OK - This might be a jackass question but after pooring over a ton of pictures I have to ask this; How do cars with out a radiator run? Is there a water tank that the water curculates thru or id the engine run dry? - Wouldn't it overheat?
Some run with water in the block and an expansion tank. Some run dry. Some have the block filled for strength and have no room for water. If you run alcohol, you can run for quite a while because it cools the motor. Drag runs are only a few seconds long for dragsters, and including warmup and staging the time running is less than 3-5 minutes - unless your opponent tries to burn you down. That's why you see guys get in staging wars, and usually see a very pissed driver when it happens. I've seen guys use the frame for water storage on dragsters The flathead that won the oldies class at BG last weekend poured water through the heads and block after each run to cool it. Newer bracket dragsters have small radiators w/fans between the rails because they can't have tow cars. Hope this helps.. Mutt
at the end of the tracks they usually had a water hose to hose the engines off, my dad was on a flathead dragester team in the early 70's and he said at the end of the races they would put the end of the hose into the water inlet thing on the head and just let the water run through it for a couple minutes.
Hey Joe, The simple answer is that most dragsters just aren't running long enough to get "hot". Many drag cars run electric water pumps. Found this stuff on a couple of other sites but it's still some pretty amazing dragster info; * One Top Fuel dragster 500 cubic inch Hemi engine makes more horsepower than the first 4 rows at the Daytona 500. * Under full throttle, a Top Fuel dragster engine consumes 1½ gallons of nitro methane per second; a fully loaded 747 consumes jet fuel at the same rate with 25% less energy being produced. * A stock Dodge 426 Hemi V8 engine cannot produce enough power to drive the dragster's supercharger. * With 3000 CFM of air being rammed in by the supercharger on overdrive, the fuel mixture is compressed into a near-solid form before ignition. Cylinders run on the verge of hydraulic lock at full throttle. * At the stoichiometric 1.7:1 air/fuel mixture for nitro methane the flame front temperature measures 7050 degrees F. * Nitro methane burns yellow. The spectacular white flame seen above the stacks at night is raw burning hydrogen, dissociated from atmospheric water vapor by the searing exhaust gases. * Dual magnetos supply 44 amps to each spark plug. This is the output of an arc welder in each cylinder. * Spark plug electrodes are totally consumed during a pass. After 1/2 way, the engine is dieseling from compression plus the glow of exhaust valves at 1400 degrees F. Cutting the fuel flow can only shut down the engine. * If spark momentarily fails early in the run, unburned nitro builds up in the affected cylinders and then explodes with sufficient force to blow cylinder heads off the block in pieces or split the block in half. * In order to exceed 300 mph in 4.5 seconds dragsters must accelerate at an average of over 4G's. In order to reach 200 mph well before half-track, the launch acceleration approaches 8G's. * Dragsters reach over 300 miles per hour before you have completed reading this sentence. * Top Fuel Engines turn approximately 540 revolutions from light to light! * Including the burnout the engine must only survive 900 revolutions under load. * The redline is actually quite high at 9500 rpm. * The Bottom Line; Assuming all the equipment is paid off, the crew worked for free, and for once NOTHING BLOWS UP, each run costs an estimated $1,000.00 per second. The current Top Fuel dragster elapsed time record is 4.441 seconds for the quarter mile (10/05/03, Tony Schumacher). The top speed record is 333.00 mph (533 km/h) as measured over the last 66' of the run (09/28/03 Doug Kalitta). Putting all of this into perspective: You are riding the average US$250,000 Honda MotoGP bike. Over a mile up the road, a Top Fuel dragster is staged and ready to launch down a quarter mile strip as you pass. You have the advantage of a flying start. You run the RC211V hard up through the gears and blast across the starting line and past the dragster at an honest 200 mph (293 ft/sec). The 'tree' goes green for both of you at that moment. The dragster launches and starts after you. You keep your wrist cranked hard, but you hear an incredibly brutal whine that sears your eardrums and within 3 seconds the dragster catches and passes you. He beats you to the finish line, a quarter mile away from where you just passed him. Think about it, from a standing start, the dragster had spotted you 200 mph and not only caught, but nearly blasted you off the road when he passed you within a mere 1320 foot long race course.
