Zed Head

The seller left too many things undone and set his reserve too high. No sale.

Oops. My memory was that there was something different. Got the times wrong. When did Nissan stop calling any of their cars Datsun? In other words, when was the Datsun name retired? Wikipedia says 1986. https://en.wikipedia.org/wiki/Datsun#:~:text=When Nissan took control of,Datsun brand in March 1986. I should have looked at the pictures.

An orange Z is up today. Seems like it should do well. Survivorish. Good start for a resto maybe. https://bringatrailer.com/listing/1972-datsun-240z-165/

Seems like they'd know that it's a Nissan 280ZX. It is nice though that the ZX's come up with a "Datsun" search. Easier.

Also amazing that they apparently worked fine.

We're just starting at different ends of the spectrum Racer. You're at "this is how it's normally done". The "right way". I'm at "what is possible" to be done. Look at that big block main bearing cap and you'll see that there are possibilities outside of normal manufacturing specs.

I'll stop after this. Here's a cap surface that looks kind of knurled. But it's just a factory machining flaw. The engine ran. Good info in the article though. https://www.enginelabs.com/engine-tech/enginelabs-blueprint-series-the-keys-to-proper-block-align-honing/ (Right) JGM’s owner, Ryan Peart, showed us this big-block Chevy main cap out of a running truck engine...

This moved "Edit" button is really screwing me up.

Fun topic. p.s. I think I've been using "journal" incorrectly. Replace all of my "journals" with "saddle". https://www.mahle-aftermarket.com/media/local-media-north-america/pdfs-&-thumbnails/cl77-1-205r.pdf

Valve guides and pistons experience friction and wear from movement. Main bearing saddle journal knurling just raises a static surface so that the actual bearing can be placed on top of it. It's a different application. I'm not saying anyone should do it, I'm saying that it should be possible and has decent odds of working. As shown by the apparent fact that people do it. There's a difference between following instructions and understanding enough to write them. No offense. Kind of surprised at the resistance. Here's some ingenuity. Seems outside the "accepted practice", but apparently it is okay in their world, but they know what they're trying to achieve. And they had a deadline. https://www.enginelabs.com/engine-tech/blueprint-series-measuring-and-setting-bearing-clearances/#:~:text=Never mix bearings of different,the proper housing bore diameter. "Some performance bearing companies like Federal-Mogul offer optional bearing sizes such as 0.001 undersize or oversize inserts that make it much easier to set an ideal clearance. In our case, we needed 0.011-inch undersized on some of the journals and 0.009-inch-undersized bearings for the front two. Federal-Mogul offers these and saved our bacon. This allowed us to increase or decrease the clearances to get closer to our ideal. While mixing half-shells is acceptable practice, never mix shells with more than 0.001-inch spread and always stay within the same manufacturer. In other words, never mix a 0.009 bearing shell with an 0.011-inch version. One down side to performing all these customized clearances is that we were faced with purchasing two (and in our case, three) sets of main bearings for one engine. So do all measuring before you buy the bearings. The same is true with rod bearings... The best way to fix this would have been to have the engine align honed to establish the proper housing bore diameter. In our case, the engine had to go back together due to deadlines beyond our control so we did the best we could. The final 0.0035-inch clearance is well within factory tolerances, but it is also 0.0005 inch wider than we would prefer..."

Open your mind, just a bit. Imagine. Where's that racer's edge? It's a thing. https://www.google.com/search?rlz=1C1SQJL_enUS862US862&sxsrf=ALeKk01ZNoDPG6LyF_XQ9GV88CT2vdY9Ig:1619128301557&source=univ&tbm=isch&q=knurling+engine+block+main+bearings&sa=X&ved=2ahUKEwiw54n66pLwAhVQjp4KHdTGCOQQjJkEegQIChAB https://mysql1.racingjunk.com/Engine-Machining/184133622/Main-Bearing-Cap-Knurling-Tool.html How about shims? https://www.speed-talk.com/forum/viewtopic.php?t=28780

The lemon-green 73 didn't sell at $28,749. Silver is the color of the month. A 2+2 77 got $35,000 the other day. https://bringatrailer.com/listing/1973-datsun-240z-156/

I noticed that too. But the blue roll cage bars are there. It has a Rebello motor. It's funny how these guys just don't know how important the sound of the engine is. Nobody watches a race car video for the music. Thousands probably left on the table. You'd think they'd watch a few auctions and figure it out.

