20B 5spd '90 in Okinawa!

I've got a pretty simple Nikon D3000, nothing super fancy but it does great for the most par. The Mazda employees were really upbeat and friendly, we also got a quick walk through of the assembly line and they were pumping out CX-3's, CX-5's and new Miata's like crazy. It was really cool to see that in person as I'm planning to buy a CX-5 sometime mid next year.

The SpeedHunter's guy came out to Okinawa and did a a few articles and various cars and stuff. He did shoot a bunch of pictures of mine, but I guess nothing really came of it unfortunately which is a bummer, I would've like to see all the other pictures!
Changed all the fluids earlier this month to include DOT 4 brake fluid. Found out that the Cosmo doesn't bleed brakes like most cars such as having another helper pump and hold the brakes, instead there's an accumulator next the brake master cylinder. All that has to be done is turn on ACC power, give the car a few seconds, then have the helper step on the brakes hold it down once, and then I break open the bleeder valve and the accumulator will continuously pump out brake fluid until I close the bleeder again. Talk about convenient! Plus the DOT 4 fluid seems to have made my initial bite a bit higher in the pedal travel. Either that or getting fresh fluid in there.

Kitty photo bomb!


While I was under the car, I just happened to catch a flash of purple from the side my eye and upon further inspection, I have an Exedy clutch! Never knew it lol.


With the cooler weather out here I decided to give the Cosmo a go at autocross. My current helmet was kind of stinky, and wasn't very comfortable so after a couple hours surfing UpGarage, I scored this nice Arai for a steal. Not too long after, I slapped a mirror'd gold shield on.




Unfortunately, no action pics of the Cosmo as I wasn't taking any pictures, but there were some guys there that got pictures of it stationary I guess :lol:





So about the actual driving. The course was very small, I was never able to make it out of 2nd gear. The car did great reliability wise, but it definitely showed me it needs some more upgrading, granted this type of driving is out of the norm for it.

Main issue I was having was putting down power. The VLSD is straight garbage, to the point I was questioning if it really had an open diff instead. There were 2 very sharp a slow turns that I had be extremely light on the throttle as too much gas would cause the inside wheel, and the inside wheel only to spin. IT WAS SO ANNOYING. I tried stiffening the rear dampers to hopefully kill some body roll, but it didn't help much. Otherwise the car did great with braking and powering out of the faster turns.

It didn't take long for me to realize this car needs a proper LSD. Luckily I found a Mazdaspeed 2 way here on island for a good price. I really wanted a 1.5 way, but the 2 way was just too convenient to pass up. I've ordered a separate pumpkin from Yahoo Auctions just in case this LSD acts like most harsh 2 ways,. If it does, I'll throw the stock back in and order a 1.5 way. Also, the word on the street is that'll I'll have to switch to using 13B Cosmo output shafts, so also waiting on those to come in also.


A couple days after the event, the GReddy Profec I ordered came in. I bought this to cure the low boost problem I was having. I was only seeing about 5.9 psi, but it was a rock solid 5.9, and I couldn't find any obvious broken hoses or the such.


So I got to working on removing the intake, but hose on the secondary was hard stuck. Managed to twist it off, only to hear it split in 4 pieces! Luckily nothing fell in the turbo's, but I supposed 25 years of heat will do this!


Decided to order a new one from Mazda after coming up empty on the used parts market. Apparently I bought the very LAST intake pipe Mazda has on shelves. Lucky me right?


A week later, the intake pipe showed up, and I got the Profec slapped in and everything back together. Got boost lo set to 8psi, and boost hi set to 12psi. Still working on the settings as the Profec is super finnicky and infinitely adjustable. I'm also trying to tune out the pressure drop in the higher RPM's. It pulls hard after the transition, and slowly drops above 5500rpms. I think the engine is just telling me it wants a single turbo lol. Sorry for the crap iPhone picture.


Found another great deal on a copper Koyo that I couldn't pass up. Been waiting for a used aluminum one to show up, as they're CRAZY expensive brand new. I think this Koyo should do fine for now. Also installed the Samco hoses I had laying around.



That's it for this round. Like I mentioned earlier, waiting for the other pumpkin and out shafts so I can get the 2 way installed. I'm pretty excited for that.
Alright, new update.

Finally got the boost controller dialed in. Aimed for 12 psi on high boost and it usually maxes out consistently between 11.6-12.0 psi. It pulls like a freight train, that 3rd rotor torque is amazing!

