For those who came in late, technical explanation here.
The GTS-R version of the HR31 Skyline was developed in 1987/8 to go Group A racing with.
It is purely an homologation special of which 800 (odd) were made.
The Group A rules of the time dictated that any car could be raced, and for go faster bits, a minimum of 500 homologation specials had to be made.
Which is why we have the Ford Sierra Cosworth RS500, BMW M3 evolution and various other rare hotted up models.
For Nissan it was the Nissan HR31 GTS-R.
The road car came with different seats and upholstery to the standard GTS.
Different aero consisting of the GTS-R specific rear spoiler/wing
and a fixed chin spoiler shaped much like the flip down autospoiler.
Under the bonnet, the changes are a fair bit bigger.
The engine is denoted RB20DET-R and came with -R specific red cam covers.(a different red to the standard engine)
The -R engine came with a much bigger Garrett T04E turbocharger,
seen here in comparison to the standard T03 turbo.
This was hung off a tubular exhaust manifold.
The car also had a unique crossover pipe, larger 3" piping to an intercooler at least quadruple the size of the standard one.
This fed a larger throttle body and was controlled by a -R specific ECU.
The -R engine also ran a lighter flywheel.
The 2 things I have that are genuine GTS-R parts are a complete engine, and now the rear wing I have lusted after for some years.
I now consider the car complete in a hardware sense.
It has all the good bits I want.
Afterburner tail lights.
Now will come the slow process of making it look good.
I still have a plethora of stonechips, carpark dings, and scratches in the paint.
And it is still a 24 year old car with quite a bit of electronics.
Luckily you can still buy a fair bit of stuff ex stock Nissan but Nissan has stopped making new stuff for the R31 as of 2010, so things are going to start getting hard to get.