robox

I am working on my Z this winter, but last winter I rebuilt a motorcycle. I got much more "out there" with the design on my bike than I ever will on the car, and I spent lots of time in photoshop tweaking my ideas. I understand that not everyone reading this will have an interest in a motorcycle build thread, but the entire thread, including photoshop "mock-ups," is in the Honda XL600 link below, in my signature. And yes, I agree with the previous poster who commended your good photoshop skills. Cheers

Thanks for that. Good link. Mine definitely look similar to those. The only question I've got now is... what calipers are mine exactly? The numbers embossed on mine don't even come close to the codes mentioned in that link. Mine: 4 5P 11 Mentioned in the link: S12+8, S12W, etc. Only important, I guess, so that I can figure out what pads to buy, and rebuild parts if necessary. Cheers, Christian

I bought a pretty beat-up 260Z from a friend as a parts car. I bought it just on the strength of a few smart-phone pictures for $150. One of the selling points (in his mind, anyway) was that the car has what he calls "high performance" brakes. Now that I have the car, the only thing I can find on it that might conceivably be high performance is the front calipers. Does anyone recognize these? Any advice on whether they are worth swapping onto my '71 240? Thank you!

Thanks for clarifying, Madkaw. My ideas for approaching the implementation of a Subaru LSD R180 don't seem to be going anywhere, anyway, due to the lack of axle shafts in New Mexico junkyards and on ebay. Also, the Canadian seller of Nissan 3.9 R180s is out of stock for a few months. I guess I'm going to start looking for one out of a Nissan pickup in the meantime. In any case, no matter what happens, my thinking that this swap is something I would do "within days" has been modified to "within weeks or months". Oh well, there's plenty of other work I SHOULD be doing anyway.

You know, it's interesting... I went back and read through JohnC's thread, post by post, and for whatever reason no one in that entire thread engaged in the same kind of discouraging dissuasion of innovative thinking which is in evidence in the preceding post. I suppose that in retrospect its a good thing that no one did, given the fact that by all accounts he has engineered and brought to market what appears to be an excellent product, or if someone did in fact discourage him, that he chose not to listen. I agree that the Subaru diff is probably a nice upgrade (finding a new way to swap it in is exactly what I am contemplating, after all), and that JohnC's flanges look like a great way to go. Buying a set of those flanges is an option that I might even end up exercising at the end of the day. In the meantime, however, I will continue to mull over whether there is another, more affordable way to do it. Thanks.

The seller is being very cool, and is covering the return shipping. As I do my real work today, my head is submerged in trying to figure out how to make a Subaru 3.9 R180 LSD work for cheaper....

Yes... as I mentioned in Zedyone's thread, I eventually figured it out. I re-read his whole thread last night trying to wrap my head around the issue, and the spline count difference is not mentioned in that thread (unless I missed it). I guess its one of those bits of info that everyone around here knows so well that it's just not talked about. I eventually figured it out by reading the thread over on hybridz where the Wolf Creek flanges were developed. Thanks!

Well I received the Maxima differential. It's a good thing I popped off the rear cover to inspect the ring and pinion before I did anything else to it, because the ratio WAS NOT as advertised. It's a 3.54 (39:11). Now I have to send this heavy thing back on my own dime (I'm going to petition eBay to pay return shipping, we'll see how that goes). So I am back to square one. I've been thinking about the Subaru STI diff swap that Zedyone is doing.... I just posted in his thread this same thought.... why bother spending $500 for the Wolf Creek output flanges when it seems the output flanges from the outgoing R180 could just be used? Or a yoke with a splined shaft...? Are the spline counts different?

To revisit an earlier part of this thread.... Couldn't the $500 for the Wolf Creek flange-shafts be saved by either A) installing splined yokes, as Blue mentions here, and then replacing U-joints to mount up the rest of the 240 half-shafts, or for that matter just re-using the flange-shafts from the original R180 that is being replaced? Even if opening the diffs were required to swap in the threaded buttons, it seems like a good way to save a bundle of $$. Am I missing something here? That seems like the obvious and cheap solution. EDIT: Never mind... I just figured it out. Datsun spines are 25 tooth, Subaru are 27. Bummer.

