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Project THESEUS: A '74 260z

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12 hours ago, Noll said:



Ok, good to know! I did some research, and found an old thread that references the smaller bearing to be good till 250-300hp, and larger one till 400. Would you say that's reasonably accurate? This car may at most see 200 with the L series, eventually.


The 56mm is considered good enough for the non turbo 280zx, what ever the power rating was on it. The 62mm bearing is much stronger and used on the non turbo 300zx but the 71C was more than just a larger counter bearing. I've also heard that when the T5s blow up in the turbo 300zx they can be replaced with the non turbo 71C 5 speeds very successfully.


A new 56mm (made in Japan) should be fine for anything up to a non turbo L28.



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Good to know, thanks! I think I'll go with the 56mm bearing initially, can always decide to go bigger later. This way I can grind the clearance needed at home and not have to pay someone to machine the bearing hole.




Decided it was about time to get the rear floor back into shape.

Cleaned out all the car parts and dust, and had this as a starting point:


Wire wheel, rust converter, paint, primer, and some brake-cleaner later and we have this. Also chiselled off the remaining sound deadening.


Got the spare tire well all painted up. It'll need one patch cue to a tiny amount of rust, but that's simple. You can see that I still need to finish cleaning the trunk floor; there is undercoating sprayed inside for some reason.


New frame rail and taillight surround mocked up.



The bumper mount on the replacement needs some work, I'm thinking I'll graft in this good-condition spare I have:


Unfortunately there's a gap between the replacement and original frame rail due to where the person who removed the section from the car cut it. Still, won't be too hard to make. Debating between butt-welding part in the gap, or making something to overlap the outside and then seam-sealing it well.


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Finished up the front grille that I had disassembled over a year ago and sandblasted. I had got some M3 threaded rod to replace the busted long bolts that hold it all together, but hadn't finished it all up until now.

Opted for bedliner after painting it all, as some of the slats were a bit pitted. It's not perfect, but I'm pretty happy with it. I'll try to get a better pic soon.


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Made some good progress on the rear today.

needed to fix this:


so I made this:



Welded in, seam sealer'd and painted:


Next up, bumper mount. Decided that transferring the one off the other cutoff would be a pain, so I welded up the holes after I ground out all the rust.


Patch was a bit of a pain due to not being able to cut the area out square (the overhang of the panel meant it was hard to get the cutoff wheel in there), but I managed.



Made the overlap brace thingy for the frame rail:


And started to weld it in. It was getting later at this point, and I make mistakes when I'm tired, so I decided to wrap things up here and get back to it on saturday. WIll weld up the rest of this inside and out, then seam seal everything both sides before the floor section is welded on top.



Looking good! Rear is just tacked, and I need to trim off the excess from the bottom of the 1st patch I put in.



I did mess up and weld the rail on about 1-2mm too far to the rear, unfortunately. Trying to decide if I want to drill out the welds and move it back, cut it around the middle somewhere, narrow 1mm and re-weld, or just leave it as-is as that entire rear panel is a bit bent from an old accident anyway. Thoughts?


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Turned my attention to the rear doorjamb corner, which I've been neglecting for a while. This turned out easier than I'd expected, which is always nice.

I started by cutting off the relevant section from my replacement quarter, and spent a good amount of time hammering it back into shape, as it was rather bent. Cleaned up and made a replacement section.


welded in:


Mocked up to make sure I got the curve right:


The section on the car to replace:


Ready to weld:


and in:


And ground down. Pretty happy with the result. I then seam-sealed/primered/painted the backside.


I then turned my efforts to getting the rear frame rail in for good, after I got the fitment at the rear nice. Welded up the overlap brace. A little ugly, but will be hidden so whatever. Welded around the outside too, but no pics.


Welded in at the rear:


Sealed and painted:



The overlap brace is a little ugly, but It'll never be seen, and a bit of undercoating should smooth things out nicely.


