posted on July 16, 2014 14:16
NX GTi-R: The Search for Traction
Searching for a needle in a haystack would be easier than trying to find a good limited slip differential for my car, a 1992 Nissan NX1600. Before I swapped engines, I installed a Phantom Grip Limited Slip Differential to improve traction with the GA16 drivetrain. Then and now, there was not another alternative for the GA16. It worked reasonably well and assisted in making me feel better about my car. Mike Kojima has indicated that a Phantom Grip in conjunction with the SR’s OEM viscous Differential worked well. After a few years of searching for a solution to my traction issues after my SR20 swap, I began to think that might be the direction I needed to head.
The GA16DE engine deserved more credit that it ever got. Lots of torque. Very durable. But when it came to bench racing and talking about horsepower, there was simply nothing to say. I had done virtually every modification for a naturally aspirated engine that was available and I still didn't have 100 whp!
Then I swapped the engine and installed the venerable SR20DET from a GTi-R into the NX. Along with the swap an Infiniti G20 transmission, 1999 model year, was installed into the car. This transmission has an OEM viscous Limited Slip Differential, however, with the power that the GTi-R engine is putting out it may as well be an open differential. Nothing but wheel spin in the corners. Little bumps on the track would cause wheel spin and chirping the tires in third gear under acceleration. Seriously! The boy racer in me loved it but the old man in me was irritated that I was losing so much rubber every time I went through a corner. Rotating tires, flipping them on the rims, this all became a regular part of a weekend of racing rather than a mid-season chore. The racer in me was frustrated that I had built a straight line car. The kind that irritated me while driving a momentum car, as they would fly by me on the straights but then would hold me up in the corners. The car was faster, but not by the degree I wanted to see. At Canadian Tire Motorsport Park the car with Hoosier R6 205 50 15s ran 1:47 with the GA16DE powerplant. At the same track the same fast driver, my daughter Katie, took the car with Toyo RA1 225 45 15s around at a time of 1:40 with the SR20DET. That is a good jump, but with a 200 whp gain I wanted more! You have to be in the car to realize how much speed is being lost exiting corners. It simply cannot find traction.
The SR20DET from the Nissan Pulsar GTi-R has an awesome torque curve and great horsepower. At 12.4 lbs of boost it registered 297.3 WHP. This dyno reads slightly high, but don't let that fool you. This power is real. The car pulls incredibly well. First gear disappears in the blink of an eye.
NISMO and Quaife built great LSDs for the Front Wheel Drive Nissan platform, but that was back in the day. I have owned my NX since back in the day, December 31, 1992 to be precise, but when I started upgrading it over a decade ago I discovered that the major aftermarket companies had already started winding down their support for this platform. I have not been able to see as clearly as others and this car is still in my garage and still getting, according to my wife, a lot of my money. Pamela, my wife who loves me dearly but wishes I had never seen a racetrack, has even suggested that I consider another car. Maybe some day, but not yet. Perhaps part of the allure of this car has been the search for parts? Being the underdog? Or simply an attachment that over two decades of ownership provides? There is no question, I have been scouring the Internet for quite some time in the hopes of finding that elusive part. Early on in my search I met (online only, as I live in Canada and have not been able to connect in person) Mike Kojima, Greg Vogel, Scott Higashi, Wes Dumalski, Greg Amy (to name a few) Nissan gurus who have helped me enlarge my search. I laugh when I think of my early search questions. For example, on the SE-R-List (which is like FaceBook for nerds and geeks who cannot let go of the past, because it is from the distant past) I posted a question about getting better springs for my seat because, after buying and installing a Ground Control Coilover setup with KYB AGX struts and Eibach springs, my head kept hitting the roof when I encountered a bump. Mike K responded with a loud “Raise that car! Raise that car!”. The shop that helped me with the car had it slammed to the ground and I did not know better. I was riding the bump stops constantly and that meant my head was constantly hitting the car’s roof. Needless to say, I raised the coilover settings. There are also many good friends that I have made here in Ontario that, if I had not had this car, I may not have met and forged such good friendships. Getting back to differentials, I have called companies that made plate differentials for other Japanese automobiles in the hope, always misguided, that maybe they would want to make me one. I simply could not afford to buy ten or fifteen LSDs just so I could get my prize.
Where do you store your parts? I have mine in my garage, my garden shed, my fruit cellar, and even my neighbour's garage (yes, I have great neighbours!) Here's a shot of my fruit cellar where I have a couple of hatchs, a hood, a couple of doors, T-roof panels, window glass, lots of interior bits, and even the OEM rear sway bar off of the GA16 powered NX. Piled on the top are a couple of noses and at least one rear bumper. Like many owners of Nissan's quirky NX, I've owned several (red, blue and two that were white).
January 30, 2013 I followed up on a lead about a used Nismo LSD being for sale. I discovered that it may be, but that the owner was in the midst of a number of non-car related things and would not be able to remove it for some time. We chatted via email a bit over the next few months but life caught up with both of us (my money went to a trip to New Zealand and Australia to visit my daughter), the LSD still was in the car, and I figured it was not going to happen. Many intriguing things happened next as life moved on, but still no LSD in my car.