Yes.. that is a super-informative link. Thanks Madkaw. Looks like a fun operation. As I am also a machinist, I'm going to at least investigate the options of doing a little machine work to see if I can leave intact the R180 3.36 that is currently in my car, thereby leaving it in a sell-able state. I will know more when I get the parts in hand. We will see. Cheers, Christian

Cuz I'm impulsive of course! And because I trust that I CAN work out the details! Anyhow, I did a bunch of reading of other older threads and learned that it's no big deal. Just gotta open the two diffs and swap a few parts, specifically the "threaded buttons" which permit the use of the OEM 240 halfshafts. No idea what those buttons are at this time, but I am sure I will know soon.... Looks like a good link... I will read it. Thanks!

I went out in the 240 for the first time, really, since installing the 5 speed and fixing the speedometer and tachometer. It was very informative. The car definitely felt anemic until about 2750 rpm or so. And in 5th gear, I couldn't really even get it up to that range, unless I was going somewhat downhill. I promptly went on eBay and bought the Maxima differential (R180 with 3.70 gears). The price was more within my range than most of these other options. My question, for anyone who might have the answer or some input, is what sort of challenges am I looking at as far as getting the half-shafts to work? Here is a picture of the Maxima diff I just bought: As you can see the U-joints are quite different from what the Z has. I just haven't worked on enough cars yet to know if this is going to be a lot of work. But it's gotta be doable. For what it's worth, I do have a set of half-shafts sitting around from a 260Z parts car I got recently.

Thanks guys... tlorber, I just saw an R180 with 3.70 gears from a Maxima on eBay. The driveshafts look different... well specifically the U-joints (or CV joints, not sure what the proper term would be) look different. How much work was required to make that diff work in the Z? 3.70 seems like it would be a good ratio. Thanks

Hey Zedyone- No.. actually I did not see your thread... HA HA! I guess that's because when I started my little thread I was just thinking along the lines of asking for advice about gearing options. The topic of swapping in a Subaru diff had not yet crossed my mind, so I wasn't looking for that kind of thing. Anyway I just read your whole thread. Tons of great info in there! I can only assume that people are willing to drop something like $1000 to do that swap because of the limited slip. I agree with one of the posters on there that $500 just for the output flanges is a tough pill to swallow. For me personally, limited slip is not worth that much $$. I basically just want a different gear ratio in the rear end, and a $600 R180 that will bolt up easily is more like what I am thinking. At this point, though, I need to drive my car some more to see how much I really care. I am going to be more interested in freeway driving than burning rubber, so the 3.36 I've got now might be just the ticket. Or who knows, maybe the 3.54, which seems a bit easier to get one's hands on, might be a good solution for me, given my driving preferences. Thanks again for that good thread. I gotta go back and re-read it to try to figure out what the "RT mount" is... Cheers

Thanks guys. Mitchell I see that you have a 3.9 R180. You say you got that out of the front of a pickup? Cool. There are 3.9 R180's on eBay that are coming out of Subarus.... they look similar to the Datsun variety except for the output flanges... there aren't any flanges! Could those be made to work? The truth is that I have driven my 240 a grand total of about 3 or 4 miles since installing the 5-speed trans, so I am not sure how much the 3.36 gears are going to bother me. But what I don't want is to be out of the L28 powerband in 5th gear, needing to downshift to 4th to go faster or whenever I encounter a hill of any sort. Starting to take the Canadian R180 3.9 option a little more seriously, as options for this diff seem slim....

Car: 1971 240Z with an L28 engine and a "wide-ratio" 5-speed trans. Still got the original R180 diff with 3.36 gears. I've read elsewhere on this forum that: "The early five speed and 3.90 happens to perfectly match the power peak of an L28 curiously" This suggests to me that it might be worthwhile trying to find a 3.9 diff to take full advantage of the L28 and the transmission, but as most of you probably already know, they are not so easy to find. Also, I can't wrap my head around why it would be good to go to the R200, due to extra weight and extra work. There's an eBay seller in Canada who has the R180 with 3.9 gears for about $560 shipped, which is quite high in my opinion. I guess another option would be to try to find just the gears, and swap them into my diff, although those gears are probably just as hard to find as the diff itself. I could go to 3.54 gears, but it's probably not worth the trouble. Any advice is welcome... Thanks! Christian

I "hot-wired" both of the later tachs I have sitting around, and found that one (and only one!) of them works. I looked at the date stamps and figured that one (not working) is from 1974 (probably 260Z) and the other (the one that works) is from 1978 (280Z). Anyway I have already swapped the internals from the working tach into the body of the 240 tach and tested it in hot-wire mode, and it works! Thanks again Blue for that good writeup. It's really a very easy operation. In the process of wiring up the new tach I learned that the wire which is supposed to be switched +12VDC (red/black IIRC) was not hot, no matter what I did with the wires emerging from the harness up near the coil. So who knows, that might have been the problem all along. I decided to skip the tach harness connector plug altogether and just run a 3-wire cord from the back of the tach up to the coil and do the appropriate connections there. I have not yet done that (ran out of time to work on the car for now) but I am confident it will work. I will update to let everyone know how it goes... Thanks again!

