The Australian modified ute fraternity seems to be on the up at the moment, with extroverted utility owners oozing out of the woodwork with some amazing creations. Having an opportunity to pedal their outlandish cars on a daily basis inspires them to create ever improving rides, not the least being Kris Bosdorf's highly irregular HZ 'tonner.
Then again, anyone checking out the pics of Kris's car may be tempted into thinking of it as just another 'tonner with a chequerplate rear. Well, it's a lot more than that, and we're not merely referring to what lies under the bonnet. Sure, the 32 valve, quad cam 4.0-litre Lexus V8 engine is a focal point, however what you need to understand is that the car is driven daily with a tray chock full of plumber's hardware. Significantly, the all-up towing weight of the vehicle is typically more than three tonnes thanks to the heavy-duty tow bar and a well decked out trailer.
"Look, I'm no rev head, never have been, but recent events have pushed me in that direction," said Kris as we captured his car on celluloid at a recent Calder street meeting. His first drag meeting actually and his first taste of burning rubber and eight second time slips. "Now that I've got a taste of drag racing, it's aroused my interest in performance."
Back To Work
The tonner has been in the Bosdorf family for seven years, providing reasonable service from the original asthmatic 253/slusher combo. "As soon as I fitted LPG, things started to go downhill. Constant starting problems and cracked heads pushed the point, so I decided to update with a new driveline. Initially I considered a Holden EFI five-litre; however, they were becoming very common. Then when speaking to someone about an engine swap, they suggested I try the Lexus V8, and it went from there."
Performance aside, Kris likes his rides to look the part, and importantly, they must provide reliable service. In fact, the entire aesthetic package seen here was completed years before a single spanner made its way into the engine bay.
Kris performed almost all of the work himself, kicking off with a bunch of hand-carved interior goodies including the armrests, centre console, and dash inserts. The chequerplate theme continues with the kick panels, and a centre console insert, the latter mounted below a trio of VDO Classic gauges. A wood-rimmed SAAS twirler is placed in front of a factory dash equipped with VDO Classic speed and tacho, Pioneer CD and Kenwood speakers. Toyota MR2 buckets, new carpet and hood lining complete the interior.
Mario at Expert Smash repairs fronted the ute with Statesman tin before topping all in a custom gunmetal grey/blue Dulux 2k mix.
Tray mods had already been completed when Kris bought the vehicle - the previous owner producing a large slide-in under-tray while lowering the tray mountings by some 75mm to provide a much classier street appearance. Furthering the cause, Kris booked his ride into Pedders Bulleen where the boys fitted a full set of sports shocks. They also reset the leaf springs while slipping on lowered front springs and a bunch of Nolathane bushes.
The exhaust stacks would come later, and in the meantime Kris lowered the tonner over 15 x 7 and 8-inch Cragar rims wrapped in 205/60 Bridgy and 265/50 BFG TA tyres.
Without going into long deliberations, once the 253 spat another head gasket, Kris decided the time was right to change to a new engine. "I took the car to a recommended workshop and they said they could do the job, no worries. So I left it with them only to be told some months later that they hadn't the expertise to complete the task," said a dejected car owner. Another workshop was tried, however after only two days, Kris received a telephone call advising that they too hadn't the expertise to complete the task.
In desperation, Kris phoned around and found that all indicators were that Maztech of Melbourne was the place to go. Interesting, given that Maztech are well known for their 10, 9 and 8-second rotaries. What the hell, Kris decided to go for it.
"When the tonner came in, the engine, trans and diff had been fitted, however the problems were so significant that we really had to start afresh," explained Maztech head honcho, Anthony Rodriguez. The wide engine was removed and new engine mounts made that would both push the engine forward and higher up in the bay. "As it was, the engine was so low you couldn't even fit a sump."
A new sump was fabricated, the neat Barney's Exhausts extractors were cut and shut to allow for the altered engine position, and the oil filter relocated to a remote position on the passenger side inner guard. A distinct lack of room at the front of the engine meant that Maztech had to bypass the fan oil feed (engine oil is used to turn the engine fan), and front the PWR-prepped radiator with a large 16-inch Davies Craig thermo fan.
Incredibly important in any engine conversion is maintaining appropriate drive line angles, ensuring the crank is positioned in line and at the right angle in relation to the transmission and tailshaft. This was of course taken into account.
With the engine out, Maztech checked the internals, pulling a main cap to reveal it as being in as-new condition. Anthony was absolutely amazed by the quality of the engine, not merely its condition, but how Lexus (Toyota) designed such an incredibly strong combo.
"The most difficult task was adapting an engine management system. It took us quite a lot of time to work out how to negotiate the electronics associated with the twin dizzy setup. With each bank running one dizzy, but with one pick-up, it posed a problem, however we made some changes to the Microtech MT8 computer and it proved an absolute breeze to tune. I have to say that the Lexus engine is a pleasure to tune in that any minute change can be seen immediately and the results are incredibly pleasing."
Maztech finished the engine bay with the remotely mounted Ryco Z9 filter, there's a custom alloy wiper washer bottle, alloy radiator cover, and a bunch of braided line.
The Barney's Exhaust package of extractors, and twin hi-flow cats, leads to two large stacks - typical of what we've seen since the introduction of the V8 Brutes and the Ute Muster racing classes.
A Dellow Automotive adapter sits between the Lexus engine and import Supra five-speed transmission, while playing host to a Maztech 12A Turbo style heavy-duty diaphragm clutch. A custom-made shifter tops the mechanism, the trans rests on a fabricated crossmember, and the front section of the tailshaft is modified to accommodate the Toyota trans.
With a stack more torque than the little Supra trans was designed to cope with, plus the heavy weight, there have already been two blown transmissions, with Kris stating that an Australian Supra Turbo 'box is about due to see its way under the vehicle.
The obligatory Ford nine-inch diff with 3.5 LSD centre rounds out the driveline.
Once a new trans is in place, the only other mod Kris will undertake is a brake upgrade. Yep, turns out that the stock HZ discs and rear drums simply aren't up to slowing the tonner down.
But that's what you get with older model vehicles. The more power you make, the more attention has to be paid to handling and braking. Actually, this applies to any high performance vehicle. And hey, with more than 300 horsepower under the 'tonner's bonnet, it's definitely a high performance sleeper.