Honda :
More than 20 years ago, we entered in the Olympus Rally, which back then was a WRC event, with our Cultus. I was in charge of the electrics. Everything was so new to us. There are two things in particular that I think back on from that experience. One is the way our suspension collapsed in midst of the rally. I didn’t put much thought on it then, but looking back, I think our machine basically lacked the strength necessary to endure the run. We still had a lot of way to go, a lot of thinking to do, in terms of the basic quality of the car.
Secondly, I had a strong impression that the European machines in that rally were entirely different kind of cars. They all seemed to be so refined in every way. Their performance clearly reflected a great amount of effort put in by a wide range of experts; they were thoroughly toughened up in their long years of racing. The exhaust note of those machines seemed to breathe the builders’ enthusiasm; it almost made them seem alive. They were all on an entirely different level. The shock I felt back then has become a major driving force for me. It is my strong desire to take our WRC participation with the SX4 in such direction.

Honda :
In designing the SX4, we decided, from the start, to put more emphasis on the basics. Considering a car is basically a tool for driving around, first and foremost you need a surefooted chassis/suspension and a body that can steadfastly absorb the suspension action. The suspension was also designed with large tyres and a generous amount of wheelstroke for full customer satisfaction when taking trips to the countryside. Body rigidity was drastically heightened, particularly at the suspension mounting sections.
I believe it’s a design concept that will also bring a big advantage when it comes to rally competition. It’s actually the same, whether it’s a production car built for the customers’ daily use, or a competition machine built to deliver the limits of performance: by pursuing the basics and insisting on good basic “character” and “potential” for the production car, such qualities also come alive in racing programmes - the goals for the production car and the competition machine intertwine quite neatly. For example, we’ve been hearing that the idea that it’s okay for competition vehicles to require highly complex and difficult driving operation is wrong; that actually, to win you need a car that’s, in many ways, “easy to drive”. This was quite an eye-opener for us. We will continue to work with SUZUKI SPORT in our goal of making the SX4 a car that can respond to driver inputs in a “straightforward manner” and is in many ways “easy-to-drive”, so that it’s not only driver-friendly, but also allows rally pilots to more fully express their competitive driving skills.

Honda :
In developing the SX4, we made a wide departure from SUZUKI’s earlier thinking on body design, with the understanding that no matter how much effort we put into the suspension, a high overall handling performance will be out of our reach if it isn’t accompanied by a sturdy body. We realised the body rigidity should be raised not by 3 percent or 5 percent, but by tens of percentage points

Minoru Sasaki :
We focused on two things in designing the SX4 body. One is to provide a sturdy framework to heighten the vehicle’s overall rigidity. As a result, the overall bending rigidity and torsional rigidity are increased by more than 50 percent compared to our earlier design standards. Also, the SX4’s tyres are sized quite large, so it also has a lot of wheelstroke. The body had to be built strong enough to match the suspension action. We particularly focused on heightening the rigidity at the front and rear suspension mounting sections.

Honda :
We would receive from our testing department target figures for sideways rigidity, and we wouldn’t finalise our design drawings until the simulations indicated we’ve reached the figures. That way, we made certain the production car will have strong “basics”. Even when the scheduled date came for submitting the design drawings, if we thought there was more we could do, we would spend an extra three or four weeks to make sure the body design fully reached the figures we were aiming for. Furthermore, when we noticed certain qualities of some of our European rival cars – such as their handling performance, the way they respond quite precisely to the drivers’ inputs while maintaining much stability - we not only test-drove them ourselves, but also measured and numerated their body strength

Minoru Sasaki :
“We believe the SX4 has body-strength figures that match those of our European rivals.”

Honda :
The high body rigidity will surely be a big advantage. Rally competition involves hard driving over a wide variety of course surfaces, so the suspension is a huge deciding factor, but no amount of suspension tuning will provide high total handling performance if it’s not accompanied by a sturdy body, if the rest of the chassis doesn’t hold steady. Starting from a sturdy basic body, we put in reinforcing pipes in a certain manner to obtain specification “A”, which should deliver a certain handling performance “A”; likewise, a specification “B” would deliver a handling performance “B”. That way, the body design should reliably correlate with the handling performance. If a specification “A” body we chose for obtaining handling performance “A” actually ends up delivering handling performance “B”, we would not have a good rally vehicle. This way, a production car with high body rigidity is a precondition for rally success.

Honda :
I believe the J20 engine powering the SX4 has fine potential as a base for a competition engine in many ways, such as the way it’s designed with emphasis on light weight.

Takamitsu Sasaki :
You’re right; the J-20A has been in production now for 10 years; through the decade it’s been yearly improved and its reliability has been heightened to very high standards. In modifying the production engine for rally use, we of course need to strength the rigidity of the crankshaft areas and other sections to match the higher power – for instance, the torque output triples. I believe we’ve succeeded in creating an engine with good basic qualities which make it receptive to such reinforcing modifications.

Honda :
Rally events contain a whole range of driving conditions, including lots of acceleration and deceleration, so in addition to absolute peak power, the mid-range output is extremely important. That’s why today’s rally car engine design typically adds turbocharging without lowering the compression ratio too much. What’s important is the balance between various performance aspects, such as trade-offs between power output at a certain rpm range, the quality of power build-up when the driver “steps on it,” and ample power even at low rpm. We are in the midst of seeking out the optimum combination of such power characteristics.

Takamitsu Sasaki :
I think the truth always holds that engines welcomed by rally pilots are engines that precisely respond to the drivers’ demands. I believe that by such measure the J-20A delivers superbly.

Honda :
As I said, easy-driving characteristics are now demanded even after the car is turned into a competition vehicle. We at SUZUKI are working on creating a sturdy, reliable base vehicle that well responds to such demand, including the chassis and engine developments that I’ve mentioned. Constructing of the actual competition machine out of the base vehicle, as well as entering the machine into competitive events, and the running of the racing operation itself, are tasks we entrust to SUZUKI SPORT, with which we have a long working relationship.
We’ve had this arrangement for quite a time, it’s brought us very good results in the JWRC over the years, and the latest vehicle development is proceeding smoothly, so we are happy to maintain this arrangement. Rally competitions are strictly production-body-based events, so we have to do our best to carry out our role of supplying the base car of the right quality in a timely fashion, so that development work at SUZUKI SPORT can proceed smoothly.
Of course, our policy for the WRC programme as a whole - such as the timing of our entry in events and how we promote our programme to our customers and news media around the world - need to be constructed for maximum overall effect in the introduction of SUZUKI’s new products. The timing of our race activities and basic planning will therefore always be subject to SUZUKI’s policy and control, and we will ask SUZUKI SPORT to work in tandem with our schedule and policy. SUZUKI and SUZUKI SPORT are not simply working together on this project; we will be moving closer to form a tight working relationship, almost like one company.

Honda :
In view of maintaining and strengthening SUZUKI’s standing in the global market, I believe we should express to the world our corporate “spirit of challenge” in a more clear form. We should express how the spirit of challenge is shared by each of our engineers. We should also use feedback from our WRC programme to make SUZUKI products more interesting; to offer products that make the customers driving our cars feel that “SUZUKI products have something different, something interesting.” It can include anything from a distinctly enjoyable driving feel to sporty visual impressions that complement such driving experience. In other words, anything that puts the spirit of challenge into solid form and solid impression. That way, we hope to make SUZUKI products more interesting to our customers, and carrying out such task is the big responsibility for me and all of the others at the Engineering Department.