Updates for 2007
originally posted 1-10-2006
After completing the 9th Stage the Hummer was driven directly to Dakar for shipment home. Once back at the team’s headquarters in Anaheim, Calif., Gordon’s off-road crew will completely disassemble the H3 and begin preparations for the Baja 500 in June.
The Hummer was taken out of the race by circumstances that are truly encouraging. I say encouraging because, no suspension failure, not a horrific crash with parts all over the desert, not driver injury, not a massive engine explosion any of what you may expect would take the Hummer out. The Hummer could still have won stages.
The beginning of the end was a bolt. Then a slight impact at the Achilles heel, the radiator. However, these slight mechanical failures are not what sent Team Dakar USA home at the end of stage 7. A series of circumstances is what ended the race after stage 7. One circumstance being the in race T-4 support also faced issues in the sand at a critical time, leaving the H-3 and crew marooned. In the end logistics what it takes to beat Africa. Africa will beat everyone down, every time at some point. Every car up till this point in the race has faced set backs by the halfway point. Set backs such as being stuck in the sand, wheel hubs failing, roll overs, engine management glitches, multiple tire failures, getting lost and more.
Robby never got stuck, Never had a flat, never ran out of gas. He just never had the support it takes to address small issues in the middle of nowhere in a timely fashion.
What's the fix for next year? Logistics, this can not be under estimated, mainly in the area of on track support. Maybe, another H-3 entered in the race as a T-2, several T-4 trucks, a convoy of H-1s entered in the 4x4 Open class, a convoy of H-3s entered in the T-1 class. All of the above? A phone call to Hummer compatriots Rod and Chad Hall?
Ok, so Fly (The eternal optimist) pumped the bad ass H-3 up quite a bit prior to the race. I swear it was going to be a Lay down. It was so close, it was right on the cusp of being the class of the field. The car may not have been as good as the driver too. I can say this, it ran up front. With 5 top fifteens in 7 stages the H-3 really showed this combination could prove to be the right choice. Off road cars are like fine wine, the older they get the better they get.
Hypothetically speaking, what are some of the things I would do with Robby's H-3? (Provided I had the bucks and The Monster)
My virtual Crew Chief technical changes for next year;
Two set ups. (2wd is the only class that allows for different tires at different times)
Flat tighter stages;
*Lower car 7”
*Shorter, single, 3” piggy back coil-over shock package
*Sway bars,
*35x13.50R17 Toyo Tire (60 lbs less)
*14”x1.375 rotors
*6 piston caliper
Longer Rougher Stages;
*2.5”coil-over x 3” By-pass
*No sway bars
*37x14.50R15 Toyo Tires
*12”x 1.25 Rotors
*4 piston caliper
Addition handeling enhancements;
*2 fuel tanks. One 20+Gallon located up front to be used on shorter fast stages to balance car better. 1 60 gallon beneath and behind seat tub.
Drivetrain
*New push rod engine using the 37.2mm restrictor, would need to be a 7500-7800 RPM small bore (3.90) x long stroke (4.30) (6734 CC's or 411 C.I.), 6.30 Rod length this will increase piston speed, intake velocity and static compression. Run a small valve (by NASCAR standards) Canted SB 2.2 head with 2.10 intakes and 1.7 exhausts. Solid roller cam shaft (.375 lift at the tappet) with a 1.8 Jessel shaft rocker total lift (.675). The intake would be multi-port cross runner with a throttle for each runner with a large flow shaped plenum with a ninth injector in the plenum. Optimize the 37.2 restricted intake charges by splitting the one restrictor into the allowed two restrictors of the same area. In a shared volume plenum each restrictor would feed from cylinder 1-4 and the second would feed cylinders 5-8 respectively. I would also run a 4/8/9 injector use setting for fuel mileage.
This combination would put the target wieght at 3417 lbs or 1550 KG.
New Solid CAD model of manifold, FIA restrictor and filter system. (Restrictors in red) Plenum not shown, because it is double secret.
