Team America World Time Attack – ARK Design’s BNR32 Skyline GT-R Intro Part 2
 
Badass unequal length A-arms all the way! Gary and Tyler working out some problems with the front suspension caused by the position of the front diff with the Hollinger gearbox.  The front diff is making our life hell as it intrudes on our lower control arm and steering rack placement.  Tyler and I had worked out the front end geometry in Solidworks but we did not have the entire powertrain yet.  Due to Eric's tight scheduling, Gary had to start on some parts of the fabrication before all the bits arrived.  So we had to improvise and change the design on the fly.  Our perfect on paper design had to be compromised for packaging reasons once the parts were in front of us.  As engineers we had to figure out the best compromise.  Our roll center is going to be 0.500 lower than design intent and we are going to have to settle for a little toe out under roll due to having to get a JDM Toyota MR-S steering rack to get diff clearance.  Our inner tie rod locations are slightly off but at least the rack will be in plane with the lower control arms. BTW, the front diff is an R35 GT-R unit that Kenji from Greddy donated. Inside of it will be an OS Giken R35 front LSD and Albins Gear custom ratio ring and pinion. The custom length, super strong, axles and CVs will be supplied by the Driveshaft Shop.
 
Gary assembles the left side suspension so we can judge fender fit and how the suspension will sit at ride height.  Chris from KW had to see this to figure out spring lengths and we had to rough out the shock motion ratio to finalize the mounting of the dampers.  You don't want the damper to be in falling rate or to have too non linear of a motion ratio so the damping will work better.  We are using a fairly long KW Motorsports 3-way remote reservoir damper to reduce angularity changes over the stroke which will keep the motion ratio more constant for better damping control and less spring kinking force.  The compromise is slightly more unsprung weight.  We were able to use the stock uprights which is saving a lot of fab time and money.  Eric fitted larger wheel bearings from the AWD V8 Nissan Cima to support the hubs and reduce the flex and brake caliper piston knockback issues that plague R32, 33, and 34's. This was the trick they used in Japan back when the BNR34 was active in Super Taikyu.
 
The keyboard tuners and JDM fanboi's are gonna hate this.  We dumped the beautiful RB26.  While the RB sounds wonderful and is a great motor for a street GT-R, going after time attack records isn't the street or vintage racing.  The RB is heavy and fragile at the kind of hp we will need to break records. The RB's long crank is subject to second harmonic whip and the oiling system is so so even when the engine is dry sumped.  Yes we do have a lot of experience racing high powered RB's.  Not 600 or even 700 hp RB's but mid 800's and we know what happens at those power levels. Team America's VQ35HR engine is over 100 lbs lighter than the RB and will live behind the shock towers making it a true front mid engine configuration.  The old car's RB26 was so far forward and so heavy that the car had a 60/40 weight distribution, worse than Annie Sam's FWD NX2000 race car!  We will be working to improve that considerably.  Gary sliced off the stock core support and built this cool tubular structure to support the engine and act as a lower subframe.  This is going to give awesome stiffness to the front end, get rid of about 50 lbs and make the car a lot easier to work on.  The white thing on top of the engine is a plastic rapid prototype intake manifold done by the Cosworth guys.
 

We are sporting some serious rubber up front.  18″ 295's Hankook Ventus TD tires on 11″ Volk wheels.  On the old car this sort of configuration with the stock R32 geometry resulted in something stupid like 5″ of scrub.  Not good for handling for sure.  Our new suspension has less than 15mm of scrub, just enough to generate good steering feel.  Not enough to make torque steer out of control or slide the tire sideways with just steering input to contribute to understeer. BTW, the Volk CE28N you see pictured here with the Hankook Ventus TD tires are borrowed from the Sierra Sierra EVO (thanks Richard).

 
We dummied up the fender mounting.  This gives you an idea of how low we are getting the ride height.  Look at other R32 race cars from back in the day.  They look like rally cars!  We were previously about 2″ higher than this even with short bodied struts and all the aftermarket roll center and bumpsteer corrector kits in place.  BTW, those off the shelf parts only go about 30% of the way to fixing the R32's front end geometry issues.  Bespoke all the way!  Now an R32 with a decent CG height and good aero lowness!

 

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