My Datsun Fairlady Z (Rebuilding a Japanese Classic)

Still tuning the carbs. Runs much better now, but I still have to adjust the floats - there's a bit of hesitations when the idle jets pass the torch over to the main circuits.
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Been a while since I made an update! The 'Samurai' Z is well tuned now - after almost every millimeter of hair was pulled from my head trying to figure out how to tune three Japanese carburetors - but she's finally running well! Here's a quick video of how she rolls :)



I'll take a better one soon.
 
That looks awesome. So clean!!

I love the throttle return spring and mount. :dopey:

Thanks man!

The location and the stiffness of the throttle return spring is still under consideration. Stiffer spring = stiffer pedal and faster retention. I'm gonna be replacing the PCV breather out of the valve cover, too, but I haven't gotten around to it.

This project started almost 4 years ago...it's really satisfying to see it all come together, but also intimidating to think about how much is left to do!
 
I am glad to see you bringing an S30 back to glory. I owned a 1978 280Z years ago that I had to let go.

If my back will ever get healed I am going to start a project car thread myself. I currently have a '93 Mustang LX hatch and some big ideas. Not my first choice of car, but I see potential.
 
I am glad to see you bringing an S30 back to glory. I owned a 1978 280Z years ago that I had to let go.

If my back will ever get healed I am going to start a project car thread myself. I currently have a '93 Mustang LX hatch and some big ideas. Not my first choice of car, but I see potential.

Get on it dude! It's never too late to start a project. What's your plan for the 'stang?

That noise is absolutely amazing. Did you do the crackle finish for the valve cover yourself?

Thanks bud! I'm still tuning the timing/carbs a bit, but once she's running perfectly (I'm a bit of a perfectionist) I'm gonna hook up the Go-Pro and do a proper recording.

The trick of the paint is to get the wrinkle paint and spray it in one direction - let it dry - then paint it again in a different direction. Gives it that nice wrinkle and rough finish. I bought that new oil cap, though :)
 
The Samurai's electrical overhaul is nearing completion! Every wire in the car, from front to back, has been redone, replaced or discarded. The car runs on what is needed. No heater, no fan controls, no radio, no antenna switch - not even the fuel light was spared. The car runs on only what's needed, nothing more and nothing less.

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The car offers a very intense driving experience. The original motor would struggle to lump it's way above 5,000rpm, but this new motor walks over it like it's nothing - all the way past the 8,000rpm mark where my tachometer ends. I guess I need a new tach!

The drivetrain is having a hard time keeping up at higher RPM. Tranny grinds above 7,000rpm if you shift it and the rear end definitely needs some attention. For the time being, the car gets driven with about 50-60% throttle at most before I can get the rest of the car to catch up! My hood is even having trouble closing now and it's because the whole hood got torqued from the engine! Definitely a different animal in there.

Here's a little preview of how she sounds. If you think that's pretty quick, remember that's only about 60% throttle (I don't want my rear-end to fall off on me!) This shoebox of a car would fly once it's ready to be pushed at WOT.


 
Alright, here's the scoop.

The whole wiring process was a success! Got a big box full of stuff that I stripped out and it feels good to shave off the excess weight!
Also got new headlights installed with their own separate wiring to future proof the chassis harness. They're nice and bright!



As some of you may have noticed, I am no longer using Weber carburetors. In fact, I'm not using the other popular choices either - Solex and Mikuni. I am instead using OER Racing carburetors, formerly known as SK Racing. These bad boys were designed specifically for these Japanese motors and felt like the perfect choice for my 'All Japanese' motor. The problem with this sort of rare assembly is the lack of support for them here in the States.

In California, we have a carb shop known as Pierce Manifolds. They possess one of two Weber test benches and make up for pretty much all the Weber work done on this side of the pond. They tune over 95% of the cars that attend the famous Rolex Monterey Motorsports Reunion (over 520 of the 550 cars in attendance this year had their carburetors set up by them) and yet they don't have the parts or the support for the carbs I own. Because of this, I had to experiment a little.

(My visit to Pierce Manifolds)
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The jetting for these OER Racing carbs is different than that of Webers and Mikuni's - but some things are the same. In my experimenting, I learned that I can modify idle seats to use Weber pilot jets. I can also use Mikuni air correctors. But I do, however, have to use OER main jets. This hinders the tuning process because of how expensive it can cost to order bespoke jets from across the ocean. Almost as expensive as the race gas I have to use...

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There's also the problem with how precise everything has to be. This motor is built to operate on the razor's edge. This means the settings need to be exact for it to run properly. This requires lots of different tuning setups and lots and lots of hours and experimenting. These things are by no means cheap!

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As of right now, my pilots are running a tad rich, so I am looking to migrate from a 70F8 to a set of 62.5's. The mains and air correctors need to change drastically, falling from the 220/160 setup to a 160/170 - 135/140 setup. All these new jets are currently en route from Japan, so I'm excited to see how they do!

I'll keep you guys updated on when they arrive. Cheers!
 
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From what I've heard, OER is a combination of everything (Solex/Mikuni, Weber, Dellorto) but it's hard to find any info besides Japanese that You probably know more of. Best of luck, I love to see OER anywhere from the moment I found about them. My favorite carbs after FCR!
 
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