Mulsanne's Corner: Hasegawa's 1/24 Nissan R91CP

Hasegawa's 1/24 scale Nissan R91CP & R92CP
Kit #s HC31 and 20404

Images copyright Michael J. Fuller
Text copyright Michael J. Fuller

It's been 30+ years since we've seen anything new from the GTP/Group C era from one of the big plastic injection molding companies. So you can imagine my excitement when Hasegawa announced a Nissan R91CP in 1/24 (kit # HC31)! The heyday clearly was the late 1980s, early 1990s, for 1/24 sportscars when Tamiya and Hasegawa each were issuing kits of the Porsche 962C, Mercedes-Benz Sauber C9, Jaguar XJR-9, etc. But then it all stopped. But now, all these years later, we finally have the NISMO designed Nissan R91CP (and R92CP!).

The NISMO cars were designed by Yoshi Suzuka for the Japanese Sport Prototype Championship (JSPC), the All-Japan national series for Group C cars. For the most part these NISMO cars raced exclusively in Japan (the exception being the single entry R90CP at Le Mans in 1990 and the single entry R91CP at Daytona in 1992). In 1990 Nissan entered the JSPC with the Nissan R90CP, an extensively modified version of the Lola-designed Nissan R89C. Yearly developments by NISMO would see them field the R90CP, R91CP, and R92CP in respective years. But the R90CP was more than a mere development of the Lola designed R89C; Nissan's aerospace facility in Ogikubo would produce replacement tubs and approximately 70% of the R90CP was redesigned. The respective year's R91CP and R92CP would be 100% Nissan designed and built.

Digging into the kit, its body work actually clips off at the real car split lines; the nose comes off and the tail section comes off. Shown here assembled to show off how seamless and well aligned it is.

Taking the nose off reveals tub and front substructre/radiator structure detail. The front (and rear) suspension is detailed too.

The louvers are actually open. So no more dicey Dremel operations trying to open up solid louvers. Or NACA ducts for that matter as they're all opened up too.

Engine bay area and we have correctly shaped fuel cell area at the back of the monocoque. The intercoolers and turbos are all molded, however the only thing Hasegawa didn't do was replicate the engine. However, mechanically, aft of the firewall, there was effectively no difference from Nissan R89C through to the Nissan R92CP. And with that in mind I've acquired another Tamiya Nissan R89C kit to steal the engine out of as Hasegawa gives you the gearbox and bellhousing, turbos, and intercoolers. It should just be a matter of alinging the Tamiya VRH35Z engine with the Hasegawa turbos and gearbox/bellhousing (which will require cutting off the gearbox/bellhousing from the Tamiya kit's engine as it's all integral). Add this to my never ending list of model projects...

The underfloor has some very nice detailing, things that usually get ignored such as the various rub blocks and wear strips have been included. Yoshi Suzuka (the designer of these cars, as well as the Nissan GTP ZXT and Nissan P35) spoke with those present when Hasegawa scanned the car and was told they did not scan the underfloor, given the difficulty of raising the car and producing a good scan considering the limited raised height. And for the time being I can't completely vouch for the accuracy of the shape of the kit's underfloor; Suzuka indicated some differences though didn't elaborate. The limited photos I've seen of the R89/R90 family's underfloor indicates that the outboard leading edge tunnel wall tracks slightly outboard going forward in a muted bellmouth fashion. How that relates to the NISMO developed cars I don't know.

While not used on the R91CP, a gearbox cover comes with the kit. When I asked Yoshi when he introduced the cover he replied that he couldn't recall when it was done but was reminded that he actually laid up the original part, "I guess it was a trade off between aero advantage and transmission cooling that I did not have time to test or information, and left them open (originally), and made cover later after we knew the transmission temperature, after racing the car." Hasegawa bundled some parts for the up coming R92CP kit on the same sprues as the R91, hence its inclusion here.

The rear wing mainplane and flap aren't slabs, they're actually wing-shaped!

Another open louver, this one buried within the intercooler exit duct that emerges just ahead of the rear wheels.

The brake calipers are separate from the discs. Those of us familiar with Tamiya's Group C kits from the late 80s are used to combined disc/calipers which tested your painting skills, so this is a nice change of pace.

Another nice detail, the independant/separate roll over cage. Typically you'll see exposed sections of this molded integral to the rear firewall with no hint at all of the overhead bars. Mine arrived broken, however Plaza Japan contacted Hasegawa for me and dispatched a replacement.

Nicely detailed gearbox and bellhousing.

Now you'll ask, but what about the Hasegawa R92CP? With both kits in-hand, the only difference I note (other than decals, oh, and wheels) is that the R92CP kit (kit # 20404) has the tire cooling slot above the rear wheel fender on the engine cover (Yoshi Suzuka sent this graphic denoting the purpose of the various inlet ducts on the R90CP thru R92CP series cars. It's somewhat counter-intuitive inasmuch as the one we always thought was a turbo inlet, the centerline engine cover duct, isn't--make sense as the turbos are mounted low and outboard on the R89/R90 and that wasn't changed on the R90CP-R92CP). Everything else is identical in the R92CP kit. Which is odd, because the primary identifier of the R92CP was the very large front fender exit vents. But wait, there's more! Those parts, the long wisker vents themselves, are actually on the parts sprue (sprue G, parts 1 & 2)! However, they're grayed out in the instructions and not used. Furthermore, the front nose that comes with the R92CP kit is the exact same louvered nose that comes with the R91CP, so no retro-fitting the wisker vents onto the nose that comes with the kit. However, all this does seem to mean is that there's another kit in the works. Though I'm particularly puzzled what they'd call it!