OS Giken Power: America’s Most Exotic 240Z
Just An Inline 6

It’s an early January Friday afternoon in San Jose, California, and I’m sitting in the shotgun seat of a 1971 Datsun 240Z that’s stopped at a traffic light. A 240Z that just a few moments earlier completely blew my mind.

Z-Car-Garage-196 copy

In fact, my body is still recovering from the acceleration I just experienced; my adrenaline slowly heading back towards normal levels. This early 1970s Japanese sports car is unlike anything I’ve ever encountered before.

Z-Car-Garage-112 copy

A guy in a BMW 1 Series pulls up beside us, likely having caught a glimpse or heard the sound of the Z running through the gears. “What have you got in that thing?” he asks with a mixture of confusion and amazement.

Z-Car-Garage-197 copy

“Just a little Datsun inline-six,” replies the driver of the Z, Mr. Rob Fuller from San Jose’s Z Car Garage. And before the Bimmer guy has time to inquire any more, the light turns green and we’re off again in a screaming symphony of naturally aspirated music. Rob was not lying to Mr. BMW, and that’s the beauty of the whole thing.

Z-Car-Garage-203 copy

Of course, this shiny black Datsun is completely unlike any other L-powered, naturally aspirated Datsun in America. In fact, there are just a handful of cars like it anywhere on the planet.

Say hello to the OS Giken x Z Car Garage 240Z.

Z-Car-Garage-103 copy

This car, officially unveiled at last year’s SEMA Show, is a project that’s been a long time in the making; a build that would become the first ever Stateside application of OS Giken’s legendary TC24-B1Z twin can cylinder head for the Nissan L-series engine. Even in Japan, the OS Giken head is about as rare (and as expensive) as an engine part can get. It’s a component that feels more like a unicorn than something you actually see, but here it was in the flesh and ready to rock.

Z-Car-Garage-189 copy

This collaboration is something that Rob wanted to happen for a long time. Once he caught wind that OS Giken was considering bringing the TC head to the US, Rob knew his shop had the experience and vision necessary to build and showcase this exotic powerplant to an American audience.

One Of A Kind
Z-Car-Garage-149 copy

Rob also knew he had an ideal car for the project – a 1971 240Z owned by his friend and long-time Z Car Garage customer Gary Stephenson. The plans were originally to give Gary’s S30 an RB swap, but when the OS Giken opportunity came along it felt like the perfect match.

Z-Car-Garage-100 copy

In the summer of 2015 the dream started to become a reality; the TC24 head arriving in the US in preparation for the SEMA build. But it would take a whole lot more work than just putting the head on an L-motor and calling it a day.

Z-Car-Garage-97 copy

The engine itself uses a Rebello-built 3.3-liter L-block with plenty of displacement to pair with the high-winding OS Giken cylinder head conversion. From the very beginning the plan was to go with a more street-friendly powerband as opposed to an engine that’s only happy at upper-range RPMs.

Z-Car-Garage-104 copy

The car breathes through a set of three 50mm Solex carbs which are typically only used in race applications but are very well matched with the OS Giken head.

Z-Car-Garage-101 copy

And on the other side of the motor you’ll find a one-off, equal-length race header connected to a custom 3-inch stainless steel exhaust system.

Z-Car-Garage-115 copy

The numbers the motor makes in its current form are downright astonishing: 376 horsepower to the rear wheels with 281 foot-pound of torque, all the while behaving without the finicky nature you might expect from a fully-built N/A straight-six that’ll scream up to 9,000rpm and beyond. And it’s not just the power, but the way it makes it. It feels just like a 240Z should with decent mid-range punch and power that continues to build at upper RPMs. Just multiply the power and the sensations several times.

Z-Car-Garage-152 copy

The engine is mated to a 240SX 5-speed gearbox which handles the power well. The TS3A clutch and flywheel also comes from the OS Giken catalog, as does the Super Lock LSD inside the R180 rear differential.

Exotic Yet Traditional
Z-Car-Garage-195 copy

From the beginning it was important that the car be able to handle all the additional power, so you’ll find a set of Z Car Garage adjustable coilovers, along with upgraded sway bars, T3 tension rods and Arizona Z Car rear lower control arms.

Z-Car-Garage-204 copy

There’s also no way the original 240Z brakes were going to work with 376 horsepower, so they’ve been rightfully upgraded with one of Z Car Garage’s popular 4-piston/328mm big brake kits.

