Dai Yoshihara’s Two Week Wonder, GT Channel’s Time Attack 350Z


Dai Yoshihara's GT Channel 350Z Time Attack Car

Dai Yoshihara’s Two Week Wonder, GT Channel’s Time Attack Nissan 350Z

By Mike Kojima

Pro Drifter and Formula D ace Dai Yoshihara is used to working on tight deadlines. Perhaps you have read our story on his 8 day wonder S13 that we covered in detail. To tell this story, and appreciate it, you have to rewind to a week before the 2009 SEMA show. Dai got the request from his long time supporters, The GT Channel to build one of their show cars into a time attack car for Source Interlink’s 2009 Super Lap Battle Finals. The folks at the GT channel had a Nissan 350Z roadster that had been originally built as a SEMA show car two years ago, it had been gathering dust and the GT Channel wanted to do something with it. Dai was contacted and a deal was struck to give him the car to build into a time attack car.

After much thought it was decided to build the car for Super Lap Battle’s Street Class. This was because Falken Tires, Dai’s main sponsor currently, does not make a DOT R Compound tire and their experimental racing slick is not currently available to the public. The clock was started with two weeks to go before Super Lap Battle with one week of that time being eaten up by the SEMA show.

With this tight schedule Dai knew he had to assemble a crack team to get the car done. He contacted Costa Gialamas of GTI Motorsports to take the lead in car construction. Costa is Rhys Millen’s crew chief and Dai had a good relationship with him from when he used to drive for RMR. Costa would have to do most of the work alone for the first week as nearly everyone else involved would be at the SEMA show.

Seibon Carbon 350z roadster
Seibon carbon fiber parts were responsible for shedding hundreds of pounds from the roadster’s porky 3,600 lb frame.  GTI Motorsports roll cage is a work of art and stiffens the flexy roadster unibody.

Costa wasted no time, first stripping the porky 3,600 lb Z roadster of all excess parts that were not needed or required for Street Class. The air conditioning system was removed but the heater stayed as the rules require. The sound insulation, convertible top and cover were removed. A lot of unneeded plastic parts and finishers were also removed. In all, over 300 lbs was shed from the car. Costa then fabricated the roll cage using 1.75″ 4130 condition N chrome moly tubing with a 0.095″ wall thickness. Condition N stands for normalized or the non solution heat treated condition of tubing.  Normalized tubing does not develop stress when bent and does not weaken in the welds heat affected zones. The cage was tig welded using ER70S mild steel filler rods.  With this the weld fillet is the same harness as the tubes and the thinner tube will fail first if the cage is overstressed.  The cage is attached to the car’s frame rails using boxed plating. This is the most effective way to mount a cage.

Dai Yoshihara time attack 350z
Good teamwork is essential for any racing effort!


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