Also, I got a bit tired of the Defi bluetooth set up. It worked great, but a couple of things were annoying me. First being was that my phone was sometimes bluetooth stupid, and I'd have to turn the bluetooth on and off to get the phone to connect to the Defi box. The box and the app worked FLAWLESSLY, but my phone was letting me down. That, plus it was getting to be annoying having to back out of the app to change music, because I'd have to reconnect to the box when backing out.

So one day, my friend mentioned how he just installed his Defi Advance ZD, and I was like WTF man I've been trying to sell mine for months. Then it hit me, why am I not using my BNIB ZD?! Initially I had wrote it off because it didn't read boost, but the GReddy Profec reads boost big as day. So with a little messing around, the ZD is installed!




I actually prefer this set up as everything is centralized, and no screwing around with my my phone. The ZD blocks the speedo and tach a bit, but the important parts are visible.

Then the big news, I finally got my under body braces back from Australia! These things are seriously rare, like Yeti fist fighting Big Foot rare. So when I bought them around last July, I had them sent straight a good friend of mine, and fellow Cosmo owner who had connections that could get the braces scanned and reproduced.


Took some time, but got them installed! I really want my own lift.


That's it for this time. The other big news is that I found out I actually needed a pumpkin and axles from a 13B Cosmo to install my Mazdaspeed LSD. After a month or so of coming up empty trying to find a junked 13B Cossie, I finally found one locally that another Cosmo guy bought to cannibalize. So score! I should have the LSD installed by the end of the month!
Time for another periodic update.

Big news, I FINALLY know where the military is taking me next....back to my first base in Tucson, Arizona!

I'm both bummed and excited about it. I really wanted to stay overseas, like I would have sold my left nut bad, but on the flip side I still have lots a good friends in Arizona. Plus between Cali, Arizona, New Mexico, and Nevada, I'm spoiled for choice on tracks. Can't complain about that.

So since I knew where I was finally going, I got to searching for a daily for myself. Stumbled across this great looking FB on craigslist. Turned out to be very close to a friend of mine and I had him check it out. Long story short, it's now mine! '85 GSL-SE which looked to be in good shape for it's age and mileage.


I wasted no time buying parts for this thing. Currently I have a set of 16x7 +25 16X8 +25 Watanabe's ordered and on the way to the car. Along with a Koyo radiator, Racing Beat silicone hoses, and Project Kics R40 lug nuts to compliment the Wat's.

Back to the Cosmo.

I finally snatched the 13B diff out of the junked Cosmo that was being parted, and had a local shop install the LSD for me. Pictured here is the 13B diff on the left, 20B on the right.


On the outside, they're identical, but on the inside is where things chang. The output shafts on the 13B are smaller than the 20B's, allowing me to use a Mazdaspeed 2-way made to fit a FC or FD's diff. The gearing is also shorter, giving a small bump in acceleration versus the longer ratio on the 20B diff.

I haven't properly driven the car hard with the diff in yet, but fooling around a few times trying to get used to it, it feels great ofcourse having a true LSD over the "meh, I'll lock when I feel like it" VLSD that was taken out. Also the Mazdaspeed 2-ways seemed to have a reputation of being more street friendly and less chatty than say a Kaaz or Cusco, and so far I can reconfirm those statements. I added some of Amsoil's Slip Lock Gear Additive, which is designed to quit down chatter, and so far it works like a charm.

Also managed to find a good deal on spark plug wires to rid of myself of the tired and ugly stocks ones.



I know I've got some severe color clashing going on, but I will eventually redo the grounding cables in a more neutral color, and change my radiator hoses, as I originally ordered them in black!

With my impending departure from Japan, I decided I needed to pick up the pace on converting my interior to black as I know shipping would absolutely destroy on me on some of the bigger items.



So far, I've gotten the center console and entire rear seat set delivered, along with a few odds and ends that I'm waiting to install when the dash shows up. I've got the center console and back seat in, I'm just waiting on door cards and the dash to be delivered.

Hard to tell form this picture, but the rear seats compliments the Recaro's a million times better. The beige interior was very gentleman like, but this black leather is so classy! Unfortunately it's damn hard finding black carpet and black headliner and such for this things. So looks like i'll be rocking a super sweet black and beige interior for a bit, cold be worse!


Lastly, went to a get together tonight which is usually the huge end of the month meet, but the weather was garbage. A group of us round eyes got met up in an arcade parking garage. Here's a video one of the GT-R guys took of the meet, I'm in there a few times. Enjoy!