Here's another place to call. They might have some advice. http://www.rebelloracing.com/index.htm

Not your typical tow hook car. There's a 72 under there somewhere. There's a driving video with spooky 60's surf music. The video seems like it's 1.5 speed, also like one of those 60's race car movies. https://bringatrailer.com/listing/1972-datsun-240z-174/

For the record, I just swapped a spare engine in to my car because I had one and did not want to rebuild the head on the engine that was in it. These things depend on what the owner is trying to accomplish.

I'm sure that you realize that any good machinist who heard you say that would take that as a challenge. Machines are just metal formed to do what we want it to do. There are pros and cons to everything. https://www.practicalmachinist.com/vb/general/knurled-bearing-fit-how-engineer-324497/ If the machinist has to work on it then does it really "do"? A good machinist could just copy one of the existing caps to steel and get a perfect fit from the start. Remix doesn't even need a used part.

A modified 71 is on now. Not sure, the wheels seem too dark. No reserve and it's had a lot of work done to it. Probably interesting at auction end. It's in Greece and has been on BAT before. https://bringatrailer.com/listing/1971-datsun-240z-20/ https://bringatrailer.com/listing/1971-datsun-240z-170/

Another good number for a modified 73. I think that "it just looks right" is a factor in getting a good price. https://bringatrailer.com/listing/1973-datsun-240z-155/?utm_source=dm&utm_medium=email&utm_campaign=2021-04-21

Seems like a good time to think about how main bearings work. Materials, sizing, all that stuff. I remember learning how to use Plastigauge in high school auto shop but I don't have many memories of what to do if the numbers are off. Seems like all of the videos I've seen all have good results, nobody ever gets a bad number and has to fix it. Plastigauge has always seemed more like a confirmation tool than anything else. It would be interesting to know what people do if they get a bad clearance. Can you knurl a bearing seating surface to shrink a wide clearance? Seems like it should work. How do you tell if the bearing is square in the seat? If Remix tries different cap does he need to worry about squareness, or concentricity or roundness? Do any of those change over the of of an engine block? Don't know, just asking... It might be that manufacturing QA was good enough in the 70's that caps are swappable. Who knows. Found a couple of links. Looks like one "borrowed" from the other. https://www.substech.com/dokuwiki/doku.php?id=engine_bearing_materials https://www.chevyhardcore.com/tech-stories/tech-choosing-the-proper-bearings-for-your-engine/

$24,500 for a 78 2+2. Life is good in Z world. Clean and neat car. I think that the door bumpers that many people hate actually help the 2+2 lines. https://bringatrailer.com/listing/1978-datsun-280z-22-10/

Rockauto only shows standard size. https://www.rockauto.com/en/catalog/nissan,1976,280z,2.8l+l6,1209226,engine,crankshaft+main+bearing,5220

Nissan sells oversized bearings. Not sure if they're meant for crankshaft or block. Maybe they're bendy enough for either. Probably want to see if they're available. http://www.carpartsmanual.com/datsun/Z-1969-1978/engine-280z/piston-crankshaft/17 http://www.carpartsmanual.com/datsun/Z-1969-1978/engine-280z/piston-crankshaft I'm seeing that it's probably doable but might not not worth it since another complete block should be easy to find and cheaper overall. https://rigiboreinc.com/articles/38/a-new-dimension-of-control-in-crank-boring-with-rigibores-auto-compensating-line-bar https://www.enginebuildermag.com/2006/06/line-boring-equipment-a-boring-subject/

For the record though, you can buy main caps for a Chevy small block from numerous places. You might call somebody like Datsun Spirit or Arizona Z Car, if you decide to try to save the block. They build engines. Might even have some used ones. https://www.jegs.com/i/Speedmaster/746/PCE289.1002/10002/-1?gclid=Cj0KCQjw9_mDBhCGARIsAN3PaFNMd6jy7Ofu06P4cJsdCpPw58lu4UozC605W25FcJdrOXT8lkmMhT4aAjA4EALw_wcB https://datsunspirit.com/ http://arizonazcar.com/

I think that the caps are considered part of the engine block. Not shown as available as separate pieces. A guy could probably go to a wrecking yard and find one then have a machinist make it work. But, it's still going to come from a used engine. I'd have the guy search his garage for that cap. http://www.carpartsmanual.com/datsun/Z-1969-1978/engine-280z/cylinder-block