Late-Blooming Hero | 40-Something D1GP Debutant, Shigehisa Sasayama’s JZX100 Chaser Under the Microscope!
Published : 2021/03/01 20:59 Modified : 2021/03/01 20:59
3.4L 2JZ produces 750ps!
Despite struggles in first D1 Grand Prix, secures points in two rounds
In the 2020 series of the D1GP, full of ups and downs as it was, one late-blooming rookie managed to secure points in two out of eight rounds at his first ever attempt. That man was Shigehisa Sasayama and his JZX100 Chaser which we introduce here.
Hailing from Chiba Prefecture, Sasayama returned to drifting at 39 years old (he is currently 44). In 2016 he took part in the D1 regional competition, in 2018 he moved to D1 Lights, and at the end of the 2019 season he gained the right to move up to a D1GP license. In 2020 he resolved to take part in the top-flight D1 Grand Prix series, with this JZX100 Chaser as his weapon of choice.
The exterior is fully kitted out in Kazama Auto Service’s Promode SS kit. In addition to this are generic arch flares front and back to deal with the extra steering angle and wider tires.
The engine is a 2JZ-GTE, and makes use of an HKS Capacity Upgrade Kit to bump displacement to 3.4L. Auto Service Mori, who are active in the D1 Grand Prix series, took charge of the build under the name “TEAM MORI”. A fully configurable LINK ECU keeps everything in order.
The turbo is a GCG G35-1050, and it provides 1.7 kilos of boost to help wring out 750ps. The pipe you can make out at the back of the turbo leads to the wastegate’s atmospheric dump valve.
The build does not neglect the necessary cooling parts to keep up with the high power and drift application. An intercooler nestles in the bumper’s air duct, with oil and power steering fluid coolers behind the front grille receiving fresh air directly to their cores.
The clutch is an ORC 1000F, which mates with a Samsonas 5 speed sequential dog transmission. However, in the Ebisu leg of last season the gearbox threw a cog for reasons unknown, and the team plan to use a Hollinger transmission in the 2021 season.
Like other D1 machines, the radiator is at the rear of the car. However, its placement is unique – instead of sitting behind the safety fuel cell as in most applications, it reverses this positioning, with the aim of making the car respond more sharply when initiating drifts and also improving traction. Apparently this worked extremely well, but the hot air from the radiator caused the fuel temperature to rise, leading to percolation issues. To deal with this, a heat shield and fuel cooler were added part way through the season.
The car’s footwork is based around Auto Service Mori’s DG5 set up. The spring rate is 28kg/mm at the front and 5kg/mm at the rear. Heyman Products’ “Saito Daigo 1500 Bariki SP Muteki Nakkuru (Daigo Saito’s 1500 Horsepower SP Invincible Knuckle)” increases the steering angle to the limit, with 35mm extended lower arms from the same company to combat rubbing inside the wheel well.
The rear differential is a Winters Quick Change, and houses an OS Giken Super Lock LSD. The rear suspension member is of the solid type. The arms get a rethink too: the uppers are from Ikeya Formula, with everything else coming from Kazama Auto Service.
The wheels are Enkei RS05RRs (9.5J +22). The tires are Valino; the fronts are Pergea 08Rs (265/35 R18), which Sasayama likes for their balance between lateral and longitudinal grip. The rears are Pergea 08RSs (285/35 R18).
The cockpit is a typical racing car affair, cutting away all unnecessary weight. The roll-cage is a one off piece, and allows the body a little flex. The driver’s seat moves backwards by a considerable amount to achieve the ideal front/rear weight distribution. Along with this, the steering column gets extended, and the pedals are replaced with organ style ones. The FRP dashboard is by TMS.
Sasayama took all possible measures to prepare for the 2020 season, with the leader of his old team, the famous “Ichihara Gundan”, Hiroyuki Maeda (5th from left) at the helm. In the role of spotter was former D1GP driver, Toyohisa Matsuda (3rd from right). Taking care of pit-lane duties was former D1SL driver Masayuki Gunji (far left), with Osamu Kamekawa (2nd from left) and Fumio Miyata (4th from left) as mechanics.
“Honestly, last year there were times when I was overwhelmed by the D1 Grand Prix atmosphere, so I’m hoping to really go after results in the 2021 season,” says an eager Sasayama. After making his D1GP debut in his 40s, we’re expecting great things from this late-blooming hero.
Text & photos：Daisuke Yamamoto
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