Z-Car-Garage-110 copy

The wheels are Panasport Racing C8s that measure 17×8 inches on all four corners and are shod with 255/40R17 Bridgestone Potenza RE-71Rs.

Z-Car-Garage-153 copy

Despite the width of the wheels and tires, they tuck perfectly under the non-flared 240Z bodywork for a very subtle and mature look, particularly when matched with the Nissan Super Black paint.

Z-Car-Garage-146 copy

In most ways the Z looks just like a factory restoration, and that includes the largely original-appearing interior which cleverly integrates a custom rollcage with low profile door bars.

Z-Car-Garage-151 copy

The steering wheel is a factory wood-rimmed Datsun piece and the original seats have been swapped out for Recaro Specialist recliners that are very subtle in their appearance.

Z-Car-Garage-148 copy

And speaking of subtle, check out the window cranks which actually operate the power windows with a simple nudge up or down. This is just one of many super-cool touches around the car.

Z-Car-Garage-165 copy

The S30 Z is a vehicle that’s been seen countless times on Speedhunters, and in many different forms. But I can honestly say there’s nothing like this one. It really is the perfect wrapper for one the most impressive tuning products to have ever come out of Japan.

Z-Car-Garage-199 copy

The OS Giken x Z Car Garage 240Z manages to be incredibly capable while also staying true to its Nissan N/A inline-six roots. There’s no fuel injection and no turbocharger, but its performance numbers will put many high-tech modern cars to shame. And at the same time the engine itself is so rare and exotic that a Ferrari V12 might look tame by comparison.

It’s a classic Japanese sports car unlike anything I’ve ever experienced before, and also one that I’ll never forget.

Mike Garrett
Instagram: japanifornia_media

OS Giken X Z Car Garage 1971 Datsun 240Z

Max Power: 376rwhp, Max Torque: 281ft-lb

Rebello-built 3.3-liter L-series block, OS Giken TC24-B1Z DOHC cylinder head, 3x Solex 50mm carburetors, Z Car Garage custom equal-length header, Z Car Garage custom 3-inch stainless steel exhaust system, Nissan Competition oil pan, MSD 6-AL ignition, Koyo race radiator

240SX 5-speed manual transmission, OS Giken TS3A clutch & flywheel, R180 differential with OS Giken Super Lock LSD, Ermish Racing CV axle conversion kit

Z Car Garage adjustable coilovers, T3 tension rods, Arizona Z Car rear lower control arms, Motorsport Auto sway bars, Z Car Garage big brake kit with 4-piston calipers and 328mm rotors

Panasport Racing C8 17×8-inch, 255/40R17 Bridgestone Potenza RE-71 R tires

Fully restored exterior, one-piece rear bumper, JDM taillights, Nissan Super Black paint by William’s Auto Body

Original restored interior, custom rollcage with low profile door bars, Recaro Specialist seats, carpet & trim by Bascom Trim & Upholstery

More Datsun related stories on Speedhunters

Cutting Room Floor
Z-Car-Garage-109 copy
Z-Car-Garage-113 copy
Z-Car-Garage-140 copy
Z-Car-Garage-187 copy


Comments are closed.


by Oldest
by Best by Newest by Oldest

Now THAT is how a roll cage should be done in a classic.  Great to have the increased safety out on the road, but you barely notice it's there.

Would love to hear that engine being wound out BTW.


No sound clip??!!?? :L


CharlesChris15 Seriously! I was expecting at least a short video clip...


The car is simply breathtaking, it's a damn shame we don't get an exhaust note :(




@zbob  way to come through clutch


Here is a different video I shot while riding shotgun in the car a few days after SEMA. I think you can better hear the "true" sound of the engine (even over wind noise) in this clip PLUS it has the car running around with its "show hood" on.


StevenFallas Perfect!


JDM_Luca My feelings exactly :)


Coryislost Check the video posted above!


AirLift_Lucas CharlesChris15 I've got some short clips from my phone, but check the video that Steven posted up above :)


Steve Hayward Agree, love the fitment on the cage.


LopingCamshaft that one is pretty sick, but this one remains my all time fav https://www.youtube.com/watch?v=KWxCv13njCQ




jglucker Jesus. That's nuts. Not an I-6 purist though? That engine with the OS Giken head is worth like $100k and has a 10k redline.


