Ivan Stewart's Toyota Trophy Truck

ALL THE INSIDE SECRETS YOU AREN'T SUPPOSED TO KNOW

Nov. 01, 1997 By Rick Sieman

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When the factory Toyota Trophy truck appeared on the starting line of the Baja 500 in Ensenada this June, a huge crowd quickly gathered. And when Ivan fired up the impeccably-prepped truck, it sounded like a Pro-stock drag race motor under the hood.

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The snarl of the new V-8 was chilling, and Ivan sat there, grinning like an idiot, loving every second of it. I bulled my way through the crowd, using time-honored techniques: "Watch out! Contagious leper coming through!"

After clicking off a few shots, I caught Ivan's attention and shook hands with him: "So, what's it like with this new motor?"

The grinned widened: "Rick, all these years I coulda had a V8. This thing is great! If it doesn't break, no one will beat me."

No one beat him.

End of story, but the beginning of our story.

With all the wild rumors floating around about the all dominating Toyota Trophy Truck, we thought it might be interest ing to get the real scoop. After contacting Ivan, he set the deal up with Cal Wells, owner of Precision Preparation Incorporated (PPI), and Cal agreed to let us in on all the secrets.

The Iron man tries the seat of a Toyota Indy car to see how it feels. Will he race one in the future? The reply: "Maybe in one of those celebrity events. Heck, it would be fun."

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At PPI, where Ivan's race truck is prepped, we also were surprised to find a garage full of Toyota-powered Indy cars. Talk about a motorhead's paradise!

JUST A ROUTINE PREP

After each race, the motor is yanked out of the Trophy Truck and sent Toyota Racing Development (TRD) for inspection and rebuild.

Then, the entire truck is deep-stripped ... and we mean deep. Every piece is taken off the truck, cleaned, magna-fluxed and then sand blasted to perfection. Previously painted items get a fresh coat, but the roll cage structure and suspension links remain bare metal.

Every bearing is checked and replaced if out of tolerance, or past the maintenance schedule. Shocks are completely rebuilt, the trans comes apart, brakes are rebuilt and the kevlar Toyota replica body parts go to the shop for fresh paint and stickers.

SPECS AND STATS

All up weight of the truck, full of Trick Racing gas, is 3900 pounds, substantially lighter than the other Trophy Trucks on the track. The center-mounted fuel cell carries 43 gallons and needs every drop, since the rowdy Toyota gets an average of three miles per gallon under hard racing conditions. Weight distribution is 60 percent rear and 40 percent front.
Suspension travel is 22 inches all the way
around. The truck designers said they could quite easily have run much more travel (and they have in the past), but felt that 22 was a good compro mise in bump-eating ability and handling. Too much travel, and the truck will wallow in the turns. If you've ever watched Ivan Stewart on hard-packed twisty fire roads, you know that's one of the places he makes up a lot of time.

One Bilstein shock does all the work per wheel. Shaft stroke

With nothing hanging low, the Toyota has ground clearance to match the Unlimited buggies.

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Bilstein shocks have special by-pass valves and finned coolers built into the reservoir lines.

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on the front shocks is
11 inches, while the rear has a longer 14 inch stroke. This gives the truck a rather mild suspension lever ratio of 2:1 up front and about 1.6:1 at the rear.

Each Bilstein shock runs about 1 1/2 quarts of fluid, and has cooling fins built into the lines. By-pass valves are used, along with a typical Bellville washer stack for the initial damping valving. Six inches of sag is dialed into the suspension, keeping the truck very low when being driven on normal flat ground. The idea for this much sag was taken from Toyota's experience with stadium-type racing. The truck simply corners better sitting low.

Still, all is not perfect with the suspension. While supple and able to blast through whoops and ripples without a twitch, Ivan's truck does not take big square G-out hits well. Here, he rolls off the throttle and eases through the big dip. Work is still ongoing to improve this slight bottoming-out problem.

HOW FAST IS THAT SUCKER?

We saw actual dyno readouts of slightly over 550 horsepower at between 7200 and 7800 rpm. At one time, they ran the motor up to 8400 rpm and got a peak reading of 580 horsepower! With no rev

Going, going ... gone. Ivan neared speeds of 140 miles per hour on route to winning the Baja 500. He waved to the ORC.COM crew just north of Santo Tomas at this speed. Click Here for 640x428

limiter in place, the engineers simply
don't know how high the engine will rev, but one man said he thought that 10,000 rpm was possible. For practical purposes, Ivan normally will shift at 7,000 rpm, or earlier, if conditions permit. On long straights, 7800 rpm is the normal max. This translates into 130 plus miles per hour!!! Ivan feels, that if he had to, he could hit 140 on pavement.

The highest recorded speed to date has been at Barstow, where the truck reached 137 mph at slightly over 8,000 rpm. Enough.

New V-8 motor actually is lighter than the old V-6, and puts out almost twice the ponies. Click Here for 640x480
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The engine supposedly starts life as a V-8 T-100, but in actuality, it's from the Lexus family of blocks, which vary a bit from the T-series. At 4.9 liters, the compact V-8 starts pulling hard at 4500 rpm, all the way to red line. It will comfortably grunt a bit at lower revs, but the real fun starts at 4500.

