HEMI Technical Info

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Chassis: 300-inch, Dave Uyehara built Top Fuel chassis
 Wing: Former three-element Top Fuel wing with one element removed
 Rearend: Strange unit with 10.5-inch ring gear, 2.91 gears, and carbon fiber brakes
 Body: Magnesium with Chrome-moly or Titanium shield

Fuel tank: 17-gallon capacity with 1.5-inch-diameter lines. ( 8-9 gallons per run)
 
Engine: 421ci Billet Hemi .500" short
Heads - a/fuel style of Fat Heads

JE (and if you want a set of exact reproductions just use Job # 668377 for a reference). They have a compression height of 1.555 inches, a pin diameter of 1.156, a pin length of 2.93 inches and a dome of 0.440 inches and they utilize three rings. / 805 grams a piece. -compression ratio of 13.5:1

Billet aluminum rods that measure 6.951

Crane (RIP) part number 66R000802. It is ground from a special 9310 steel core and is designed to be used with 0.902-inch-diameter roller lifters. Intake lobe lift is 0.540 and exhaust is 0.5003. Combine that with the 1.57:1 ratio intake rockers and 1.52:1 exhausts, and you’ve got total lift of 0.848 and 0.760 respectively. The advertised duration is 307/316. The duration at 0.050-inch tappet rise is 278/284- installed at 25 degrees at 0.050.

Clutch: Crower six-stand, 12-lever, 10.5-inch clutch with four discs and three floaters

Fuel system: Waterman 58-gallon pump
Take 58 GPM the pump is rated for and divide it by 8,000. Now multiply it by the new initial hit rpm of 5,000. That equals 36.25 GPM. At this point the crew cheif neeeds to pull 9 GPM to get down to the 27 GPM he wants. If the engine only went to 4,800 rpm and smoked the tires, they could take 20 grams of weight off the clutch (tp change how hard and soon the car “hits” the tire, or reduce of 7 GPM (58/8000 X 4800 =34.8 — 27 = 7.8 GPM). If it smoked the tires, he’d take maybe 5 degrees of timing out and try it again.
Tires: Goodyear 34×17 slicks on the business end run at 6-6.5 psi
Weight: 5 pounds per cubic inch,  minimum weight 2,150 pounds. This one comes in around 2,200.
Computer: Race Pak Pro 1A. Data comes from eight EGT sensors, a driveshaft sensor, an oil pressure monitor, a g-meter, two engine tachs (due to the dual mags), a fuel pump pressure gauge, a fuel nozzle pressure gauge, and two fuel flow meters that monitor the fuel that goes through the barrel valve into the motor and the fuel and bypasses it on the return side back to the tank.
 Performance: A typical 60-foot number is an eyeball-flattening 0.930 seconds, and the car will 1/8 mile at 3.5 second at 220 mph. The quarter mile comes up at around 5.3 seconds .
The fuel pressure when the car is idling is about 10 psi at the barrel valve and distribution block. At this point, the nozzles in the heads have nothing going through them as they have springs and check balls in them that do not allow any flow until 38 psi. Once the driver puts the fuel pump on the “high side” and full flow is happening, the pressure rockets up to 120 psi at 2,700 rpm, a ballpark normal idle speed.