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Episode 50 of my '76 Mazda Cosmo Restoration is packed full of detail and information. Possibly more than any other episode released. Because after all, there's a lot to say about designing and building an Atmel 1284 powered CANbus communicating, stepper motor driving, TFT screen displaying, addressable LED controlling, rotary encoder twiddle accepting, heart of an electronic instrument cluster, circuit. That's what this episode primarily concentrates on with a bit more thrown in the middle. It's heavy on the electronics of course, and the last installment before final assembly of the instrument cluster. You might want to pour yourself a drink, sit back, brace yourself (that's what she said). By the way, I made an obvious mistake in this video. Can you spot it?
I'm editing my *** off for the final cluster episode (in the short term anyway). Honestly, this cluster has been a complete boondoggle and I am glad to wrap it in plastic and place it out of the way for now. It sucks knowing that this project has created a huge amount of future work for me as I have to now program the damn thing. So at best in reality even though it is "done", it is 50% done. Plus any future problems created by the fact it is a one-off prototype.
I'm not doing any more cluster videos until it is programmed and working. So this one will go until it is done.
Episode 51 of my '76 Mazda Cosmo restoration is here! First, let's talk length. That's what she said. I know it's ridiculously long. The title of my sex tape. Thing is, this video contains the entirety of final assembly of the electronic instrument cluster and it was an ordeal. Stuff broke, mistakes were made, more stuff broke, and add a long wait for replacement parts.And then I had the joy of reliving it all while editing this monstrosity. I could have split it into two, but then that would extend the instrument cluster to 6 parts and I just wouldn't have it. So dear viewer, I implore you to have the same experience watching it as I had making it. But here's the thing: it worked out rather well and even though I have months of programming to make this cluster actually do anything more than twiddle the needles, I think it was worth it.
So whats next? My goodness its been so long since you worked on the car i forget where you were at. I think you had most of the engine bay mocked up, the front suspension was semi complete? And you had a set of BMW e90 seats in there.
So whats next? My goodness its been so long since you worked on the car i forget where you were at. I think you had most of the engine bay mocked up, the front suspension was semi complete? And you had a set of BMW e90 seats in there.
All of those rememberings are correct. Next up I have to revisit some previous work that I'm not happy with, and needs to be changed for various reasons. So lots of fabrication.
Originally Posted by Akagis_white_comet
DUDE! A new video from you AND M539 Restorations (an awesome vintage BMW channel) on the same day???
I have yet to watch, but I can already say Christmas Came Early. And that IS what she said..
And I'm assuming Christmas will come again before, well, Christmas.
All of those rememberings are correct. Next up I have to revisit some previous work that I'm not happy with, and needs to be changed for various reasons. So lots of fabrication.
And I'm assuming Christmas will come again before, well, Christmas.
Come again? That's ALWAYS what she said Speaking of fabrication, what do you have in mind for the rear suspension? Since the front was converted in awesome fashion to a 5-lug hybrid Cosmo/RX7 setup which can use regular FC struts/springs, I'm wondering what you have in mind for getting 5-lugs on the rear. There was a question in the New Owner section about doing so on a first gen RX7, as the front end 5-lug swap has already been documented. Stands to reason that a SA22 RX7's suspension would be similar to the CD Cosmo in the rear too. Possibly the HB Luce/929 and Cosmo too.
Sorcerer Edit:
So I did some digging on similar suspension setups and found Mazda DID a solid axle setup with 5-lug hubs on the First Gen MPV (89-99). Pretty much a modified version of the HC Luce/929 4-cylinder rear suspension (6-cylinder/Rotary Luce got independent rear suspension similar to the FC). Only downside to the MPV setup is that the hub centerbore is 67.1mm like the FD and early MPVs (89-92) have drums in the rear (LA0x part number). For Discs, go with later (93-95) MPV axles, brakes, etc (LB4x part numbers). As long as you can get the length correct and have suitable bearings to fit, it should pop right in.
Last edited by Akagis_white_comet; Sep 26, 2021 at 03:01 PM.
Reason: Sorcerer Edit
In any long running project, and no one will debate that this is a long running project, there are always things that one looks back on and reconsiders. And for years, there has been a big one in the engine bay: the intercooler. I was never happy with the angular placement and the almost improvised look of the plumbing. It seemed as though it was an after market kit made to fit a space. It was at odds with the engine bay. It ate at me. And after the instrument cluster I wanted to cut and weld! So I made the decision to seemingly go backwards and redo work already done. It was absolutely the correct decision.
Fantastic stuff man. Re-work is a natural part of the process. It also shows that your skills have improved since the first incarnation. I was up till 3:30am this morning redoing part of the Eunos Cosmo Workshop Manual. Just wasn't happy with using what I made 2 years ago. Had to fix that before I started compiling everything together.
