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I've used a ton of used parts in motors over the years, after all, the new parts are only new until you turn the key that first time! A little something for all you guys recycling parts, this outfit claims to be able to make parts bigger: https://www.motortrend.com/how-to/1511-save-some-money-by-coating-your-pistons-with-abradable-powder-coatings/ Since the motor I'm working on has three good bores and the fourth is about .004" big, I could have honed that fourth bore straight and had one or more pistons coated rather than all new pistons and boring the block.

Who is this now? Contact info or a link would be a help. Are you referring to www.rebelloracing.com ? It's pretty amusing to have a motor where shipping it UPS for machine-work might not be cost-prohibitive.

Plasti-gauge won't tell me if the bores aren't in-line, but hearing nobody worries about it and knowing the block is short and fairly stiff, I guess I won't fret over it. The manual does say the main caps should be installed and torqued before boring the cylinders, so that seems like a thing to do. I'd really like to have a head or pretend-head on there to pre-distort the block, but unless someone knows someone with one, I might not take the time to make one for just a couple engines. Interesting the point about measuring tools, in measuring the valve-stems I first tried calipers (guessing sticks) and wasn't happy with the results, next broke out a well-used Starret micrometer, didn't like those results, calibrated it against a gauge-block of a nearby dimension (.3), still wasn't happy, so made up a stack of gauge-blocks and used those to really and finally have numbers I couldn't doubt. At issue is the fact there is .0006" between max and min, and that I'd expect the unworn part of the valve stem to be somewhere between the min and max values, but the genuine Nissan valves have stems that are at most .0002" over the min values in the service manual and some are actually below the minimum value in the manual at every part of the stem! Interestingly, a third-party valve out of another head is well withing spec. Just weird.

On straight-sixes and some V-8s, it's a common longevity-thing to trim the main-caps and ream them uniform and in a line. Was the Japanese machining good enough and the A-series block short-enough that this is a waste, or is there some value in it?

Time for new batteries for sure, the 200 ah plastic case lipofe4 aren't the very-highest energy density but are really easy to integrate and not so critical in terms of BMS requirements.

There's a 1200 sub forum where this is more likely to get seen by the right people. Might be good if the moderator moved it.

They have some really good prices on the sheetmetal, compared to what I'd expect at least. Shipping is tough. I bought one of those hoods from Greece and it arrived badly damaged, surprisingly they did have me send it back and then sent me another which arrived fine. Considering the shipping cost, it seemed really weird to send the bad on back, but whatever. There was one folded seam that needed a touch-up along where it met the cowl, but otherwise the fit was just fine. I do have the old hood and a fender, both salvageable and apparently factory, but not worth my time to get just-so.

Any preferred piston brands for a simple street motor guys, or thoughts about if it's worth boring from the bottom or is the 5-mains block so rigid I shouldn't care?

There's a difference between confidence in my work and things happening. This engine was built by the factory and yet needs an overbore. Was it rough service, neglect, or just an unfortunate incident. oil pan gets holed and the debris also takes out the oil pressure light... remote possibility, sure, but I'm old enough to have seen all sorts of one-in-a-million situations and there are only just so-many Datsun blocks in the world. Honest wear also happens, seems like most A-series motors go 100-200K and I've driven more miles than that in my life, and who knows, the next owner might put a ton of miles on. I won't pass on a 1mm set of pistons that are cheaper or better than a .5mm, but if they are otherwise identical, it's nice to know the block can be rebored should something happen. Good to know the Datsun A-series is better. I mean, of course they are since they aren't British and have a real rear-mainseal and whatnot, but I wasn't sure if they were sufficiently rigid to not have excess oil consumption with overbored motors. Considering the majority of new cars ship with coated pistons, there is clearly something there.

They use heat-resistant on the piston top to improve efficiency, cooling, and reduce detonation. Anodize the ring grooves to reduce ring-welding, and coat the skirts to reduce friction losses and scuffing. Now I'm not worried about the ring issues, but lower friction and more heat doing work is interesting. I did see there are DIY kits, but I'm not convinced that one can really get the coating thickness even. I guess it seems to work though. Looks like they are milling golfball divots in pistons now as well to improve combustion. If I didn't have so many projects, I'd be tempted to DIY something on the CNC, but not for this motor.

