Rocky Auto’s Rb30 Powered Fairlady Z

Composite materials and billet aluminum are probably the last two things you would associate with a vintage car, but for Watanabe-san of Rocky Auto these are the materials of choice when creating the most unique restorations we have come across in Japan. Actually scratch that; what Watanabe-san does is more like modernizations, making everyone’s favorite old cars from yesteryear feel and sound like something a little bit more up to date. This is probably the point when purists would cringe, but Rocky Auto isn’t out to please everyone…

…plus it’s not like Japanese vintage rides like the S30 Fairlady Z don’t get heavily modified as it is. Rocky Auto just does it with that little bit of extra flair, something that one of their latest project perfectly demonstrates.

We will get to the carbon fiber exterior a little further down, first up is the glorious sound emanating from under the hood that I want to concentrate on. There’s a certain something about the raspy straight six-sounds this S30 produces; the carbed throttle response is definitely there, but the induction and exhaust noises have a certain added quality. It’s hard to put a finger on what it is…

…until you have a look at the engine itself. The upwards-arched exhaust manifold is very S20-like, but the unmistakable shape of the cam covers means this could only by an RB26 head.

But it’s an RB26 head with a bit of a difference because it has been stripped of its electronic fuel injection and replaced with a triplet of 50 mm Solex carburetors.

The idea here was to mate the reliability of a modern engine, with the character that made these cars so appealing in the first place. Each of the six intakes have been fitted with a custom funnel, just the right length for good clearance in S30’s engine bay. Rocky Auto had to make the throttle linkage and the aluminum pivots too, as well as the spacer plate onto which the carburetors are mounted onto.

But it doesn’t end there. The RB26 head is bolted down into an RB30 bottom end, sourced and shipped to Japan from Australia. As Watanabe-san explains, the idea here was of course to be different but at the same time make the Z as fun to drive as possible. The 3 liters of capacity help low-end grunt, rewarding each prod of the throttle with instant torque, available all the way from 2,000 rpm. And with this being an RB it loves revs too, the 270˚ camshafts helping it develop just over 300 HP at about 7,000 rpm. It might not sound like much but when you consider this car hits the scales at 1,040 kg, that is ample performance for some serious fun on both the street as well as at the track.

The RB30 was located as far back in the engine bay as possible, sitting on custom fabricated mounts that are welded onto the fully restored chassis and custom front tubular subframe.

The Rocky Auto 46 mm 6-into-1 stainless steel manifold guides spent gasses towards the custom exhaust system, which has been designed to offer just the right amount of back pressure to match the engine’s performance.

Here is a closer look at the radiator Rocky Auto had Koyo fabricate, sporting a side-flow design and an electrical fan to keep the engine running cool even when stuck in those massive Japanese traffic jams. What we don’t see are the changes made to the driveline, which consist of a Nissan 5-speed transmission borrowed from an R32 Skyline, an ATS carbon clutch and a Cusco 2-way LSD. OS Giken supplied a close ratio conversion kit for the gearbox that shortens the first three cogs, making the Z pretty responsive and accelerative.

Prior to the build, the donor S30 chassis was thoroughly restored, rid of all rust spots and stiffened thanks to a dose of spot and seam welding. A custom multi-point roll cage was fabricated and welded in place, something that works wonders at further boosting torsional rigidity of the vintage shell.

What followed was some pretty impressive custom suspension work. A whole rear subframe was machined out of billet aluminum and bolted onto the chassis via solid bushes.

Billet front and rear suspension arms followed, again with no rubber or polyurethane bushing anywhere, metal on metal for the best possible handling and steering feel. Careful thought was given to the overall geometry, taking into account roll centers, camber and toe settings in order to give a very modern feel to this close to forty year old car. Rocky Auto adjustable coilovers were next, bolted down to reinforced top mounts front and rear.

The ride height has been set nice and low, or as low as you want it to be to have a functional and drivable car on the street. The choice of wheels couldn’t have been a better one, the Volk Racing TE37Vs boasting lightweight forged construction, a perfect addition to this modern take on the S30. The rims measure 9J by 15-inch up front, with slightly wider 10J by 15s at the rear.  Hiding behind the spokes of the wheels…

…are a set of R32 Skyline 4-pot calipers fitted along with slotted discs. At the rear single pot, slide-type calipers have been deemed more than up to the job.

And so we get to the body. Watanabe-san has never been one to shy away from using carbon fiber on his cars, and has always wanted to go a little wilder. This was his chance. The whole front section of the Z sports carbon fiber, parts like the bumper, the lower grille and splitter section and of course the hood.