Wow. It's a Z without flares, Watanabe's and it's also got it's rear bumper. Amazed I am. Nice!


StevenFallas farrrrrkkkkk what a fabulous bark


awesome! these photos are right around my backyard


Wow this thing is perfect. I love the simplistic exterior.


LopingCamshaft damn 100k?!


Here is a great video (no wind noise) from the shop's website with some crazy revving and roll-on acceleration...this thing is gonzo!  





Honestly speaking..i never liked the 240Z until this one..and that says a lot on my part


I would not drive this thing too much for fear of getting hit. This thing is amazing and beautiful. Great job on the build and I tip my hat to you sir.


~280rwkw for an N/A 3.3ltr 6cyl... wow!
Also, the mechanical appearance but actually electric windows is genius haha *thumbs up*


My god that's beautiful.


need a video of this thing. i wanna hear it scream.


What a beauty! I am jealous >:


Those headers are a thing of beauty


can nissan go back to these years of the z, and just rethink the 350 and 370 (mad respect for those two cars) and make a new z with the engineering of a datsun z, and the body of a 370, but less aero looking. Anyone else think that would be perfect.




This thing is fkn cool man.


Yeah buddy!
Makes you wonder who'd win in a race:  FUGUZ or this?


It's like the Blackbird and Devil Z all in one. Sweet.

Gianluca FairladyZ

i'm so happy they didn't touch the body with that overfender mainstream..........  stay classy!


im in love..............

Closed course films

This is the motor the fuguz should have had. Zero excuse. Fuck outa here with that rb shit.
Beautiful motor z garage put together. NorCal muthafuckers


So.. Awesome article, come back acouple of itmes already to read it again!
I need to hear the exhaust note of this car though.. would love a clip ;) ;)


Pure beauty!


davidfryklind the way it revs is hilarious...thanks for this video!


If/When i have more money than sense, i want this car...and/or one from Star Road...amazing Z


How about we add the Green Hornet Z to make it more Fun! That would be a heck of a showdown.


DRiFTaddict So you want a 370z (but less aero), with 1970's technology? the fuq you talking about...


Closed course films that would have been an abomination to the engine... Glad this engine made it into a proper z.


StevenFallas o__0 holy wao!


Car of the month, easy.


Aside from that awesome engine, these guys have to be applauded for preserving the character of the original Z. So many "tuned" cars have gawdy tack-ons and spoilers and decals and look-at-me crap that detract from the car. For all the modifications, this is tasteful and restrained - until you punch it. Then it's Jekyll and Hyde time, baby!


Great idea I'm sure the boys from Z Car Garage will be down!


that car is perfect! Sounds great and is very powerful...



what is your rationale for the cylinder head price being "confoundingly stupid"?

Have you looked at vintage Ferrari cylinder head prices?


Are you high? A 70s look with modern tech would make sense...but what you said is nonsense.


Fuckin siiiiiick. Stunning car.
...only thing I would change is either go with a narrower wheel/tire combo, or increase the track width by a couple inches and go with either period correct fender flares, or a really subtle wide body to maintain the factory look. As is, from the rear, the width of the wheels and the relatively narrow gap between them gives the car a sort of Hot Wheels look.


The number of specific cars that make my heart ache can be counted on one hand ..... this is one of those.


@vonmoldy tbh since you can design a head today, and cast it with a 3d printed sand mould, without the related costs they had in the past ... yeah 30k is stupid.


@SW1 in the past, a low volume cylinder head, was extremely expensive for a reason. you had to invest tons of money in the required dies to make the sand moulds. those dies are extremely complex and expensive, and spreading that cost in a little run made the heads very very expensive. especially during the development phase, you spend a lot in stuff that doesnt work and you those costs add up.

today, you can have designs made in CAD, that have a easier design since you dont need to make dies for the sand moulds. you can just print them. the process is not cheap, and the machine required is not cheap either. but compared to the expense of making it the old way, its dirt cheap.

so now ... a 30k head is stupid, it wasnt 10-20 years ago.


Wowsers.. that is amazing!



Closed course films

I can't argue with your logic..... But I was deeply disappointed when the funds were available the fuguz went with a common swap. Instead really doing art like this build here.
Yes this is proper. I agree


the perfect Z.  that is all that you'd ever need, in one car.


FormulaOneWorld Beautifull


FormulaOneWorld RE71R's...U0001f495U0001f495


Love it




Awesome car. Good to see meaty tyres on it as well.