Well, leaving some metal means if something goes wrong I can rebore the block rather than scrapping it, but some of it is habit. On the British A-series motors, you can bore .120" over, but anything over .060" over uses more oil when you step on it because the block and bores twist a bit. Not sure if the Datsun block is different enough it's not an issue. Are folks using piston coatings these days? Oh, I'll do the usual stuff, volume-match the combustion chambers, port-match the head to the intake and the header, polish the runners and bowls, etc. Increasing the lift without changing duration is why I was considering the roller rockers since they are offered in a wide variety of lift ratios, but I'm open to other ways.

The goal here is a warmer than factory motor with factory reliability, good efficiency, and good low-end manners, on the cheap(ish). I already do have a nice header, .25" over exhaust, and Webber on a flowed intake manifold for the car. I'd rather have a nice idle and have things get winded at 6K than something with a lumpy idle that pulls to 8K, mostly I've driven low-revving trucks so a screaming motor just isn't natural for me. I finally tore down the A15 bottom end I had sitting around. It had blown a head gasket a dozen years or more ago but had been running fine before the head gasket (and regrettably overheating to the point it quit running). Tearing it down the pistons did have some light scuffing, but not bad, three of the bores were in spec for a STD motor, but number 4 had about .004" of wear and lip on one side of the bore, so it's time for an oversize. I know it's unlikely I'll ever need to oversize it again, but since I'm already replacing a 1400 (which replaced the 1200 the car was built with) with this bottom end, I'd rather go with a smaller overbore and have stiffer cylinder walls than a couple extra cc of displacement. So, I'm looking for a .5mm or .75mm oversize I suppose. I'm also planning on replacing the H95 head with a H72. I've rebuilt some of the British A-series 1275 motors BITD, including some offset overbores to .080" or .120", but that's been decades so I'm pretty out of touch with what's happening these days. I have a CNC mill and boring head, so I could do the overbore myself or hire it out. If I do it, I'd be inclined to torque on a head and main caps and bore from the bottom to get the straightest bore job I could, but I don't own a honing machine, so would have to use a ball-hone after boring. Hiring a shop would be the other way to go, but they would likely bore and hone from the top and unless anybody knows a shop with a dummy-head to bore-through, then I'm sacrificing some straightness of the bore for a better hone job, so I'd be interested in what folks think. Local rents and labor costs are crazy and the A15 block is small, so I wouldn't even doubt there might be a specialty shop someplace I should mail this to that could be cost-competitive. As to pistons, cast are preferred and I have a very precise scale, so I'm content to do my own balancing work to match them and the rings. The ones used with the closed H95 head were offset dish, but I'm seeing some offset dish and some centered-dish pistons for sale, not sure it really matters for the more open H72 head? There's a huge price range on the pistons, from $120/set to over $1250/set. I'm only wanting just a bit over factory, so don't need anything crazy. The options I'm seeing on the cheaper end: Endurotek, offset dish, .040" over. ART Centered dish, .5MM over, comes with NPR rings Sterling .75mm over or this set from a forklift parts house, 1mm over https://forkliftengineparts.com/product/a15-nissan-piston-set-4-1-00mm/ Of course, I'm happy to have suggestions as well if someone knows of a good deal on, for instance a NOS factory set of .5mm pistons. As to rods, I have no reason to suspect the factory rods aren't fine, so my natural inclination is to polish and re-balance the factory set and reuse them. Still, if there were rods that didn't cost a fortune that had less weight or windage, I might be persuaded. I did see fancy rods, but they look heavier than stock for no reason unless you are trying to make a lot more power than I need. https://www.ebay.com/itm/275829147456 The crank looks fine in terms of continuing to use STD bearings, but I did plan on replacing the bearings since they saw some heat. Anybody see quality bearings around on the cheap lately? My lifters look pretty OK, but if I do have the cam ground, I assume I'll wind up with new ones. As to cam, something efficient and useful from idle would be the thing. Is there a more efficient cam than the factory grind? Pushrods. Anything to do other than factory? When I was building the British A-series, they were making carbon-fiber pushrods, but I gather those turned out to have real reliability problems. Roller rockers. Seems like the A-series isn't suffering from a lot of power loss to the rockers, so it might be hard to cost-justify roller rockers for a low-revving motor, but if I were able to (for instance) just use a slightly higher ration rocker with a factory cam to get more torque without sacrificing idle, then it might be a consideration? I'm also torn on balancing. I'll match the pistons and rods (big end and small end), but hadn't decided if I should clean the casting on the crank and send it out for re-balancing or leave it as-is. If I were to have it balanced, I suppose I should send it out with the flywheel, pulley, and perhaps pressure-plate as well?

