Guangzhou, China-based GAC unveiled its new compact SUV, the GS4, at the Detroit show in January. We got exclusive development details from GAC’s technical director, Zhongmin Xi
Guangzhou, China-based GAC unveiled its new compact SUV, the GS4, at the Detroit show in January. Powered by a 1.3- or 1.5-liter turbocharged I4 mated to a 7-speed DCT, it’ll be the second new GAC model to go on sale in a matter of months when it goes into production in April, following the launch of the larger GA6 sedan in December 2014.
“In the past the development of new models has taken us 36-38 months,” explains Zhongmin Xi, technical director for GAC, which also has JVs with Honda, Toyota, Mitsubishi and FCA. “However the GS4 was a very fast project, 24 months, just like a Japanese project. Programs are speeding up in China now and we pushed to get this done quickly. We have more in the pipeline, too; starting with the GA6 we are aiming to release a new car about every three months.”
The reuse of GAC’s ‘A’ platform, which first appeared on its GA3 small sedan (parts share is about 60%), was one way in which time was saved on the GS4 program, but not the only one.
“During the styling phase we took into account how the engineering would work with the styling,” explains Xi. “Then when it came to the structure, we did the manufacturing [engineering] simultaneously. Once the design data had been set we tried to go straight to production tooling, although we still needed prototype parts in some areas.”
Efficient use of proving ground availability was another way that time was saved. “While we were summer testing in China it was winter in New Zealand, so the winter ESP testing for GS4 was done in New Zealand.”
Xi (left) insists that the compressed timeframe won’t compromise the GS4’s quality, safety, performance or comfort. “So far during the GS4’s testing we haven’t encountered any major technical obstacles, although it’s always possible that something might come up,” he says, adding that NVH is always a challenging of development: “Even a month before the SOP of the GA6, we were still fine-tuning the gearshift.”
“Hundreds” of cars have been built across the prototype and pre-production phases. Xi says there are 10 major gates whose requirements a new vehicle must pass to move on to the next phase.
Most of the GS4’s testing and development has been done in-house (GAC has its own test tracks) and in China, but external suppliers contribute in some areas. “We take care of most of the R&D but we can never do everything by ourselves so we integrate the best resources from around the globe,” Xi explains. “For example, Bosch helped us to tune the Generation-9 ESP system. But when it comes to the performance requirements and verification of those requirements, we make the decisions. We let our partners know what level we are trying to reach. For suspension tuning, we require our suppliers to come to us [to do the work] so that it meets our requirements.”
The final level of sign-off comes from GAC’s company leaders, who test production-ready cars just before SOP.
February 26, 2015