I am in love, just in time for Valentine's.

If only these heads were a little more accessible, because the entire setup is dream build material, and the cleanest example of an S30 I've ever seen. I still can't get over the power window mechanism, so cheeky and clever.

A roadtrip to Z Car Garage is a must on the bucket list.


aps991323. What an awesome car! If I would ever win the lotto, I would try to buy this or replicate it. Awesome!


Sounds like an old F1 car. That's just ridiculous and I love how little is done to the car as far as looks goes. Such a elegant looking car as it is.


@datsunguy This and the other type of tuned cars you mentioned are two very different ways of approach to similar platform, they require different viewpoints from viewers, and when done right, they're both beautiful. 
Try to have an open mind will certainly make your car life much more colorful.


Closed course films What's so bad with the RB? In my opinion, nothing is more worse than hating something just because it's "too common", to be different just for the sake of being different? may be that's the way their dream car is? So do the owner of this Z, everyone's dream car is their way of the "proper car".

What will you feel if someone comes in here and say "ugly Z with an overprice motor"? or Insulting your dream car?


DNAofMotorsport 240Z!!


DNAofMotorsport my neighbor had a silver one in the early 70's. Neat car!


davidfryklind First time listening to the OS Giken symphony... I can't find words to describe it *---------*


fantastic 240Z! I have its milder blu twin


Factoring in 15% drivetrain loss, thats around 430hp at the crank... from a 3.3L!? Is that figure correct? From essentially an engine block design from the 70s and a modern head?


the car was very good 
really really like to see the car that shiny new car fits like made ​​for walking trailsthe car was very good http://utamadomino.com/app/img/peraturan.html" rel="dofollow" target="_blank">http://utamadomino.com/app/img/peraturan.html and very fast http://utamadomino.com/app/img/jadwal.html" rel="dofollow" target="_blank">http://utamadomino.com/app/img/jadwal.html mix of colors http://utamadomino.com/app/img/promo.html" rel="dofollow" target="_blank">http://utamadomino.com/app/img/promo.html from which to http://utamadomino.com/app/img/panduan.html" rel="dofollow" target="_blank">http://utamadomino.com/app/img/panduan.html make want pobud http://utamadomino.com/ see hatnya http://dokterpoker.org/app/img/peraturan.html" rel="dofollow" target="_blank">http://dokterpoker.org/app/img/peraturan.html kecepatanya http://dokterpoker.org/app/img/jadwal.html" rel="dofollow" target="_blank">http://dokterpoker.org/app/img/jadwal.html was very nice ,http://dokterpoker.org/app/img/promo.html" rel="dofollow" target="_blank">http://dokterpoker.org/app/img/promo.html  suitable for a "http://dokterpoker.org/app/img/panduan.html" rel="dofollow" target="_blank">http://dokterpoker.org/app/img/panduan.html sharp bend http://dokterpoker.org or not sharp I guess motorists http://633cash.com/Games like this is http://633cash.com/Pengaturan" very skilled in the speed I hope I can membilinya someday will whether http://633cash.com/Daftar http://633cash.com/Promo there are http://633cash.com/Berita new cars http://633cash.com/Livescore are better I http://raksasapoker.com/app/img/peraturan.html" rel="dofollow" target="_blank">http://raksasapoker.com/app/img/peraturan.html 'll wait for it , with a stylish car classic http://raksasapoker.com/app/img/jadwal.html" rel="dofollow" target="_blank">http://raksasapoker.com/app/img/jadwal.html style I http://raksasapoker.com/app/img/promo.html" rel="dofollow" target="_blank">http://raksasapoker.com/app/img/promo.html also like http://raksasapoker.com/app/img/panduan.html" rel="dofollow" target="_blank">http://raksasapoker.com/app/img/panduan.html to see would be http://raksasapoker.com/ whether there is a http://yakuza4d.com/peraturan" rel="dofollow" target="_blank">http://yakuza4d.com/peraturan car that is http://yakuza4d.com as fast and forius http://yakuza4d.com/home like in the "http://yakuza4d.com/daftar movie , the car very http://yakuza4d.com/cara_main good car http://yakuza4d.com/hasil designed a way apparently hopefully http://yakuza4d.com/buku_mimpi there will be new cars more good and the price is quite pantastis then chances are I can membilinya the same as you have at this time