I bought my car from the second owner in 1998 with about 37K miles on its odometer. My plan was to have a nice, stock GN that I could drive on warm summer days. I did manage to make it to the track and run a few 14.5s at about 95 mph. That was done with bone stock parts, including the restrictive stock air cleaner assembly and catalytic converter. It was at the 1999 GS Nationals that my good friend talked me into buying a K&N cone filter and eliminating the stock air cleaner. I also removed one screen from the stock mass airflow sensor. With no other mods, the car went 13.7 at 100 mph. This was at 15 pounds of boost on street tires.
The next year, I decided to upgrade the turbo to a TA49, install a Terry Houston downpipe, adjustable fuel pressure regulator, 009 (42.5-pound) injectors, and a Joe Lubrant race chip. I bellmouthed the throttle body and intercooler inlet with a grinder, and I bought a set of 26x10.5-inch M/T ET Drags at a swap meet. I also upgraded the weak stock valvesprings with new LT1 springs from the local parts store. Traction issues and poor tuning on my part kept me from going any quicker than 12.1 at 110 with a 1.95 60-foot. I unhooked the sway bar, and all of a sudden it hooked, but now I had a new problem. The car developed major body twist while I was trying to build boost at the line. The 60-foots improved to the 1.75 range and the car went 11.80 at 113mph, but my scan tool was telling me the car was running very lean at the end of the track. My stock fuel pump just couldn't keep up.
My next purchases would be one airbag, a new XP fuel pump from Quad Air, and a fuel pump hotwire kit. I came across a good deal on a TA61 and an old Action Fabrication 15-row stretch intercooler. I made a homemade cold air kit from some 4-inch flexible hose and relocated the cone filter behind the front bumper. My stock throttle body was replaced with a 62mm from Steve Monroe out of Oklahoma. I also wanted to get a taller tire to try to bring the rpm down at the big end of the track. It seems like these stock motors are out of steam at around 5,000 rpm, so another buddy of mine found me a slightly used set of 28x9 ET Drags. With everything done, my next time to the track would net me a best of 11.55 at 115. This was at 25 pounds of boost on a rich tune. I was just happy knowing I wasn't running lean at the end anymore.
With this combination, I've been able to tune it down to consistent 11.30s at 118 mph, with a best of 11.23 at 118.38. This was done at 29 pounds of boost, still running a bit on the rich side. I make all my passes on stock GN wheels and through the exhaust. I also run the stock tranny and D5 converter. Since these passes, I've added 28-spline Moser axles, an Eaton posi unit, and HR Parts & Stuff rear control arm bushings. The 60 foots are in the 1.55s. I think with a little more tuning and lighter wheels, the car will definitely run in the 10s. I'll find out this summer. Knowing what I know now, the fuel system is the first thing I should have done. I kinda did everything backwards. At least I didn't blow it up "learning!"
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