Next up, the floor panel and patch of the inner wheel arch, then I can move on to welding in the taillight surround and will be nrealy ready to mock up the new quarter panel!


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Mocked up the rear valence cutoff I have to ensure that the work I did was actually the correct angle etc. I'm happy to report that everything lines up properly, including the top/bottom flanges that are hidden behind the piece.


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Just snagged a set of mint-condition quarter windows pretty inexpensively. Should be here early next week, and then they get to sit in the basement for a few months before finally going on the car lol.

Saves me a ton of work trying to strip/clean out all of the paint and scratches from my window trim, which is nice. Should be able to just bolt them on and go.


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Got the new quarter on today! Still many things to do before It can be welded for good, but this is still an awesome milestone.




Mocked up with my subaru's winter wheels as they're closer to the final tire diameter. Some lowering will still be needed


Made up the patch for the inner quarter, and welded in.


And mostly ground down. A little more to do before it's perfect.


Made the new floor section, and mocked up. Still some tweaking to do, that gap at the back won't be there obviously. Going to do final cuts/drilling then weld this all in on Saturday.


Pretty happy with how the corner turned out:


Once the floor is in, I need to put the section of rear upper rail in (that the quarter sits on), and the other half of the inner arch. Once that's done it's on to a little repair work on the quarter, then it can get welded on!

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15 hours ago, BrothersGarage said:

You've done such an amazing amount of work on this car - quite literally saving it from rusting to death. Major props dude!


Thanks man! Not all of my repairs have been perfect, but will be solid and ensure this car gets a new lease on life for some time to come. This thing would have been a parts-car at best otherwise, and while it's not a series-one or anything, it's still been great to rescue it from the terrible work of previous owners.




Had time today, so did the final cuts, and tacked the new floor section in. Plug welded the whole way along the length of the frame rails as well.


All welded in. This only took about an hour, which surprised me. Not too much warping, and the car was already hit in this corner at some point, so I'm fine with it.


Seam sealed, primed, and painted both sides. Really happy with how it all turned out, and it's awesome to have a complete trunk floor again.


With quarter on:


Also found some paint at a local Walmart that I didn't think existed in Canada. Rustoleum Metallic blue. I'm definitely leaning towards this as a colour now; the blue of the jdm legends 240z has always been awesome, and this should be pretty similar in shade if I use black primer underneath. My plan is for a budget paintjob that still looks good - epoxy primer, spraycan paint, and then 2k clear in a can to ensure longevity. Should look decent while ensuring I don't have to mind when I get rock chips etc.

Just sprayed on an unfinished fender to see the colour:


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  • 2 weeks later...

One of the last big things before the quarter goes on was to get the inner wheel arch reconstructed, so I did that today.

Cut/tacked section from my stash of replacement bits:


And welded in fully:



Sealed and painted:


Same thing for the quarter itself:


It's so nice to finally not see massive amounts of daylight through here. Still deciding on side marker/antenna hole deletes.


Happily, the flange on the lip is perfectly lined up. I still need to remake a section of the flange at the front (it rusted out), but I'm using a repair panel for the dogleg there too, so will do those both at the same time, after the quarter is welded on for good.


The flange at the top by the door was pretty ragged, so I used some copper bar to weld it up. No point making a tiny patch.


Not perfect, but it can be welded to properly now (for quarter install), and will not really be visible after that.


Cut a section from my selection of bits remaining from the 280z shell, and replaced the rusted-out section of my replacement quarter.


Not as seamless as I would have liked, but nothing a tiny bit of filler won't sort after epoxy primer is down:


This will be the last piece of the puzzle so I can finally weld the quarter on for good. It needs a couple patches, but nothing that major.


Also cleaned and painted (with bedliner for a slightly textured look) the rocker cover. Kind of lipstick on a pig at this point, but I'll get the rest of the engine cleaned up down the line. New valve cover gasket while I had it off, no sense in doing it twice.



