Um No 
but it was good wasnât it ?
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One of my fave racing videos!!!
Kyle ,actually Jaguar did make some V12s 4.9L, they made little over 500HP, but at 8000 revs.
who drives around at 7500/8000 RPM?
imagine trying to pass someone without much torque, spend to much time shiftin gears , if you have enough of them.
altho these new 10 speed gear boxes might get it done, course automatic trans!
to add, Allen Scott, head engineer for TWR racing, said that for a street driven Jaguar V12 , cheapest way would be to stroke it as much as funds would allow, all the other mods reduce torque in the low/mid range were it is needed to pass or pull onto fast hiway ramp.
again he did nt know much about cars!
and HE engines were designed for better MPG and emission regulation, they were never intended for performance use!
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WIGS ,i bought many race parts from Mickey Thompson, back in early 60s, and when he saw i was not wasting his time , he sent some unbeliveble pistons and con rods!
shame what happened to him, but like some super intelligent guys ,he pissed a few off!
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Eat yer hearts out, we are going to be attending the 13th National Jaguar rally in Invercargill over Easter and Allen Scott is one of the guest speakers along with a video message from Norm Dewis (Auckland JDC patron)
Looking forward to the drive as much as the event.
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Yeah, the 4.9 thing is exactly what I was thinking! I have no intention of ever doing it but the site I was looking at does something similar and uses the engine is the middle of an open wheel racer. Very Antique formula one looking.
The idea they got more horsepower at super high revs is what I was trying to wrap my head around. But what your telling me as well as a bunch of time with the post on power in joules I think gets me a basic understanding of whatâs happening.
The thing thatâs left is does decreasing the cylinder size make the existing valves adequate as they are proportionally bigger? Were the heads on the 4.9 the same as the heads on the 5.3 or were there changes there as well
Darkworld cascadr, the 4.9L Jag V12 is no relation to the V12 5.3L or 6.0L,none whatso ever!
it was a 4 cam , Hemi head, almost no torque below 4500 revs.
.
that is why Jaguar/ FORD went to 6.0L all done with stroke, they lengthen it 7.8MM, longer, nice .
also there is a big difference between a street vehicle and a race car!
like a modern F1 engine makes 850+ HP, but only has 250 lbs ft torque!
now the king of power engines , nothing in the known world can match an old USA hot rod , top fuel engine!
they cant measure them because MATH says power is over 10000,HP. torque DAMIFINO.
and they can actually fit in a normal car, latest records show 338 MPH, in 3.6 seconds.
in 660 ft they are doing over 250 MPH.
ron
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and using jag 5.3L valve shrouding is already considered not good, some guys bore cylinders larger to make more room for air flow where valve is close to the bore!
kinda look at trying to fill the cylinder more, not fill the head or chamber
ron
in this modern world , forced induction is by far the best way to get air in the cylinder.
quick thought ; if you can make just 15 psi in the inlet manifold, theory says 100% increase in power(or close).
so 30 psi says 200% , all the silly old ways of porting and port shapes, valve sizes, volumetric ef.
if there is some minor changes in port shapes , positive pressure dont care it just forces the air in at higher velocities .
ron
one of the best engine available , is the rotary, some have been measured at over 300% volumetric effenciy.
ron
And, the physics involved is MIND-bending!!
âEver wonder why a Top Fuel dragster gets a rebuilt engine after each run?
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One Top Fuel dragster outfitted with a 500 cubic-inch replica Dodge (actually Keith Black, etc) Hemi engine makes more horsepower (8,000 HP) than the first 4 rows of cars at NASCARâs Daytona 500.
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Under full throttle, a dragster engine will consume 11.2 gallons of nitro methane per second; a fully loaded Boeing 747 consumes jet fuel at the same rate but with 25% less energy being produced.
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A stock Dodge Hemi V8 engine cannot produce enough power to drive the dragsterâs supercharger.
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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 lockup at full throttle.
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At the stoichiometric 1.7:1 air/fuel mixture for nitro methane the flame front temperature measures 7050 degrees F.
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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.
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Dual magnetos supply 44 amps to each spark plug. Which is typically the output of a small electric arc welder in each cylinder.
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Spark plug electrodes are totally consumed during a pass. After 1/2 way thru the run, the engine is âdieselingâ from compression and the glow of the exhaust valves at 1400 degrees F. The engine can only be shut down by cutting the fuel flow.
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If spark momentarily fails early in the run, unburned nitro builds up in the affected cylinders and then explodes with enough force to blow the cylinder heads off the block in pieces or split the block in half !!
