The 2014 NASA NW season went very well. Finished with 7 first place finishes and 2 second place finishes, set new personal bests at every track in the series, and set a new track record at the Ridge… twice. Now that NASA is splitting the National Championships into an East coast and West coast event and the West coast event is at Sonoma this year, I decided to enter the competition to gain Nationals experience.
Due to budget and time constraints, I decided at the outset to make no changes to the car and perform very modest preparation. The car has been working flawlessly this season. The new Urge Design AP Racing brakes with Hawk DTC-70 pads have held up to some major abuse and are still going strong. The addition of the Radium Fuel Surge Tank cured the fuel starve issues and oil pressures are looking great.
To get my championship classing paperwork in order, I decided to run a new dyno compliance test to get official numbers. The last time I was on the dyno was during an event at PIR when MCE brought their mobile dyno service. MCE is typically the official dyno for NASA events. The S2000 registered 369 whp. During the off season, I replaced the 3″ HKS single exhaust with my old exhaust which was the factory midpipe and resonator with a single exit Magnaflow muffler. The system was 2-3/8″ diameter throughout. I made this change as the HKS was getting too loud after the resonator exploded and was replaced with a straight section of tubing. I also removed some weight mostly in the form of trim (carpet, sound deadening, sound system, air bags, etc) to get closer to the adjusted 8:1 wt/pwr ratio allowed in TT2. In October, I dyno tested at Service Pro in Nooksak Washington and recorded 319 whp. Datalogs showed that the car was running fine and making normal boost. The peak power dropped off at high rpms which was a surprise so I attributed it to the small diameter exhaust being a restriction.
Note – I ran all 2014 season at this power level which means I was about 340 lbs overweight or 40 whp under powered. That put me at 9.174:1 adjusted wt/pwr which is TT3 territory.
I began weighing my options and quickly realized there was no way to remove 340 lbs without substantial cost and time. This would also require re-tuning the suspension and I didn’t have time for additional track testing. Dramatic weight removal did not comply with the proclamation of “no major changes”. Another option I considered was to add a little weight and run in TT3 where it is much closer to the class minimum. I asked some competitors about the validity of the two dyno’s in question. Dynojet’s should be very consistent by design but the feedback I received was that the MCE dyno when at Portland was reading about 20 whp high in the 300 whp range. The Service Pro dyno was suspected to be 10 whp low compared to some other NW dynojets. With this lack of confidence with the dyno numbers, I decided to fabricate a new 3″ exhaust that should give me peak power back and hope that the Nationals dyno reads somewhere in-between.
So… despite the mantra of “no major changes”, I decided to fabricate a header-back 3″ stainless steel exhaust from scratch. Using mandrel bends and a lot of measuring and cutting and finally backpurging and tig welding. Much quieter than the HKS sans resonator and fairly light at 24.2 lbs. Of course, I finished this exhaust on Sunday and we were leaving on Tuesday. There are always last minute projects no matter what. By the time I finished the exhaust, the sound restrictions for the event changed from 100 db to “no sound limit”. Could have just thrown the HKS 3″ on there.
Holding in place with Zip Ties… not just for drifters.
Not exactly beautiful but should hold together and make braaap sounds.
Temporary zip ties replaced with tubular hangers.
The rest of the preparation consisted of mounting up a sticker set of Hoosier A7’s, loading some used A6’s, used A7’s, and Hoosier Wets – just to make sure it doesn’t rain. The only spares packed up were brake rotors and pads and the old 2-3/8″ exhaust just in case the dyno reads super high and I need to kill some power… or if my new and untested exhaust breaks in half. Next stop:
Sears Point Infineon Sonoma Raceway!