The first introduction of the Tsukuba was successful in 1990, and not at peace with the idea of “leaving it as is” the company first turned their attention to the powerplant and gearbox supplied by Saminda. Within a year a power upgrade was developed and implemented into a “Tsukuba S”, with S standing for “sport”. At the same time a convertible option was added along with a minor restyle of the tail lights, engine cover and front end, finished off by a small wing on the back to improve the aerodynamics.
The S version boasted new camshafts, ignition and fuel map, along with a new exhaust, to return 201hp. A new limited slip differential unit was designed to be retrofit into the saminda diff, which also improved handling and acceleration figures. This helped the car to reach 100kph in 5.9 seconds, with the top speed of 242kph. Both figures improvement on the 6.9 seconds and 211kph.
As the popularity of the car rised, KHT has started noticing a lot of the cars being transformed into racing versions and used by teams on a budget and enthusiasts on track days, so a new, extreme version was planned. That combined with the rumors that Lotus is planning a very similar trackday special to be released soon has led to the creation of the Tsukuba R. The team has removed the option of a targa roof or a convertible for the R version (for “Racing”, obviously) to improve the rigidity of the chassis, a wider fenders were introduced to the R version only, to host the wider wheels. Re-worked the front and rear aero to optimize the cooling and went on to save weight on anything they could find. The new wheels were magnesium units, a lot of carbon fiber panels were introduced on the inside, along with a new carbon fiber engine cover and a GT type wing, which sadly was not legal in many countries and had to be designed to come off for street use.
The engine was given a complete work-over, now producing 237hp, still in naturally aspirated trim, as KHT did not wish to resort to turbocharging and remove the clear engine response to the accelerator pedal. Mated to the same gearbox and diff as the S version the clutch was an upgraded heavy duty unit, now allowing the car a 0-100 time of 5.5 sec and top speed of 256 kph. The Nurburgring lap time dropped to 8:24
Tsukuba S Convertible is absolutely wonderful. Even though I usually don’t like mid-engined cars much. I think I should start my “Automation dream car” list
With the growing production of the Tsukuba, and a new materials laboratory working overtime, advancements were made by 1994 in lightweight parts production. First seen implemented on the Tsukuba R. The next step was needed, in which KHT would follow through with it’s second experiment in lightness. By 1996 the world saw the first fully carbon fiber concept car by Kraft haus, the Monte Carlo. Sporting a tiny MR chassis, roughly based on the tsukuba geometry, it was covered in full carbon fiber body, with basic interior devoid of any luxuries. T
The Monte Carlo was a fully working concept, and was powered by a 2.5 liter 2 valve Alfa Romeo Busso V6 , sporting a custom KHT tuneup, reaching 247hp. Which allowed the 710 kilogram car to reach 100 kph in 4 seconds flat, and top out at 280 kph. A light aero was implemented to compliment the slick racing tires, which allowed the early concept to reach 1.25g while cornering. The reception of the car was good, and encouraged the KHT marketing department to start working on a less expensive version of the car that could be sold to the masses
As KHT has picked up the pace after producing a concept of Monte Carlo things turned to worse, as the deal with Alfa never went through, and the only company with a v6 small enough available was Mazda, who turned down the proposition of outsourcing their engines. The search for engines continued for the next 2 years but to no avail, and while that project was on hold, the team of KHT engineers found a new side project. In 1997 Using the left over Atlantic parts new molds were created and implementing the new found knowledge of lightweight materials the chassis was given a new life in the form of Pacific.
Unlike the Atlantic the car used carbon fiber monocoque and body of the same materials, which naturally increased costs, but resulted in immense weight savings. By 1999 the first prototype was created, powered by the same IMP v12 unit found in the 1990 Atlantic. This however had drastic effect on weight distribution, and after a few test tries with multiple engines, a modified BMW M62 V8 engine displacing in 4.4 liters was chosen as a good basis for power and weight. At first an idea of a deal between the two companies was considered, but after close consideration it was decided to build a custom engine in house.
The all new 5 liter v8 engine blocks made of AISI steel, featured the head of the same material, housing 2 cams and 4 valves per cylinder. Deals with Mahle and Eagle were made to provide for internals, which were forged. The complicated to develop VVT and VVL were never considered, and the whole engine was built with race grade standards, producing 611hp at 7500 rpm and redlining 300 rpm later, without the use of a turbocharger. A very sophisticated individual throttle body intake and race grade tubular exhausts were chosen as the best options, without a single muffler or resonator in the whole system.
The car was powering the rear wheels through a 6 speed sequential gearbox provided by summit racing, and was able to reach 100 kph in 3.4 seconds and top out at 364kph, while the handling ability spiked at 1.2g while cornering. The interior was basically a full blown racecar spec, providing competition to the McLaren F1 and a Willis Jeep, while retaining some resemblance of a basic in car entertainment. The updated design of the car did not, however hide the fact that under the new engine and new materials this was a late 80’s design, and it did not please many customers, who did not wish to spend $140,000 for the supercar that was basically new when they still had it as a poster on their bedroom wall. The sales were weak, and eventually the Pacific hasn’t even gotten back the money it owed the factory for the engine alone.
That is a v8 with 0 quality sliders, actually. Material cost of 2000 and 96 production units, weighing in at 175 kilos and a reliability rating of 47.
KHT did sell the engines both as complete package and as a base for modifications to other manufacturers, you can PM me if you want the engine to slot into another car.
There are no secrets, just a good balance of revs and displacement. I’m running 92.5 bore and stroke, everything else is just trying to squeeze all of the power out of it you can. I did sacrifice a few HP up top to have a slightly higher torque at all the revs up to 7k by using a more restrictive exhaust.
Powerful indeed, but without any form of variable valve timing and an extremely aggressive cam profile, the fuel consumption must be horrendous! At least the car it powers is one of your best-looking designs ever… I wonder what you will unleash upon us next!
Also, will you abandon the Monte Carlo, or re-engine it instead?
Your tuning package for the Knight is a worthwhile improvement indeed on the donor car! I am also considering buying up the rights to the Monte Carlo just so that I can give it the engine it deserves.
Edit: is the Monte Carlo’s engine mounted transversely or longitudinally? In the former case I’d only be able to mount a small V6 if I wanted plenty of power.
I’d offer the 3L AluStar V6, but… The Monte Carlo Concept is fairly small, and mid engine, I don’t think the 3L would fit. I know it’s an I4, but would the Knight’s engine fit? Or does it have to be a V6, because there may be some engine surplus left over in some of our older stock. Might be a few 3.4 liter V8’s left over from the Xenon.
(Although, any way you look at it, the closest I’d be able to offer anything up is in a little over a week.)