Oddly enough, the V-8 weighs nine pounds less than the V-6 that used to have a home under the hood. Weight of the motor is approximately 340-350 pounds, depending on if it's weighed with or without certain accessories. Just in case you wondered, maximum horsepower on the old V-6 was a mere 300 to 350, depend ing on what kind of course tuning was dialed in.

Big holes: TBI inlets are a whopping 56 millimeters each. Click Here for 640x480
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Eight EFI throttle bodies with whopping huge 56 mm bores
feed the four-valve heads. J & E forged pistons run a moderate 13:1 compression ratio, but still demands the use of higher octane racing fuel. The ignition is computer-controlled, and has a back-up black box that can be replaced if things go south.

So far, the unit has proven incredibly reliable. In fact, after the Baja 500 race, a complete tear down was done and every thing was still in spec. Pistons and rings were replaced as routine maintenance, but everything else was nuts-on perfect.

MO' SPECS

A Hewland VGC-200 model trans is used; it's a five-speeder that's normally found in GTP applications.
A Tilton carbon fiber 2-disc clutch has proven virtually trouble-free. Those discs are a smallish seven inches.
The drive shaft - if you can call it that - is a simple coupler, a double Cardan assembly.
Cooling is accomplished by a Fluidyne aluminum radiator. The truck normally runs at 210 degrees. Shut down temp is 250 de grees, or a call is made by radio for advice.
An Earls trans cooler the size of a library book keeps the gears from spinning in hot gear oil.
Ivan runs BF Goodrich tires; the tire wheel combination weighs 130 pounds with the 37 X 12.50 X 17 rubber mounted.

IS IT AN ALL NEW MACHINE?

Overhead view shows the bare chassis; triangulation for strength is incredible. Click Here for 640x480
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Not even. This is basically the old truck that's been run for the last few years. The V-6 was yanked out and the V-8 slapped in. It took three months to build the V-8 version, and the guys got in done right the first time. Naturally, they had to in crease the rear axle size and the transmission input shaft has been heavily upgraded.

Numerous other items were upgraded, including the fuel delivery system. You want exotic? Check this out: Each individual cylinder can have the timing or the jetting altered.

That 43 gallon fuel cell is not your normal foam-filled bladder with a thin sheet of aluminum wrapped around it. Instead, the cell is made of thick T-6 aluminum and is an actual structural member of the vehicle! Without this cell in place, the chassis would twist like a hot stick of licorice.

Brakes are based on 14 inch rotors hand made from 4130 chromoly steel, and yes, they're made in-house. Brembo 4-puck calipers use semi-metallic pads. Oddly enough, the power brake assist is taken directly from the power steering return line. Wild.

Speaking of the steering, a unique hand-built double ram device completely eliminates any bumps from affecting the steering. Even the reservoir has a piston separator in it to prevent oil foaming. Cost for this little honey? Try about $30,000.

The engine sits right behind the seat, making it a true mid engine racer. Hooked directly to the back of the V-8 is that Hewland trans. The "rear end" is built right into the back section of the trans. Massive gears turn the vacuum-melt 4130 axles via the biggest CV joints this side of a semi.


Sitting on jack stands, the bare Toyota looks tall. In reality, ready to race, Ivan's head is well above the top of the cab. Click Here for 640x480 Here for 1024x768	Super hefty CV-joints allow easy articulation of the axles. That small coin is a dime, to give you a size reference. Click Here for 768x512	One-off steering box has double rams and is all hand-machined from billet. Cost? Over $30,000. Click Here for 768x512


Brakes consist of hand-made 4130 rotors with Brembo stoppers. Click Here for 768x512	Talk about trick: a piston separator keeps the power steering fluid from foaming in the reservoir. Cost is about $10,000 for this little item. Click Here for 320x480	Unique fuel cell is an actual structural part of the chassis. Click Here for 768x512

THE PEOPLE BEHIND THE MAN

Since Ivan lived through the early development stages of the four-banger off-road racing trucks, then the V-6, he experienced the woes of development. He still recalls the many races he led, when the Doug-Nash tranny let him down.

So, he tends to drive the new truck on the easy side. Ivan wants to be there at the finish, and knows that if you break your equipment, it might not be there at the finish line.

Once a special part is designed in the CAD program of the computer, the data can then be fed to an automatic CNC machine for fabrication. Click Here for 400x267

Tom Morris, one of the main men behind the Trophy Truck, once cornered Ivan and yelled at him: "Beat it up! You can't hurt this truck!"

He means it, too. As you spend time crawling around inside the truck, you can see that everything is built to take it. The front A-arms are mammoth and pivot on heim joints that ride on hefty Grade 8 bolts. Tabs are thick and gusseted heavily and every stressed point is reinforced via triangulated tubing.

Those men who prep and maintain Ivan's Trophy Truck also work at the races, and they know their job well. Take this example: During one race, Ivan pulled into the pits and the crew changed two tires, dumped 40 gallons of gas, added two quarts of oil, gave Ivan a drink and handed him a clean set of goggles. Total elapsed time? Fourteen seconds!

Tom Morris is proud of the truck: "It's super reliable and we haven't had a real problem for a long time. We don't even let Ivan carry any tools. In fact, the only tool he has to use is the radio, unless he has to change a tire in a spot where we can't get to him."

Even though Toyota has cut back on its off-road racing efforts, they pull out all the stops on the important races, like the Baja 500 and 1000.

Any bets on who the favorite will be in this, or any other Baja 1000?