Popcorn: Miata/Datsun PL521 Hybrid Build
 

I was thinking about doing this as an EV, maybe a K24Z3, and then it occurred to me... I have all the parts to do it as a Miata sitting in my garage... in my Miata, Mental. I have driven it less than 250 miles per year for the last 6 years. Keeping it for sentimental reasons (and the kick-ass stereo. Seriously spend more time in it listening to music than I do driving it.) So Mental is going up for sale, and when that fails it will get parted out out to make way for something more, ummm, useful. I need a truck, seeing how I keep borrowing them from other people.

Mental pics:
https://cimg3.ibsrv.net/gimg/www.mia...a45c164752.jpg
https://cimg0.ibsrv.net/gimg/www.mia...6a01b75cb7.jpg
https://cimg2.ibsrv.net/gimg/www.mia...51d2ef041f.jpg
So I bought this the Datsun PL521 pickup and sat on it for a year waiting for inspiration.
https://cimg3.ibsrv.net/gimg/www.mia...d9b1272682.jpg
https://cimg6.ibsrv.net/gimg/www.mia...aa90bc78ce.jpg
https://cimg7.ibsrv.net/gimg/www.mia...1e0ec03cd4.jpg
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https://cimg4.ibsrv.net/gimg/www.mia...76b4cbfb5e.jpg
I bombed the hell out of it and threw out all the interior. It had been sitting in AZ since 1986 and all of the non metal bits have perished. That was how it sat on the lift for the last year.

And then inspiration struck. Dismantling and disposing:
https://cimg6.ibsrv.net/gimg/www.mia...8b651a7d93.jpg
https://cimg8.ibsrv.net/gimg/www.mia...07f1d9ffa9.jpg
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https://cimg5.ibsrv.net/gimg/www.mia...8ae7e7982c.jpg
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Making notes about axle centerlines:
https://cimg4.ibsrv.net/gimg/www.mia...2a9a24da68.jpg
https://cimg8.ibsrv.net/gimg/www.mia...31e7e157eb.jpg
https://cimg6.ibsrv.net/gimg/www.mia...60741ab293.jpg
Frame weight: (ignore the cross, etc I did not pay attention to where I put each scale.)
https://cimg1.ibsrv.net/gimg/www.mia...84d5571957.jpg
https://cimg2.ibsrv.net/gimg/www.mia...56b82985a8.jpg
Total vehicle weight (required for CA truck registration) was 1980 lbs. Crazy light.

Playing around with the frame in Solidworks:
https://cimg5.ibsrv.net/gimg/www.mia...ff59c80e84.png
https://cimg6.ibsrv.net/gimg/www.mia...82134460b3.png
https://cimg8.ibsrv.net/gimg/www.mia...6aa5181e43.png
Cutting off all the OEM suspension mounts:
https://cimg7.ibsrv.net/gimg/www.mia...05016e28d6.jpg
Mocking up the rear subframe. I wanted to push it up as high as possible, but even then it is not going to be as low as Mental is. For reference, Mental is ~4.5" pinch weld and 3" between the frame rails and the ground. The truck will probably end up at 4.5" from the frame to the ground.
https://cimg4.ibsrv.net/gimg/www.mia...bce0417610.jpg
https://cimg7.ibsrv.net/gimg/www.mia...c6d2cd34d6.jpg
https://cimg0.ibsrv.net/gimg/www.mia...3a89863762.png
https://cimg3.ibsrv.net/gimg/www.mia...05286806e6.png
My computer is not happy with those scans for the subframes. Too many triangles for Solidworks. Gets weird when I turn on shaded with edges. Plus those scans are slightly crooked and not watertight. It is going to take too much time to straighten out for FEA, so I will probably skip on that.
And that is where it is now. Going to be much cutting and welding to get it working. I am hoping that I can have it rolling at a fixed ride height before the end of the month, but that may be a bit optimistic.

Interesting. My Datsun PU was a complete dog, and I hated it for that.

Did some more cutting and test fitting.

https://cimg7.ibsrv.net/gimg/www.mia...3455cc0d9e.jpg

https://cimg2.ibsrv.net/gimg/www.mia...be26ffdddd.jpg

On to cutting. Ended up looking like something out of a slasher flick.

https://cimg6.ibsrv.net/gimg/www.mia...cfc0cb3838.jpg

https://cimg8.ibsrv.net/gimg/www.mia...735d8ca2b6.jpg

And then some fitting to see how much more I needed to cut out.

https://cimg1.ibsrv.net/gimg/www.mia...8936575b1a.jpg

https://cimg3.ibsrv.net/gimg/www.mia...7a523bca2c.jpg

https://cimg7.ibsrv.net/gimg/www.mia...8ba21f57b1.jpg

This is still higher than the planned static ride height, so I cut some more out. I may have gone a bit too far... the frame started to feel a bit springy right around the cut areas. So we shifted to welding, which I have never done. But Ed and Eric can and showed me how. I suck at it, so Ed took over and welded until we ran out of gas. I will practice on something before doing any more. Still need to add more structure back into it, but I have some ideas for that.

This is certainly an interesting one, looking forward to seeing where it goes!

Some more cutting and fitting. Close enough on the rear to move onto the front.