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Welded up the antenna hole and the side marker hole:



Tacked the quarter on; it is on for good now! Window mocked up to make sure fitment was right, and it is spot on. it's really starting to look like a car again!




Especially compared to before (although even this pic is after a ton of welding):


I must have welded in the rear quarter patch slightly off, so I had to pie-cut it a little to make the cap with the hatch correct. The gap was fine all the way to that point, so it was no an overall alignment issue.


Much better:


Mocked up the taillight. WIll still need to drill the holes for it in the proper locations, unless I decide to go with 240z taillights and rear valence. Still undecided which route I want to go, but if someone has a 240z rear valence they want to sell, let me know!


And overall. pretty decent:


However there are some small bits I  need to sort out before finishing welding. The right hand side overlap is like this:


While the left is this. Need to figure which bit is out of whack (quarter or underneath brace), and decide what to do. If it's the brace I may just drill the light holes slightly crooked to compensate, as they will then sit in the correct place, and shouldn't affect anything else.


Flange is still a little bent from when it was pried off the old frame, but the gap is overall pretty decent. Some hammering and welding and it'll be good. Plus, the outer hatch seal goes over top there anyway.


Next time I have time to work on it, get the door on to check that gap, tweak the other fitment issues, and weld the rest in for good, then seam sealer it all, and I can move onto the dogleg outer skin repair.

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6 hours ago, Spoona_Jay21 said:

This is looking GREAT! keep up the good work! 


on a side note, If it was me, I would keep the 260/280 Tail lights. I personally prefer them.


Thanks! It's nice to finally have reached the point where it feels like everything is coming together. Still gotta do the other side , but that should be way faster.


Fair enough! i like them both, will be mostly a matter of which taillight panel I can source cheap I supppse. I have already refinished my 260 tails, would be a shame not to use them.

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Very impressive work, I'd instantly shy away from something that was that rusty and had that much body work to do on it. Threads like these certainly makes me appreciate the body condition of my Z more. 

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On 8/27/2019 at 7:13 PM, User26 said:

Very impressive work, I'd instantly shy away from something that was that rusty and had that much body work to do on it. Threads like these certainly makes me appreciate the body condition of my Z more. 


On 8/27/2019 at 2:47 PM, Maschinenbau said:

Again, seriously impressive tinwork here. Like, an overwhelming, intimidating amount of tinwork. I would have given up a few pages ago. Keep it up!



Thanks guys, means a lot! While it has definitely been a ton of work, for the most part I've been able to "just" cut off all the panels/sections affected by rust and bad bodywork, as opposed to having had to make 3 million small patches. Still a lot of work, but overall simpler to replace the whole quarters vs fixing what was left on the old ones.


There's still exceptions to that (firewall, a-pillars, and lots of front-end misc need/needed a myriad of small patches), but oh well haha.


I'm going to get the door back on tomorrow and hopefully get the quarter finished up and seam-seal the underside. Then on to the floor!

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it's still odd to think that I've transformed this entire area from a gaping rusty hole back into a complete car. A little uglier than I'd like, but its the underside of the car so no biggie. I'm going to need to strip off some of the paint to seam-seal the quarter, now that it's butting up against everything. After some undercoating it should all be pretty hidden.


Finished welding everything:



And ground down:



Door on and adjusted so it closes. Gap is still pretty tight by the quarter, but it doesn't hit. Not going to do any more tweaking until I get my replacement doors on, as they probably will fit slightly differently anyway.



Now just the dogleg and floor, and all the metalwork on this side of the car is done!

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Started on the seatbelt-mount area today.

Began by figuring out what I was cutting off the replacement section:


Cut the swaybar mount off the mangled remains of the old one, and cleaned up. Won't weld on until I have everything back in the car so I can mock it up with the swaybar to ensure I don't mess up location.


All cut, cleaned, and mocked up. I still need to do some trimming to make sure everything slides fully in to place, and re-make the right-hand side from where it was hacked up when the person who sent it to me cut it out of their car.


