i noticed and therefore ***ume(perhaps wrongly) that the dragsters and funnies did not seem to use air filters under the injector hat. The current fuel cars probably don't either. Discuss the logic of this practice.
They rebuild the engine between rounds... Air filters help engines last a long time. Race engines just need to last for the race.
Air flow restricton? And I doubt anyone really expects a long life out of a motor that is ran at it's red line 90% of the time it's running ,
OK, but wouldn't running a filter still be a good practice since those blocks ain't cheap............nevermind they run sleves. Cancel the series. i'm real slow---forgive me.
Air filter element restrictive on flow, the oil/fluids on the pro 1/4 mile cars are changed and the motors are rebuilt so often that any dirt pulled through the intake doesn't have a chance to wear on the internal components.
Well my thinking would be the damage done by a a bit of dust, dirt or any other bit of foreign material ****ed into the injector hat on a run far out weighs the amount of damage a pluged filter would do, if the filter would become pluged that could cause a lean condition in the tune up , and running a fuel motor too lean normally leads to burnt holes in pistons,heads and exploisons, these motors are run on the edge of no return as it is, small things turn into big things very quickly, Just my thoughts, Any nitro tuners want to weigh in on this? BTW some use a screen under the hat to catch the big pieces before they can go through the blower
On a blown top fuel car? Probably for the same reason they don't have them on F-16s, it would get ingested when you hit the throttle. LOL. Race cars ingest all kinds of ****, but they are expendable / rebuildable like already mentioned. And air cleaners also do another nice thing, they keep any backfires from toasting eyebrows, or hood or starting a bigger fire if you also have some sort of fuel leak. Gary
The fuel engines turn less that 1000 revolutions between rebuilds. Filtering the air is not going to make any difference it will only restrict air flow.
Not slow at all good legitimate question. You seldom see a filter of any type on an injector hat or even on stack injectors. I does have to do mor with air flow than any other reason. As for the cost of a block even pre-aluminum with sleeves it was common practice to run without air cleaners. It is just considered the cost of winning.
air filter are used on sand drags/truck pulling/dirt circle tracks ect major after market air filter makers have got it covered.........
Some of those guys been runnin fuel cars for 50 plus years if there was any advantage they'd be using air cleaners. Even our sprint car motors dindn't **** the amount of air that a fueler needs I'm guessing anything that would flow enough air would have to be huge by enormous.
BTW, if anyone wants to run a filter under a hat, on the street or wherever, this might work: http://www.project33.com/article.cfm?ID=348 http://www.project33.com/article.cfm?ID=349 2) How did GMC handle the filter issue?
Last time I saw the "Winged Outlaw Sprint Cars" run on dirt, most had an air filter of sorts on top of the injector stacks with all 8 stacks into one big filter. Dave
"Back in the day" I used to at stuff large put rubber balls in the injector stacks between rounds. Forget they were there, push started the engine, and blew rubber bands out the exhaust.......
I run air filter on the road all the time . When I do drag race a car , I NEVER use any filters at all ! The Pros don't use filters because they need the Best Air Flow possibly and race tracks are usually very clean plus they do rebuild the engine after every round . For the very light dist or dirt that might get into the intake , it will be cleaned out when they rebuild the engine anyway . Also those engine are only run for a few minutes anyway so no worry there . Retro Jim
Besides the fact that these engines are rebuilt often enough that they don't care about a little dirt, think about this: the flow of air that a top fuel engine ingests at full throttle would pretty much **** any regular filter right into the engine. If you used a filter that was low restriction enough not to get ****ed into the engine, it wouldn't provide any real protection anyway. An oil bath metal mesh might be strong enough but the oil would be ****ed off and screw up the mixture.
He is ***uming 10,000 RPM for 4 seconds plus a 2 second burnout gets you 10,000RPM for six seconds each run. 10,000 divided by 60 times 6 equals 1000. Engine is rebuilt after each run.
My buddy runs 6.8 in the quarter with his car which has a 14-71 on it and he never seems to have a problem from dust or dirt particles. Problems usually come in the form of broken engine internals (rods, pistons, etc.) He is usually turning between 8.5 and 9K by the end of 1320.
Is the math too confusing, or do you not agree with the estimated times and RPM at said times? 10000 revolutions per minute / 60 seconds per minute = 166.66 revolutions per second 166.66 revolutions per second * 6 seconds = 1000 revolutions Even including the time spent idling at the line, a top fuel engine doesn't experience many revolutions between tear-downs.
Air filters are somwhat restrictive and are only necessary if there is dirt in the air, most dragstrips are not dusty. Boat engines from the factory run spark arrestors, no air cleaners, very little dust on the waterways.
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