However, if I could change one thing in the engine category; This is what I would do with the unregulated crankshaft rules;
I would run a 4.30 stroke split journal even-fire crankshaft. V-8s have a shared journal/pin. Having a common pin crankshaft two pistons fire every 90 degrees, two cylinders produce maximum demand at the same time. Having a split pin configuration, cylinders fire every 45 degrees, thus only one cylinder is at full vacume at a time. An even-fire crank shaft produces smoother power, higher RPM and increases air-velocity through the restrictors. Outlawed by NASCAR but, Jack Flannery ran these in CORR and they work!
The pics show a forged racing V-6 version and a CAD solid model I did of a 4.30 stroke V-8.
Other Drive Train changes;
*Six Speed Transmission.
*3 disc clutch
*A tick lower final gearing.
Get car closer to 3400 LBS, with a target weight of 3417.
Disassembling the claimed 4500lb car, should be a very methodical process. Since this Hummer is a one off prototype many of the components are purpose built items that have yet to be analyzed other than fit and function. When the car is disassembled EVERY part should be added to a parts list (bill of materials) with a description, quantity, weight and an engineering drawing. Then each item on the list can be evaluated individually. During evaluation items are considered to be made from lighter materials, or a lighter design. When the car is down to the bare chassis it is also weighed and evaluated. Ounces eventually become pounds. Redoing components now doesn’t say they were wrong in the first place; it’s just about optimizing what is there. In the end, a race car that is documented is a race car with spare parts that can be duplicated by multiple sources/vendors.
Having a lighter car helps accomplish many goals of a race car; Increased power to weight, Car becomes more responsive to driver input in the turns and under braking, Better fuel mileage, floats on the dunes better and most importantly is a higher reliability factor. When an Off-road car is light in the desert the car and passengers alike take less of a beating. This is because the overall G-forces incurred on the chassis and drivetrain are reduced too.
As the Hummer stands calculations equate to; removing 1000 pounds would be the same as adding 155 horsepower
Quick reference of a lighter approach (obvious path);
*Move Radiator to the rear above engine. (Saves water weight too)
*Analyze all tube structure and replace all tubing with smaller diameter or thinner wall tube where applicable.
*Carbon Fiber Co2 tank.
*Carbon Fiber Dry Sump tank.
*Remove air conditioning system.
*Incorporate Hydro jacks directly into rear hoop. (convert to air over Hydro)
*Scoot rear spare tire and mount into rear cage structure. (Spares to have spun aluminum wheels)
*Replace all aluminum with Carbon except pan and skid protections.
*All fasteners Titanium.
*Make carbon/aluminum sand ramps located below front body work
*Titanium pedals.
*Titanium steering shaft.
*Change spare rear tire mount to lightened hub snout with spare hub and bearing assembly mounted, then mount spare to hub studs.
* Change secondary spare mount to machined flat studded flange attached to engine cage and no tubing around it.
*Large aluminum front bumper that looks more like H-3 bumper. (Doesn't save wieght but looks cool)
*Precise aerodynamics of external air scoops feeding to a carbon fiber large surface flat filtered funneled ram air box and radiator.
Full interior
*One piece carbon seat tub full width and to top of doors. Between seats integrated compartments for assorted hardware, Tools, required ASO/Score passenger kit. Storage for 4 gallons fresh water, 2 gallons of oil.
*One piece carbon floor and center console full width up to door.
*One piece dash with Motec engine management screen and single 15” LCD touch screen integrated.
*Redesign a lighter shifting system
*Single dry cell battery located above transmission close to starter. 7 lb 14VDC NiCad additional located between seats.
*This next one will save well over 50 Lbs and make the car more user friendly (USA STYLE)* Change all electrical switches and gauges to Class 3 solid state circuits with One large color LCD cockpit display/touch screen for co-driver including Nav, GPS, odometer, sat phone, engine management processors built in as one P4 processor unit. All interior and Marker light converted to LED. LED lighting over engine bay, 4 in cockpit at each wheel. All wiring can be switched out to 22ga NANO cable. 4 on board cameras integrated into system with digital recorder.
I'll be back the next time Robby hits the Dirt in the H-3
posted by FLYHIFLYLO @ 11:55 AM
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