The fenders and bolted on flares are also carbon, wet carbon to be precise. In an attempt to match the rest of the body 3M carbon-fiber-look vinyl has been added to the lower section, as well as…

…the doors, which have been left metal and thus required a similar finish. The side mirrors are carbon-look too and have integrated LED turn signals for yet another modern touch.

The carbon treatment continues rearwards…

…where the wrapped rear fenders meet the hatch, taillight panel and bumper all constructed in wet carbon.

You either love it or hate it, but whatever you think about this Rocky Auto S30 you can’t help but appreciate the amount of work and attention to detail that has gone into it.

Out on the road it simply looks fantastic, the carbed RB30 spluttering and backfiring on the over run…

…as it cruises the streets in Okazaki, where Rocky Auto is based.

The interior is a very focused place to sit in. Everything has been done to boost the experience and serve up an optimal driving position…

…which begins with a pair of Bride bucket seats and Sabelt harnesses.

Behind the Momo Corse suede steering wheel the aftermarket instrumentation has been neatly fitted inside the instrument binnacles of the stock dash.

The car has been stripped of the heater controls but you can manually “open the tap” and allow the hot radiator fluid to flow around the heating system and keep you nice and warm in the winter months. In summer you sweat.

Further weight was shaved off by replacing the door cards with a sheet of carbon fiber.

Watanabe-san is more than content at how his carbon S30 has turned out, his unorthodox approach to restoration and tuning building upon what made this Japanese classic so special. He has to keep moving forward however, so has decided to put the car up for sale so he can make space for his next project. Apparently it will involve an old Skyline and a VR38DETT. This, we will definitely have to see!

Rocky Auto 

-Dino Dalle Carbonare



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I need Videos of how it goes. Love the N/a approach also!


That might be the prettiest engine I've seen in a while. The triple carbs are well balanced with that very impressive exhaust header. Classy engine bay.


Most Awesome indeed!!


Great article, lovely car. Alas though I cannot stand raw carbon. Its just so ostentatious.  


My life would be complete if I had this and this in my garage.




oo yeeaaaa


 @Robjekt You can always paint it;)


 @lotusfd3s Coming...


so much love...


ftw!! triplet of 50 mm Solex carburetors..


I need to go change my shorts now............... My god that is awesome.




 @Dingma32 Better sound in this video


 @Dingma32 Better sound in this video:


One of the nicest cars from Rocky Auto !!


rocky auto makes most amazing cars. this may be one of my all time favorite of the fairladys


I feel I must comment here.
This is a great car feature mate. Pics are sublime, plenty of info (thought there can always be more), and the car itself is just beautiful. 


 @speedhunters_dino  @lotusfd3s wooooooooooooooo!!!!
this car is flawless btw.....FLAWLESS!!!!!!!!


Amazing achievement, that amount of work put into this beauty is astounding. Only thing I object to is the "carbon" wrap, that crap belongs on Civics with suicide doors.


Just a truly top notch creation, it really brings alive the lines of the S30!


The only detail that I would change is the use of faux carbon vinyl wrap.  A car like this one should not have any fake part on it.  Re-wrap it in flat/satin black and you have an absolute perfect 10...   instead of a 9.7...
Great shots BTW...


beautiful, pleaseeee do desktops of this one! <3


Wow!!... that's the direction i'm taking with my Z.... hopefully i will finish mine one day


and yes... some desktops will do the work... :)


I guess some wallpapers will be needed .... Pleaaaase ! :D


Only thing I'd change is that horrible fake carbon vinyl wrapping. Just paint it flat black or gunmetal!
I would imagine wrapping the body in fake carbon just adds weight instead of shedding it; that's gotta be what, 15-20lbs in vinyl?
And it looks like cookie.


Only thing I'd change is that horrible fake carbon vinyl wrapping. Just paint it flat black or gunmetal!
I would imagine wrapping the body in fake carbon just adds weight instead of shedding it; that's gotta be what, 15-20lbs in vinyl?
And it looks like dookie.


Only thing I'd change is that horrible fake carbon vinyl wrapping. Just paint it flat black or gunmetal!
I would imagine wrapping the body in fake carbon just adds weight instead of shedding it; that's gotta be what, 15-20lbs in vinyl? And it looks like cookie. The only thing that does is fool people into thinking the whole body is carbon.


Only thing I'd change is that horrible fake carbon vinyl wrapping. Just paint it flat black or gunmetal!
I would imagine wrapping the body in fake carbon just adds weight instead of shedding it; that's gotta be what, 15-20lbs in vinyl? And it looks like dookie. The only thing that does is fool people into thinking the whole body is carbon.