actually, all drag cars run long enough to get 'hot'. when t/f cars pull off, every piece of the engine is smoking hot, but being all aluminum, and the fact that the heads and block are solid billet (no water jackets), they handle the heat very well. t/f cars need lots of heat for the fuel to burn properly at the volume they run. as far as 'regular' dragsters are concerned, there are two varieties and subs. the solid block and water varieties. any car that dont have a tow vehicle or has to make quick turnarounds has to have a radiator and pump. but keeping it on dragsters... on our altered, (sbc, carb on gas, 8.50 @ 160) we run a small aluminum radiator and an electric water pump. theres an overflow line from the expansion area of the filler with a pressure valve to the puke tank. lots of guys use a radiator cap system. if we've got the mild tune up it will go thru the lights around 180, and i can drive it back to the pits. with the killer tune up, it'll go thru at 225 an i hafta kill the motor and keep the cooling system running. either way, we tow back with the cooling system running because you never know how fast you're gonna get called back and working on a hot motor sucks!. most of the bracket guys have they're combos set up to drive to the grocery store and back all day. most guys we run with who run alky, fill the blocks and use solid heads. it'll hold heat well, but it takes a minute to get it up to temp. them alky motors need at least 180 to start getting happy, and most trap at around 225. they shut off in the lights and coast to a halt. the guys who opt to run a closed water system, plumb the engines watering passages with a bib on one end and a spout on the other. after you run, you hook up the hose and run water thru till it runs cool. you dont see much of that anymore.
very good info, some of that stuff i had no clue about. 8 g's thats more than a jet doing a high speed manuver isn't it?
Actually, most modern jets (F-15 Eagle, F-18 Hornet) can pull better than just over 9 G's in high speed manuevers. The pilots wear G-suits with air tubes in the legs and torso. These provide air pressure to the lower extremeties to combat blood pooling in the legs and belly, causing a "blackout". A "redout" is a negative g manuever that causes the blood to rush to the head. No fix for that, other than watching how the pilot manuevers. My other hobby was model aircraft. Can ya tell?
amazing stuff, had a funny car driver tell me once what he has to do in just a number of seconds over the 1/4. That to was amzingto hear!
When a burn down happens in staging, you can usually tell who to have the camera on during the run. An experienced ear can tell when the engine is too hot and will blow during the run. That's why Buster (the old NHRA starter) never put up with staging duels on the fuel cars. If you start your car after the other guy, then do a slow or long burnout and take your time staging while the other guy is getting hotter and hotter, you'll cause the other car to cook off while yours is coming up to optimum heat. He'll either go up in tire smoke overpowering the track, or blow the engine on the run. Chickenshit way to win, but it works.
we ran our dragster with a fairly mild 433 chevy and an alcohol carb,no radiator,water in the block,and a puke tank,and there were times we'd have to pop it off in staging to get the temp where we wanted it prior to the run{usually about 140-150 in staging}usually during qualifying,we'd be okay do to the time alotted between sessions,but during eliminations,aftereach pass,we would open the pepcocks on each side of the block,and let it drain as we towed it back,by the time we got back,packed the chute and ran water thru the block,topped off the fuel,we'd be good to go..it would get alittle hecktic once you got to the finals,but hell,that was part of the fun for me....as a matter a fact,i'd even wipe the ENTIRE car down between round because i hated when it got dirty,and anyone whos raced with an open wheeled drag car knows what a mother fucker the water box can be...alot of why our car ran so cool,and would'nt keep heat was the alcohol carb,which helps with overheating issues,but creates another issue with the oil in the motor,alcohol creates alot of condensation in the oil do to its radical heating/cooling charactoristics....only bummer part,lots of oil changes!!
Maybe not a fuel dragster but my bracket car uses alcohol and a carb. In order to get it up to temp ( 180-190-) I have a hose running from the PVC port on the carb to the shifter console, It has a 1/4 turn valve and at a fast idle I open the valve up to lean it out . On a 100 degree day the 406 chevy will barely keep warm on it's own. on a 75 degree day it has to be leaned out to get to temp.On a high humidity day it can get frost on the carb main body. Alcohol can draw moisture and dilute the oil somewhat but after a run I lean it out going back to the pits until it's 220 or so. Once we stop the oil caps on the valve covers come off and the oil is hot enough the steam comes out the valve covers. The oil stays good enough I only change it twice a year.
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