Now you got me wondering how the Power Steering will be addressed, but I guess that'll be revealed in the next part.
Just popping into say I appreciate your commitment to the project and producing content. Great to see you and your projects progress throughout the years.
Come again? That's ALWAYS what she said Speaking of fabrication, what do you have in mind for the rear suspension? Since the front was converted in awesome fashion to a 5-lug hybrid Cosmo/RX7 setup which can use regular FC struts/springs, I'm wondering what you have in mind for getting 5-lugs on the rear. There was a question in the New Owner section about doing so on a first gen RX7, as the front end 5-lug swap has already been documented. Stands to reason that a SA22 RX7's suspension would be similar to the CD Cosmo in the rear too. Possibly the HB Luce/929 and Cosmo too.
I had thoughts about swapping an FD subframe however that would require cutting most of the rear structure of the car out. From the factory, the RX-5 is a 4 link setup with aluminium upper arms. Wildly different than anything else Mazda did in the era. For the purpose of the car, I think it will do the job just fine. Will definitely have the rear hubs re-drilled for 5 lug. And will be ditching the crazy stock rear disks (with integrated drum for parking brake) for a more standard design that can make use of a caliper with integrated parking brake (FC, FD, many choices and easy to make a bracket).
Originally Posted by Akagis_white_comet
Fantastic stuff man. Re-work is a natural part of the process. It also shows that your skills have improved since the first incarnation. I was up till 3:30am this morning redoing part of the Eunos Cosmo Workshop Manual. Just wasn't happy with using what I made 2 years ago. Had to fix that before I started compiling everything together.
Now you got me wondering how the Power Steering will be addressed, but I guess that'll be revealed in the next part.
I've just always been unhappy with the original plumbing and location of the intercooler. In fact I can't even remember why I thought it was acceptable at the time. Something about it needing to fit around the power steering pump. Now however, there are plenty of self contained compact electric power steering pumps and truth be told, after moving the car around the shop, the Miata rack requires very little boost. It will mean running a larger alternator, which has always been in the plan. High capacity alternators are so common these days.
Originally Posted by The Spyder
Just popping into say I appreciate your commitment to the project and producing content. Great to see you and your projects progress throughout the years.
This is very much appreciated. The time it takes to film and edit is harder and harder to find. Plus the fact the YouTube algorithm is against me as I don't upload 6 times a day like they want. Videos won't end until the project is done.
Well crap, it looks like the data I posted about what I found has vanished into the ether so I'll paraphrase it here.
Look at a 1994 MPV. Solid axle setup like the CD Cosmo, but available with discs in the rear and the desired 5x114.3 pattern you want. Only downside is they use the FD's 67.1mm centerbore vs the 59.6mm FC setup you have in front. Simple solution is a Hubcentric ring in front like FC guys use when going to FD wheels.
Brake discs are J001-26-251B, same as the Eunos Cosmo.
Axle Shaft with hub is LB40-26-111 (Right) and LB40-26-115 (Left)
If the MPV hubs could be transplanted to the Cosmo Axles, or MPV axles modified to fit the Cosmo axle housing it sounds like a simple, relatively cheap solution to get what you want in the back.
Last edited by Akagis_white_comet; Apr 9, 2022 at 10:54 AM.
Reason: axle part number correction
Well crap, it looks like the data I posted about what I found has vanished into the ether so I'll paraphrase it here.
Look at a 1994 MPV. Solid axle setup like the CD Cosmo, but available with discs in the rear and the desired 5x114.3 pattern you want. Only downside is they use the FD's 67.1mm centerbore vs the 59.6mm FC setup you have in front. Simple solution is a Hubcentric ring in front like FC guys use when going to FD wheels.
Brake discs are J001-26-251B, same as the Eunos Cosmo.
Axle Shaft with hub is LB40-26-111 (Right) and LB40-26-115 (Left)
If the MPV hubs could be transplanted to the Cosmo Axles, or MPV axles modified to fit the Cosmo axle housing it sounds like a simple, relatively cheap solution to get what you want in the back.
that is a good suggestion, the 89-98 MPV is basically if Mazda took the Rx2 suspension and copied it at 110%.
In part 53 of my '76 Mazda Cosmo restoration, I finish the rework of the water to air intercooler I started in episode 52. With the ideal position established, all the tubing needed to be changed to match. And if I was doing that, well, I figured I may as well ditch the pedestrian silicone couplers and clamps for something much more awesome. This is another episode filled with cutting, grinding and TIG welding. The final product is exactly how it should have been from the start!
