range. We obviously intend to double the distance of racing this coming year. The car was on gasoline this year and will be moving back to Ethanol this coming year and we will be increasing the power to somewhere between 900-1000whp for the coming season.
The owner of the car is really against running no radiator but, I have been on board for some time and really think I can make this work in the name of aero.
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I sure would read -reread-- and read it again -----what Rex has laid out
You need PRESSURE and Volume through your eng to handle that many BTUs---of course the alky will help--- you have been depending on heat sink but with the greater distance you need to be able to remove lots of BTUs
remember also you can remove nearly as many with oil as water. YMMV
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It may be beating a dead horse to you but, to us it is brand new. Or else I would not have made the thread asking for ideas on how to make it work correctly. All I have experience with is running a ten gallon reserve and an eight gallon reserve. Both with a radiator. So it is uncharted territory for us. I found pictures but, pictures don't tell the story, issues and successes of a system.
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We currently only run 5qts of oil in the engine. I intend on putting on my spare 8qt pan here in the next few weeks as well. I am not sure if we will be going to any sort of reservoir for the oil as the salt flat car I was helping with did not seem to need more than about 7qts and aside from a radiator I think this setup will be kind of similar.
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Well I will get rid of the horse then!!
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Our car makes north of 2400hp and runs approximately 1 min 20 seconds. With billet heads and block. No turbo's-no water required.
POPS
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Alcohol? Nitrous? What car might this be? Any engine shot pictures? Just trying to wrap my head around what some folks are doing and what is successful for them. Thanks.
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my bet would be NITRO :roll:
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Alcohol 7800 ABFS
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And the 7800 car runs 60 psi boost
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Today we are seeing more dry block/head engines than ever before. They are for the most part fuel engines that I know of and some are blown and others are not.
On lower HP engines an electric pump on an unpressurized non-radiator system can be made to work; it is the way I've done it for years. The best pump I've found is a Maziere and I use return hoses to the tank with a smaller diameter than the supply from the pump. This keeps some "pressure" on the internal of the head and block. I prefer this method and leave the pump on after the run. The total system holds 9 gallons. When I ran over 700HP I had 13 gallons and ran to the 5 mile with out problems....Good Luck.
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Pops said: "Our car makes north of 2400hp and runs approximately 1 min 20 seconds. With billet heads and block. No turbo's-no water required.
POPS"
Try that on gasoline. Fuel cooled engines are gaining popularity and work because of the huge amount of fuel that is driven through them. Danny Thompson, the Nishs, the 911 roadster, and many more run this combination. When you run 30-60 gallons of fuel through the engine per run a pretty large amount is just for cooling especially alcohol.
Rex
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... Any engine shot pictures? Just trying to wrap my head around what some folks are doing and what is successful for them. Thanks.
(http://purplesagetradingpost.com/sumner/Hooley%202013/rad-in-box-76.jpg)
The radiator in a box...
(http://purplesagetradingpost.com/sumner/Hooley%202013/rad-in-box-62.jpg)
... that we are using....
(http://purplesagetradingpost.com/sumner/Hooley%202013/rad-in-box-68.jpg)
No real results as only license runs with one to 218 at 45% throttle. So no heavy loads yet but I feel it is going to be just fine.
We have a 30 gallon main tank that pumps through the rad-in-a-box with a Mezier pump. More on the build here with a lot of pictures ...
http://purplesagetradingpost.com/sumner/Hooley%202013/13%20-%20construction%20menu.html
Sumner
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We agree Rex, No turbo's, No parts washing fluid, No water required.
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I saw that studebaker in 2012 at the Ohio mile and it went 225mph right in front of us. We were one or two cars back from you guys. We had a lot going on and I was not able to ever see if you had any of the body panels off. So I have seen that car twice now and know it makes big boy power. Thank you for the pictures.
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We do it a little different than Sparky. We have our "radiator in a box" and use a small electric pump to spray water over the radiator. We use about 1-2 gallons of water in the box at El Mirage & about 5 gallons or so at Bonneville.
When we were normally aspirated we didn't need to spray water at El Mirage and just added water to the box accordingly. Now that we are turbocharged we spray at both places.
Works for us. 8-)
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Here is where the radiator in a box sits on the right side in the chassis. The box is vented outside the car. The blue cap is where we add water to the box. On the side we can remove the line that sprays water on the radiator and pump the hot water out after a pass if we need to and refill it with cool water for another run.
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Mike, What is the temp that you run your engine at? My guess is some where close to what ever the boiling point of water is at the altitude you are running at.
Using the "latent heat of evaporization" means that what is cooling Mike's engine is the energy required to change the water that he sprays on his radiator into steam, which in the case of water is about 970 btu/lb. So if he is spraying two gallons of water, weights about 6.7 lb/ gallon then he is dissipating about 13,000 btus on his El Mo runs and 33,000 btu(s) at Bonneville, this combined with the the thermal inertia of the engine water and the radiator provides more than sufficient heat rejection. I think that IO (Interested Observer) at one time suggested this method. Obviously it works. This also works for the alcohol fueled engine as the latent heat of evaporization for methanol is 470 btu/lb and if you look at spraying 30 gallons through the engine then the reason that they can live with out water jackets begins to become obvious.
Rex
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On our roadster we run a belt driven meizere water pump, 110 gpm at 50-55psi in the block and heads.
We did extensive static flow testing with the block, head gaskets, heads, and valley cover return system to balance
the water flow.
This is all fed with an 18 gallon water tank, and a small aluminum radiator on the return side.
Works great at Bonneville, at El Mirage water temps are to low and only go up a couple of degrees in a 1 1/3 dirt pass.
We have about the same HP but twice as many pistons.
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Mike, do you use the hot water to clean your chute like we did?
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Any pictures spdracr? The high pressure has me intrigued.