Full bump:

https://cimg7.ibsrv.net/gimg/www.mia...207f40f3cd.jpg

Static:

https://cimg0.ibsrv.net/gimg/www.mia...1b15410f67.jpg

Full droop:

https://cimg8.ibsrv.net/gimg/www.mia...3a3f5b5c85.jpg

There is 2" frame to ground clearance at full bump and 4" at static. I am planning on spacing the top hats up about 1" to allow for longer shocks and more stroke.

sick

Not much of an update, but took this:

https://cimg7.ibsrv.net/gimg/www.mia...19bc44e2ed.jpg

To this:

https://cimg4.ibsrv.net/gimg/www.mia...caebdc8e07.jpg

And this:

https://cimg0.ibsrv.net/gimg/www.mia...47e9de44e5.jpg

Cutting out the floorpan was much harder than I had planned on. Poor Monty.

Not much truck action this weekend. I am getting read to sell or part out Mental. I figure there is a street value of right at $20k of parts in it. Don't wanna know how much I have spent on it in the last 10 years.

This project has now gone sideways into a crowd of bystanders...

https://cimg9.ibsrv.net/gimg/www.mia...7249b29621.jpg

Ok, it was hit by a Hyundai, based on the bits and pieces found in the trunk. No innocent bystanders were hurt in the filming of this thread.

I mostly bought it for this:

https://cimg3.ibsrv.net/gimg/www.mia...d90bd906a6.jpg

2.3L, turbo, 310hp/350 ft/lbs with TONS of aftermarket support. Stuff you would never want to put into your car. Amazing what sales numbers can do for a platform.

This is a 2015. I kinda bought it spur of the moment, and maybe should have done a bit more research first. I wanted an auto transmission (easier since I don't have to worry about where the shifter goes) and Sync 3 (gets Android Auto). I got a 6 speed auto and Sync 2... with no Android auto. That is now an $800 upgrade. Boooo. Should have gone for the 2018+ with a 10 speed and Sync 3 included. The prices on Copart did not change much until the 2020 model anyways. If I could only sell this for about what I have in it (i.e. small loss) I would redo it.

FWIW, this is cheaper than doing a K24Z3 swap with a BMW DCT once you add in the cost of getting the K24 up to 300hp and the associated electronics. I will use just about all of the electronics from this in my project. I can't wait to see what the wiring harness weighs.

Anyways, I spent months agonizing over how to do the front subframe install. I had put the subframes so far up into the stock frame that I was looking at having to split the frame to get it to work. I then had the idea of ditching the rear FLCA mounting point from the subframe and recreating it inside the Datsun frame. I am now working on that with a local fabricator, and hopefully we will have it rolling again this month. Then I am going to get Renderos Racing to do the roll cage / chassis stiffening. While it is in his care, I will work on parting out the Mustang. I am really hoping to have a running vehicle this year. Maybe not on the road again, but close.

Edit: I did a burnout in the parking lot. No bystanders to witness this event.

Super cool project... watching with great interest, as I've been scheming about putting NC subframes/suspension under a Mk1 Ford Capri.

I have been surprised to find that some of the NC engine parts bolt onto the EcoBoost. The NC transmissions are a bolt on, as is the oil pan. Makes me want to try an EcoBoost NC swap. The dressed engine weighs in at 300lbs and the 6R80 transmission is 200lbs.

We got the front suspension fitted in. Still needs some adjusting, but the the hard part is done.

https://cimg8.ibsrv.net/gimg/www.mia...2e7ea79ff3.jpg

https://cimg9.ibsrv.net/gimg/www.mia...6085d244d6.jpg

https://cimg2.ibsrv.net/gimg/www.mia...16acc1ad9c.jpg

https://cimg5.ibsrv.net/gimg/www.mia...3f539418c3.jpg

Back to the rear next week and hope to have it rolling again soon. I had to store the bed and body outside and we have had more rain in the last month than this truck has seen since 1986.

amazing. I wish I had this level of skill to do this for my Datsun Z. I'd have loved to use XIDA's

After taking a bunch of measurements, we decided that the subframe install was only off a small amount and that the frame has some twist in it. We think it will be able to align well enough and went ahead and welded everything together. She is not coming apart again.

And then we welded the rear subframe in.

We decided to do the custom rear shock mounts instead of the OEM ones. I need to redraw them slightly before sending them out to be made.

It is going to need custom shocks.... lucky for me I work for a place that specializes in custom shocks. Still going to be $$$ though.

This is starting to add up. I have just hit the amount I parted out Mental for. That Mustang hurt the budget, but I decided that it was worth it for a running and driving vehicle. Sure hope that motor fits between the frame rails and under the hood.

I think you're going to really like that engine. While the 3.5 I have in my truck is larger, I think that Ford got it right with their latest generation of engines. I haven't been this satisfied with the power delivery of a vehicle since my 5.0 Mustang.

Oh, wow. Just stumbled across this build. Epic, and subbd for updates!

Absolutely insane. Subbed for updates.

Rear shock mounts tack welded for fitment check.

Attachment 227048


Attachment 227049


Attachment 227049

Not perfect, but close enough to work.

Everything is welded up. I hope to get it rolling again this week and the body back on next.

https://cimg5.ibsrv.net/gimg/www.mia...a106477b8a.jpg
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It now weighs 262 lbs. It was 173 when I started. That was before cutting out the OEM suspension mounts. I have kept all of the cut off parts and am going to weigh them here in a bit, but I don't see how I have added 90 lbs with the subframe addition. I also have a spare subframe set and will weigh those too.

Front Subframe 36 lbs
Rear Subframe 34 lbs
Metal removed from frame 75 lbs
Top hats 32 lbs (for 2)

Added 102 lbs, removed 75, difference of 27 lbs. Unless we added 63 lbs of welds, I don't know why it is so different.