Man, I don't even know where to start...I'm super jealous of all your updates! Props to you for doing so much with your Cosmo, so you're taking it back to the States with you then..?

Also, congrats on that super clean FB! It would be very cool to see a thread here on that beauty too! (2thumbs)

WARNING! Impending question barrage... :p

Interesting upgrade with the diff...Are you concerned at all about using the smaller 13B shafts with the 20B? Any idea how durable the stock 20B diff is..? Can it take a lot of power?

Your interior is looking great (I really dig that steering wheel), are you still planning on custom touches for it like Alcantara?

What are your plans for the Cosmo once it's Stateside (if I'm assuming correctly)? Do you still want to go with a custom titanium exhaust?

Love all the pics but this one straight up scares me!


I'm still using a lot of stock rubber and I fear that mine are in or close to that state. I do plan on replacing it over time though but with silicone tubing and titanium pipe (if I can swing it).

What's the status on your bracing that was scanned in Oz, who's going to offer it? Also, how does the Cosmo feel with it, is it worth it? I did speak to Kawato-San a bit about bracing and he said it depends on the type of tires I want to run etc...That a certain amount of flex is a good thing for a street car (at least)...He was mainly referring to reinforcing / cross-bracing the rear strut towers though...Now that I have coilovers, I love how the Cosmo handles and I wouldn't mind making it even more confidence inspiring and enjoyable to drive...I'm wondering if braces like these would help in that department.

Well I think those are all the questions I have for now...Thanks again for sharing everything that's going on with your Cosmo man, much appreciated! :D

Ps...Any video from the AutoX session?
Regarding the 13B diff, the 20B axles bolt right up to the 13B's output shafts on the diff. The only weak point I'm concerned with are the 25 year old something axles enduring the locking of the 2-way and the 20B's torque. So far so good though, as I have a decent amount of experience daily-ing a 2 way LSD, and as predicted the Mazdaspeed isn't overly aggressive.

I'm still planning on having the top "ring" of my interior wrapped in either alcantara or micro suede. I'm talking with an interior guide later this month to get a price estimate. I switched to a black dash recently, but I'm still using the old dark brown upper dash because I couldn't find one in black. It looks weird.

The Cosmo is definitely going Stateside. Running into a bit of bump with the military shipping it right now, just waiting on a few more specifics from them, but it's going back hell or high water. Right now the plan for it Stateside is to get the body and paint re-freshened. I actually just bought a wingless trunk from Australia because my winged trunk now is super rusted at the wing's mounting posts. A responsive single turbo and electronic water pump is also on my to do list, but for now the immediate plan is to attend some open tracks days! I'm definitely still wanting to go with a bigger single exhaust too.

Yea I was not too pleased with the intake pipe cracking the way it did! I wanted to go silicone, but I didn't think I could find anything with that complicated of a shape. I'm becoming a familiar face with the local Mazda dealership lol.

There was actually a group buy for the braces recently on the Facebook Cosmo group. If you're interested I can shoot you the info, I'm not sure if they have anymore open spots but at the very least I'm sure they wouldn't mind sharing the CAD and 3D drawings. As far as performance wise, they made a HUGE difference in cornering speed and confidence. Ofcourse it's one of those things you wouldn't normally notice unless you're driving it hard, but the 2 big things I noticed after installing them was that I was able to apply throttle earlier, and more confidently when exiting a corner. Before it was a bit nervous and scary as the rear would try to slide out, and the VLSD was really unpredictable. Which leads to the 2nd biggest thing I noticed, the VLSD actually behaved a lot more properly, and locked up when I wanted it to. The last AutoX event felt much better.

Last AutoX event, which was mostly a 1st gear course because the lot we have to use is tiny and when the VLSD was still in, I was the 8th fastest out of 30 participants. Not bad at all for a "luxury" coupe!!! This car really, really, REALLY shines on the togue and roads where it's mostly 2nd and 3rd gear being used. Right now though, with the combination of the 2 way + the 13B's higher final drive (shorter gearing!), under braces, coilovers, brakes, and RE-11's, the car is kickass in the corners. I can't wait to get it on American road courses.

I have a couple videos from some other guys that were there, but nothing really focusing on the Cosmo too much. I almost bought a GoPro last week, but couldn't commit to the price lol.

Keep the questions coming man! I don't get asked very much, other than my wheels, my car is very incognito. It seems to only draw the attention of middle aged Japanese men, hahaha!

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Well not too much more in the way of changes. I finally got black doors cards and a black dash installed. Big news though is the car is finally on its way to America!