The values of old Nissan Skyline GT-Rs continue to soar, especially now that more and more examples are becoming eligible for import into North America.

As a result, the cars are becoming more sought after by collectors, though given the nameplate's popularity with the tuning scene, finding original examples in prime condition is rare. That's where Nissan, more specifically the automaker's Nismo performance arm, can help.

Due to popular demand, Nismo has been developing more and more official replacement parts for the previous R32, R33 and R34 generations of the GT-R. The latest is a titanium exhaust kit that helps save around 28 pounds from the curb weight. The kit alsos reduce exhaust back pressure by about 7%.

Each exhaust kit is unique to the model it's designed for, and like most titanium setups the price isn't cheap. The kits for the R32 and R33 GT-Rs are priced at 726,000 yen (approximately $6,300). The R34 GT-R kit is priced at 737,000 yen (approximately $6,400).

Nismo titanium exhaust for Nissan Skyline GT-R (R32)

Nismo titanium exhaust for Nissan Skyline GT-R (R32)

Nissan Skyline GT-R (R32) with Nismo titanium exhaust

Nissan Skyline GT-R (R32) with Nismo titanium exhaust

The list of parts Nismo offers for classic GT-Rs now numbers in the hundreds, and some of the parts are made using unconventional methods. You can even purchase whole engines if needed.

However, for buyers with really deep pockets, Nismo offers a complete restoration service where a customer can have their car stripped to its bare structure, repaired if necessary (with stiffness and dimension measurements taken), and even coated in rust protection before a full repainting and rebuild.

There are also options for owners on smaller budgets. For example, the restoration can focus on just one element, such as the powertrain, drivetrain or interior. For each restoration, every part involved is inspected and tested, after which it is either refurbished or replaced by an official part. A detailed log of all the work done, along with part numbers, is included in the process.

Nismo also offers as part of the service a chance for owners to upgrade their cars, for example from a standard GT-R to a V-Spec or V-Spec II Nur. This will depend on the availability of parts, Nismo said.