I left as much of the old brace in place as possible, so as to be able to weld as far from the control-arm mount as possible for simplicity's sake. Will plug-weld the panel back on top afterwards.


My plan is to weld everything i can from the top, then get the floor/underfloor rail/seat mounts in, and go from there. In the future I'll drop the rear subframe to clean everything up and swap the rear diff (so long as I can source a 4.11 LSD), and will do the bits that need to be welded from the underside then.

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did a little datsun work this evening.

This rubber pad mount and the frame horn in the surrounding area was pretty sorry-looking and had pinholes, so I decided to repair it.

The starting point:


Made the replacement mount. I'm sure it'll flex a little more than the double-stepped one, but shouldn't matter much. I may weld a little bit in the center to reduce flex.


And the point I got to when I ran out of welding gas. Top/side of the main patch done, and bottom tacked in (it wraps around all 3 sides there).


Before I welded it up I had a look inside; other than the usual surface rust, there doesn't seem much unexpected. Some metal flakes sitting by another area I need to patch, but I'll be cutting that out (then welding back in) at a later date for the repair there. Will also be using an internal frame coating on the whole cavity.

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Finished welding and grinding the front frame horn patch, and seam sealed and painted it. Not the prettiest, but some undercoating will smooth things out once it gets to that point.



Made a new patch for the rear inner wheel arch where it meets the seatbelt mount area - I had done this before, but it was with my old welder (bad penetration) and there was another section I couldn't patch until I removed the rear seatbelt area anyway. Decided to cut it all out and start from scratch.


Welded it in, and also got the fitment finalized on the rear subframe stuff and welded it in too!


I'll need to put the floor skin back on the areas I cut out to gain welding access for the structural members, as well as make some bits for it to meet with the inner wheel arch, as the person who cut this out of their parts-car cut it there by mistake. Now the frame is in the correct location, patching the skin is the easy part.


Stuck the floorpan in to check fitment, there's some stuff I'll need to cut before I can tack it in and start patching the trans tunnel.



I also need to figure out where to weld the seat mounts in; does anyone have a measurement to, say, the firewall from the front mount holes I can use for a reference? I may very well move them back a little as I have pretty long legs, but it would be good to have a starting point.

Side note, I also realized that 240z and 260z seatbelts are different; the bucket that the retractor spool goes in that I just welded on is off a 240z, and my 260z assembly is too wide to fit - looks like they changed to wider belts in the later cars. Anyone want to trade for some 240z assemblies?

Also stripped the rubber off the front bumper and polished it up. Looking pretty clean now imo, I'll probably leave the holes (or possibly use carriage bolts to fill) as they're pretty small.


Oh yeah, and I finally ordered some wheels! 15x8 + 0 RKRs. I'm undecided as to if bronze or gunmetal will be better for the blue car colour I'm aiming for, but they were they only set I could find in Canada (no customs fees, free shipping, and the price was actually pretty excellent), so I went with them. Can always paint later if I want.

Found a used set of 225/50/15 snow tires for cheap that I'll be picking up to use for rollers and fitment/suspension testing; can probably sell them for what I paid when I'm done with them.


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Big milestone today, got the floor in! Lots of transmission-tunnel patches to do still, but pan and frame rail are both welded on for good. Also need to decide how best to do the front curve to the firewall, but shouldn't be too bad.


Welded in one of the multiple patches for the seatbelt area. Will clean it up when it's all welded in.



Floor is pretty solid, I'd say:


And underside. Will clean up the surface rust and get it all painted when I get the car lifted up to do some other stuff.


This also seems like a good time to decide on getting rear frame connectors from bad-dog, but from their pics it looks like it might interfere with my current swaybar. Definitely getting their jack plates, seems like a worthwhile mod.

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Thanks guys!



Got some lugnuts today. Need to get some replacement studs too (half of mine are snapped), then I can get the new wheels on when they arrive.


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