I'm surprised at the rather abysmal mileage the 720s seem to get. Looking on the EPA website suggests about 20 for the 4x4and more like 27 for the 2wd and I was wondering why the vast difference, but to see people report it here seems to confirm those numbers as plausible. My Mitsubishi pickup got a reliable 29MPG and the Mazda PU owners of similar age report 30-40+, so what did Datsun do that was so different I wonder? I love the look of the 720, but if I'm going to get sub-20 MPG, I'll have to pass.

That's with the pig of an automatic transmission fitted I believe, I bet it's closer to 1500 with the 4-speed!

1979 210 wagon in the Moss Landing, California PNP. In a way it broke my heart since it was a straight and non-rusty wagon, I don't remember the last time I saw one with a decent body. Sadly the POs were treakers or something, the whole thing was covered in rattle-can paint and duct-tape. There was a 5-speed though, so I spent the hour pulling that as a consolation prize. 🙂 I'll go back for the tailgate and differential, and might just snag the A14 just in case I need a spare at some point.

If you keep the Hitachi then you want to keep the heat shield and spacer, these are useful in preventing your fuel from boiling in heavy traffic on a hot day and also from evaporating when you stop the motor so you will get faster starts. The Webber swap helps a ton in the mid-range, at the expense of several MPG.

I was going to chime in but non-unusually Mike has covered everything that needs to be covered. The only thing I *might* say is I've had brakes lock up after a block or so because they will apply but have too much rust/crud to release so either don't go far or pull the wheels, apply the brakes, and make sure they retract normally. After having some soft-lines that looked OK swell up inside to they didn't pass fluid I've started replacing all three soft lines as a matter of principle when rescuing a car that's been sitting.

So little info here... The 5-speeds are worth a premium over the autos by ~$800. Where to look for rust: bottom back of the fenders is the spot that almost always goes first. After that it's the back bottom corners of the front doors. Then it varies, sometimes it's around the front windshield and sometimes it's the tops of the wheel arches. Once again, no pics and no details = wild ass guess. That said, $2100-3500 is about the range I'm used to in this part of the world unless it's junk or particularly nice.

Pretty good chance you'll be replacing a decent chunk of the exhaust if you are doing a motor swap anyway. I lost my mind and had a 2" system put on a medium-hot A14 and it's WAY too much and sounds like crap. I wish I'd gone 1-3/4".

I recently did an "easy" swap, A14 into an A12 car, by the time I'd done the fabrication for the motor mounts, transmission mounts, came up with a solution for the exhaust, radiator hoses, figured out a way to squeeze in an electric fan, and all the other little bits I had the car apart for at least a month and it was longer before some of the other issues were sorted. In the end it cost a lot more in time and money than putting a turbo on the A12 and I would have had a faster car. I'm with Dguy210 in suggesting you work with what you have for a minute before pulling the pin on the engine swap grenade. The L20 swap will add a good amount of weight which will make your suspension and brakes worse and the A-series motor has room to grow from stock. If you don't have the electronic ignition, get one ASAP. Get a Webber and a header and you'll be able to enjoy the car a lot more while actually reducing weight. Speaking of, get a little sealed gel battery in there, $100 and shaves 30Lbs off the car high and far forward, if you are sensitive you can actually feel the difference it makes. Check that you have a decent flowing oval-port head, if not it might be worth the swap. a little bigger exhaust will help as well, don't go too big or it costs you torque you can ill-afford to spend.

I would strongly consider electrolysis for your rust removal, might be a lot quicker than a week.

Not golf cart tires but close, At work we have a little electric utility truck that is scarcely more than a golf cart and I was amused to find it riding on the same 155/80R12s that are factory spec for the 1200.