When Nissan originally released the GTR the company’s engineers thought it was perfect. What could any ordinary mortal possibly do to improve that beautiful V6 twin-turbo engine? The car was sculpted in a state-of-the-art wind tunnel and its gearbox, performance suspension, and body were optimized for performance. No wonder the owner’s manual on imported models carried this warning: “Disallowing illegal or unconventional modifications of the vehicle.”
Owners immediately and totally ignored the warning and soon one could find many buyers’ guides online with instructions and suggestions on how to upgrade your GT-R. Over time this this model became one of the top ‘tuner cars’ on the market and undoubtedly a darling of aftermarket car parts manufacturers.
Below we discuss some of the most popular Nissan GTR upgrades
Fit an ECU flash
The largest boost in engine power for this car can be gained from fitting an ECU flash, of which the most popular type is probably the Cobb AccessPort. This is an easy DIY solution via the vehicle’s OBDII port. The improvement in engine power is likely to be between 10% and 15%, but depends on the stage map you are running. The various stage maps depend on the modifications you have on your GTR, including intake, turboback exhaust, upgraded inter-cooler etc. Exhaust system
Another major upgrade is the exhaust system. The stock exhaust restricts power output to comply with regulatory requirements. The downpipes e.g. feature restrictive catalytic converters to control emissions.
Opting for a catless downpipe or a high flow cat will give you an increase of around 20 horsepower. For even more horsepower gain the muffler and midpipe should be upgraded. The bigger the diameter of the pipe, the better the exhaust flow and the more horsepower you will get. A good example is the 90mm Agency Power exhaust, which gives much better exhaust flow than competitors with only 76mm piping.
For top performance we recommend upgrading the midpipe, downpipes and muffler. To see what’s available from different suppliers, use Compare Parts – a great aftermarket car parts search engine that could save you a lot of time and money.
Upgrading the intakes, inter-cooler and pipes
Once you’ve upgraded the exhaust system and ECU, your next best option is upgrading the intakes to allow for better intake of cold air. You have to take great care with the air intakes, however, because if the diameter of the MAF pipe is smaller or bigger than the factory version, it could affect the ECU and cause the vehicle to run poorly. The majority of cold air intakes benefit the car by using a cone air filter that increases the air volume being taken in.
Apart from upgrading the air intake system you might also consider getting a bigger inter-cooler and upgrading the inter-cooler pipes to improve the flow of air into the turbo and help keep the turbocharger cool. Normally the inter-cooler and inter-cooler pipes are sold separately, so there’s need to purchase them at the same time.
Replacing manifold and fuel injectors
The next major upgrade on your list should be replacing the Nissan GTR’s standard intake manifold and upgrading the fuel injectors. By doing so you can improve the boost pressure and tune the vehicle to deliver even more power.
A particularly popular replacement manifold is the one sold by Boost Logic. This model boosts air flow from the intakes to the cylinder heads in a significantly less restrictive way than the factory-fitted version.
Which type of injectors you buy depends on the amount of extra power you want, but a popular option is to go with Injector Dynamics. A brief search at Compare Parts will give you an excellent idea of what else is available out there.
Upgrading the turbochargers
There is one more logical step if you are still not satisfied with the performance of your Nissan GTR: upgrading the turbochargers.
Depending on how much extra power you want from the engine, this can be achieved in two different ways. If you decide to stick with the stock engine internals, your best bet is to have the stock turbos modified. This is normally done by replacing the wheel to improve air flow. The second options is to embark on a major turbo replacement programme – which will of course mean new headers, and then re-building the engine.
Re-building the GTR’s engine can be accomplished by replacing the head gasket, rods, pistons and head studs. As a rule of thumb each 1 psi improvement that can be achieved equals about 10 horsepower. Another option is to upgrade the stroker motor where it takes the standard 3.8 liters and bores out the engine to a bigger displacement. This will not only give you a huge increase in torque, but it will also boost the engine’s power output.