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Dragsters reach over 300 MPH +⌠before you have completed reading this sentence.
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In order to exceed 300 MPH in 4.5 seconds, a dragster must accelerate an average of over 4 Gâs. In order to reach 200 MPH well before reaching half-track, at launch the acceleration approaches 8 Gâs.
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Top Fuel engines turn approximately 540 revolutions from light to light!
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Including the burnout, the engine must only survive 900 revolutions under load.
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The redline is actually quite high at 9500 RPM.
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THE BOTTOM LINE: Assuming all the equipment is paid for, the pit crew is working for free. & NOTHING BLOWS UP, each run will cost an estimated $1,000 per second.
0 to 100 MPH in .8 seconds (the first 60 feet of the run)
0 to 200 MPH in 2.2 seconds (the first 350 feet of the run)
6 g-forces at the starting line (nothing accelerates faster on land)
6 negative g-forces upon deployment of twin 'chutes at 300
An NHRA Top Fuel Dragster accelerates quicker than any other land vehicle on earth⌠quicker than a jet fighter plane⌠quicker than the space shuttle⌠or snapping your fingers!!
Letâs now put this all into perspective:
Imagine thisâŚYou are driving a new $140,000 Lingenfelter twin-turbo powered Corvette Z-06. Over a mile up the road, a Top Fuel dragster is staged & ready to âlaunchâ down a quarter-mile s trip as you pass. You have the advantage of a flying start. You run the 'Vette hard, on up through the gears and blast across the starting line & pass the dragster at an honest 200 MPH⌠The âtreeâ goes green for both of you at that exact moment. The dragster departs & starts after you. You keep your foot buried hard to the floor, and suddenly you hear an incredibly brutally screaming whine that seares and pummels your eardrums & within a mere 3 seconds the dragster effortlessly catches & 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 MPHâŚand it not only caught, but nearly blasted you off the planet when he passed you within a mere 1320 foot long race!
Well, that thing about the 747 is WAAAAY off. I dunno how fast it consumes fuel, but each engine produces an order of magnitude more power than the dragster.
The number I found was that a 747 uses about 30t/hr in climb, then 12t/hr at cruising altitude.
That makes for 500kg a minute, 8kg every second. Takeoff might be slightly higher, I donât know. 8 kg would be 2.2gal imp.
The given example is that the dragster ingests 11gal/sec of nitromethane, at a mixture of 1.7:1 whereas the plane needs a mixture of 16:1.
I donât want to go into energy density or air, but at least it is probably fair to say that the dragster does consume considerably more fuel volume than the plane ever could.
But the plane has significantly more âhorsepowerâ⌠um.
Looking up Pauls text on the interwebs I see another figure of 1 ½ gallons per second. That is what, about five litres? Thatâd make more sense, especially power wise. Also, if the engine makes a total of 900 revolutions in about 5 load seconds then how can you run 50+ gallons of liquid through that engine?
So, no, 11.2 gallons: definitely no way.
David
No particular defense of the numbers, but they seem to have come from Schumacher Racing: Ill tend towards belief.
https://www.google.com/amp/www.motortrend.com/news/top-fuel-numbers/amp/
Now 900 revolutions in 5 seconds are 180rps. 90 cycles per second have to pump 1.5 gallons of nitrous and a bit of air.
1.5gal=5.7 litres divided by 90 is 63cc fuel per combustion, and being 1.7:1 another 37cc of air: total of 100cc in the chamber.
Now it gets foggy but doesnât that have to be compressed by a lot? We have some air numbers (by the way, a 747 moves 4.5 tons of air per second!) and so on. Yes, dragsters are interesting contraptions.
//63cc of fuel and 37cc of air at 3bar. Probably way off but still reasonable
A video of ONE cylinders fuel deliveryâŚ!!!
http://terrymcmillen.com/2009/12/how_much_fuel_does_a_top_fuel/
Thatâs a lot. Also looks like 1.5gal/sec, not 11.5- and in fact more than half of a 747! How do they even tune their carburetors?
Yup:
77
Gallons per minute the fuel system can pump at wide-open throttle. The engine will consume 22.75 gallons of fuel during warmup, burnout, staging, and the quarter-mile run.
77gal/min is 1 ½ gal/sec! 
And nitromethane AINT cheap!!!
Nitromethane contains its own oxidizer, does it not? So the combustion is only partially reliant on the air being pumped in by the blower?
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