Time to tackle two more aspects of my previous work I am unhappy with. In part 54, I'm re-fabricating the bracket used to adapt the Vintage Air Compac Gen 2 HVAC unit (parts 29-31) and fixing an issue with the front camber I created when I used Mazda 626 ball joints to allow use of FC RX-7 spindles (parts 39 - 40). Years of looking at my poorly designed HVAC brackets weighed heavy on my conscience and I knew I could do better. So too with the front suspension; I had come to the conclusion that there wasn't enough adjustability to allow proper alignment. This episode, I correct both these mistakes to end up with results I find truly satisfying.
Always a joy watching your latest work. Here's a little treat I found when watching Gosei Sentai Dairanger while taking a break from the Japanese FD Wiring Bible. Aired in 1993, it's the series that was adapted to become Season 2 of Mighty Morphin Power Rangers. This is from Episode 29
I'd know those funky quarter windows from anywhere
Hey Aaron, so I was doing a little homework on a RHD FD that a new member asked out and came across this. Pictures are from a Japanese 1976 Cosmo 1800, giving us an idea of what the interior above the window line should look like.
There was apparently an onboard Self-diagnosis system for certain functions like lights, brakes, etc. Pretty rad stuff for being 1976.
The self-diagnosis lights are the same style, fit and finish as on the cluster, so I'm thinking it's original. Did you come across anything like this at any time? Might be pretty cool to replicate the style with modern hardware. Maybe on the Nexteon screen?
Episode 55 begins the project I've wanted to do since even before I bought the Cosmo: air suspension! In this video I modify the rear trailing arm to accept the air springs, create mounts to allow access to the bolts and fittings, then modify the frame rails with new spring perches. Lots of metal work and fabrication to get the rear end bagged. Enjoy!
Welcome back! I still can't fathom how you jumped right into fabbing when everything surrounding the rear suspension has 40+ years of gunk and goo on it. Might not be a bad idea to take a cue from Past Aaron Cake during the Front Suspension Overhaul and clean everything up before going further. Fortunately, I've discovered the last word in de-gunking damn near anything on a car. In the Workshop Manual for the Eunos Cosmo, it says that steam is one of the preferred methods for cleaning aluminum parts. So I gave it a go with a $40 one on ebay and the worst possible conditions...a BMW
It works. Remember all of the filth, gunk and *insert noun and adjective here* from the front subframe? It sliced right through all of the filth under the hood of my E38. And for the THICK greasy buildup, spritz the area with Dawn Powerwash first.
It also works miracles on brake dust and the earthly bukkake better known as pine tree sap. And from what I've read, undercoating melts off just as well too. Just think of all the money you'll save compared to hiring that fabled intern, the one that was desperate for attention and approval
Hey Aaron, so I was doing a little homework on a RHD FD that a new member asked out and came across this. Pictures are from a Japanese 1976 Cosmo 1800, giving us an idea of what the interior above the window line should look like.
Here's the car in question: https://www.duncanimports.com/used/M...86d2404416.htm
There was apparently an onboard Self-diagnosis system for certain functions like lights, brakes, etc. Pretty rad stuff for being 1976.
The self-diagnosis lights are the same style, fit and finish as on the cluster, so I'm thinking it's original. Did you come across anything like this at any time? Might be pretty cool to replicate the style with modern hardware. Maybe on the Nexteon screen?
That's actually as very valuable resource as I haven't been able to find detailed pictures of certain parts of the interior. Ah ha, so that's what that weird trim is...rear seat bottoms. Sadly that car seems to have the wrong engine.
I really like the overhead console with the diagnostic lights. It almost has an LCARS type feel and is right at home in the 80s. I kind of like the idea of recreating the entire thing in the same spot with an LCD screen. I had already decided to implement TPMS and of course signals to the ECU will be available for the status of every door and window. For the life of me I can't imagine how they monitored the rear brake linings. Perhaps just a mile counter.
Some of those functions will definitely be on the Nextion screen.
Originally Posted by Akagis_white_comet
Welcome back! I still can't fathom how you jumped right into fabbing when everything surrounding the rear suspension has 40+ years of gunk and goo on it. Might not be a bad idea to take a cue from Past Aaron Cake during the Front Suspension Overhaul and clean everything up before going further. Fortunately, I've discovered the last word in de-gunking damn near anything on a car. In the Workshop Manual for the Eunos Cosmo, it says that steam is one of the preferred methods for cleaning aluminum parts. So I gave it a go with a $40 one on ebay and the worst possible conditions...a BMW
I didn't think I would be working underneath the car very much for this so didn't bother cleaning it up. Certainly that will be a priority when I pull the axle and thus have much better access. I've always found that good old kerosene takes the undercoating off very quickly, then another blast of brake cleaner to remove the kerosene.
the earthly bukkake better known as pine tree sap.
Part 51: Electronic Instrument Cluster Conversion - Part 5