This car is so awesome! For me it gets a 9.8 out of 10.. because of the carbon wrap. I'd rather have painted it satin or gloss black so you won't know from the outside that some panels are from carbon fiber :)


This car is so awesome. If i was Watanabe-San, I wouldn't be able to sell such a car hahaha
wallpapers please!


Give credit where its due haters.  If you guys can build a monster of a concoction, then I'd let you fools say whatever you want.  Bunch of fcuken dreamers lolz.  This car ain't cookie cutter and you can just order everything in and just slap it together.  Once you brainless turds figure out how much is involved to build this monster, then speak.  I give this one a 10 out of 10.  Won't see another one built to this caliber for another decade or 2.


Who are talking to ? Nobody has said anything negative. Great car and post


headlights are fantastic....


Nice car, but sorry, most of the car's body looks like  carbon warp( like foliatec..), not real carbon parts.


 @speedhunters_dino rocking :D


 @RicardoCosta its cuz it is carbon wrapped (minus the wet carbon parts) ::headscratch:: di-noc = 3m carbon vinyl.  


how much?!


one of 10 best cars ever built.


 @dangina It's on sale at 13.5 million Yen


 @Aust55 The doors, roof and rear fenders are not carbon. Everything else is.


 @Aust55 The doors, roof and rear fenders are not carbon. Everything else is.


 @SuperDante Wallpapers are out now:)


 @AaronAlcaraz Haha, good find.  Very Japanese video




 @BC Thanks BC!


ZZZZZZZzzzzzzzzzzzz zz zz zz z z z z 


sin duda un muy muy buen auto!!! y el precio uuuf igual...  great car!! auto rocky  good job!!!!!!!




Seen a magazine article on this before, it showed the carbon stickers but not the totally reworked suspension parts. Great work for that alone Speedhunters! Still think a matching graphite pearl or similar would be better than the 3M wrap. Let the colour match in the distance and the carbon show off in detail. Can't get enough pics of the work people like this do on their handling.


Beautiful car indeed. But credit where it's due: that stunning rear suspension with the machined from billet arms are actually American, made by Arizona Z Car.


Splendid car. Those super sexy billet-machined rear suspension parts are actually American, made by Arizona Z Car. International sex then.


engine bay = mine's r34, body = bensopra r35, interior = racecar. should be some leather seats and carpets instead of brides. anyway, still liking it! awesome! awesome! awesome!


One of my favorites!




Lots of room for a greddy turbo and intercooler


Well im happy to say i recently bought some Rocky-Auto footworks parts (Mainly end links) for my Z and have to say they're really high quality. but somehow i don't feel their democars. I think it's ok to combine modern stuff with old curves, but at the end it's allways a bit "too much" imo what they do over there. i Prefer it simple and cool. The Z-chassis has enough attention - so putting more blingy stuff on it somehow kills it. howerver needless to say that the cars are really fast and sound like hell :)


This car is awesome! I love the idea of combining the old chassis with modern components. This is exactly the way I would biuld my own S30.


cool !!! it's so Amazing Fairlady !!!


"right amount of back pressure to match the engine’s performance"


I wish I get a full carbon fiber s30 similar to this but with a 20b rotary engine (hahaha.. I'm not a 100% sure about this but a rb26dett with a v-cam would be nice or a standard l24 would do) and a good interior so that it would be good for road trips....I like the dash of this one though..Something similar to the RTR-C probably.. 


does anybody know the original year of this z?




When a car has a ridiculously large exhaust, say 5 inches, there is not as much pressure of the hot gasses as there would be say a 3 inch exhaust, right? Some engines intake and exhaust strokes overlap for the slightest bit of time ever. If there is little to no back pressure, some of the intake mixture of air and fuel will escape and go right out the exhaust valve in that split second without being burned, thus wasting performance and power. If I am wrong, feel free to correct me.


@PhillyBrick nice job buddy =)


One of my Ink works of this vehicle is for sale.

Charlie villanueva

How were you able to put the wet carbon fiber wrap right next to the regular one... In the 16th picture... Doesn't the carbon fiber vinyl have to wrap around something?!?!???!?!?


woah!! I'm inspired


Anyone know were the carbon hood was sourced? I can't find one any where for my 260


Does anyone know where I can get those mirrors


Where are those mirrors from , really want them


AaronMuscato Seibon makes a wet carbon hood for like $600-700


xatkom yeah at first I thought someone made a freakin carbon car, but wrap is lame, the fenders are carbon it says. I'm getting the seibon hood but I'm painting mine orange to match.