‘Taken from ‘High Performance Imports Magazine’ issue No. 40, GT-R Special No.4’
The common myth with the GT-R is that many expensive changes must be made to the car’s basic configuration to get a decent power output and quarter mile time from it.
Nothing could be further from the truth. If you have a good-condition example (very important!), then getting genuine low-to-flat 12sec performance and 260kw at the wheels is only a handful of budget tweaks away. Here’s how it’s done.
Step 1 - Assess Its Health
Before doing anything to your GT-R, have a compression test carried out. Look for cylinder reading being even, around the 160psi mark. If you have this, then you will more than likely have a fairly solid base from which to work. If one or two cylinders are down, there’s a fair chance that the piston ring lands have been detonated out of it. Stop now and fix the thing. A healthy, near –stock car should have close to 175kw at the wheels, and be good for a 13.2sec quarter mile pass.
Step 2 - Turbochargers and Boost
The older and higher mileage the GT-R, the closer the turbochargers will be to their failure point. Both R32s and R33s have ceramic turbos, unless they have already been upgraded to Nismo spec.
It’s normally old R32 GT-Rs that dump the ceramic turbine wheel off the shaft. Later cars don’t have as much trouble, but they also haven’t had the ‘working out’ that an earlier car would have had.
Aim to run no more than 1bar of boost pressure through the standard turbochargers. A quick easy way to get close to this figure is to flick the restrictor out of the pressure like going to the factory boost-control solenoid.
The location of the restrictor is marked by a yellow band. Use some long-nose pliers, hook it out and enjoy 0.95-1.0bar of boost pressure. If you want more, then fit a bleed valve to the end of this line or wire up an electronic boost controller.
All up. For less than $300 (if you go the pneumatic route), you will have the target boost pressure. Don’t get greedy, as expensive turbo failure could result. At this stage you should already have around 200kw and 12.9sec performance.
Step 3 - Exhaust System
Search around wreckers for a stock GT-R car converter. They are of metal matrix construction a flow much bigger numbers than the ‘el cheapo’ things fitted at compliance time. Most compliance centers will have a good stock of them lined up that they have been removed from GT-Rs over the years. Get one, swap it for yours, whatever. You should be able to score the cat converter for no more that, say, $150.
There are also plenty of straight through performance exhaust systems available for GT-Rs from importers. They are common second-hand in Japan, so they end up being common here. I have seen systems such as HKS Super Dragers for as little as $750 second-hand. Budget around $1000 with the abovementioned catalytic converter, and for an all-up total of $1300 you will now have 215kw, 12.7sec performance.