Oh, and also... my flamethrower coil is 3 ohm. Currently set up with Pertronix (I changed it this morning) and NO resistor. I think that's the right way to go....

Well I spent a little time playing around with the wiring and with different configurations, both with points AND with a Pertronix module. I got the car running in a few different configurations, with and without a ballast resistor. However, in all cases the tachometer went immediately to redline limit as soon as the key-switch came ON and stayed pegged there until the key went OFF. I suppose my next step will be to transplant the guts of one of these 260/280 tachometers into the body of the 240 tach, as described in Blue's excellent write up. I'm going to study the write up to see about "hot-wiring" the individual tachs with jumper wires to verify that at least one of them works first. Do I understand correctly from Blue's write up that the white wires on the 4-wire 240 plug are just wrapped up and not worried about? Thanks! Christian

Thanks for your reply, Blue. The diagram you included above is certainly the clearest, easiest to read drawing of this wiring section I have yet seen. However I am still a bit in the dark about how to handle the lack of a ballast resistor on my car. I'm thinking that the resistor must have been deleted on lots of other older Z's, so this question is probably not a new one, and it's probably been successfully answered before... Can I just bypass the resistor and connect the GW wire to the red wire? I should probably just start playing with the wiring on my particular car, with the aid of some jumper wires, and see if I can get something going... Also thanks for doing (and linking) such a good writeup on the 260/280 tach upgrade. I might end up doing that if my original one proves to be toast. Christian

I've been studying the wiring diagram, and it seems significant that my car no longer has a ballast resistor. I've noticed that one of the wires goes there, supposedly. So, any advice on wiring the tach properly without the resistor would be most appreciated. Thanks! Christian

I will start off with the following disclaimers: • I know next to nothing about how tachometers are supposed to work or be wired up. • I have read a few threads on here about tachometers. I have learned a few things, but also reinforced the awareness that I don't know much. • I have not yet found answers to my questions... The basics: Bought a 1971 Z from a couple of dopes who knew nothing about the car. I am going through it trying to learn about it and fix things as I go. The car still has points in it, although it also has a pertonix flamethrower coil. The tachometer needle was off the pin, sitting in the bottom of the gauge. For this reason I never knew if the tach was working or not. Yesterday I pulled the tach out of the car and was able to re-install the needle. I plugged in the 4-pin connector and turned on the ignition... and the needle went all the way to the redline stop and stayed pegged there. No change when the car was running. When the key is turned off, the needle goes back to zero. It is an early, 4-wire tach. I do not know where the wires on the other side of the connector are supposed to go, although I understand some or all of them go the the coil and/or distributor. I have two later-style tachometers sitting around, with the multi-pin connector that handles the tach as well as the lights (I guess those are called 3-wire tachometers). • Does the "jump-to-redline" behavior of the tach suggest a broken tach? Or bad wiring? • Is there an easy way to hook up the tach in the engine bay with jumper wires to see if it's working properly? • Should I, alternatively, try to use one of the later-style tachs I have sitting around? (I have a small preference for NOT doing this, as the style of mounting the gauge is different, as I am sure you all know) This stuff has probably been covered before, but I couldn't find it. I am not offended by links to other threads with relevant info. Thanks in advance for any help! Cheers, Christian

Thanks for the replies, guys. Zed Head, I had to read your post several times to understand it, but I now do. As to whether the pointer is from an early 240Z and should be pointing on the other side... I have no idea. I've been working under the assumption that, as previously noted, this damper appears to be from a ZX (a totally different engine). This also explains why the damper has 3 V-belt grooves while my car only appears to need one belt. I've also been assuming that once I pull the damper off the front of the crank, something will be revealed. I just haven't gotten around to doing that yet (more on that in a minute). One other thing.... Zed Head you mention the following: I have read about this in my ancient Chilton's manual, and I cannot make sense of it (although I'm sure it's old hat to you guys..). The last time I had the valve cover off I spent 10 minutes with a flashlight looking for the groove, or even just trying to understand what the "cam plate" is.. and I was mystified. Any explanation or photos would be appreciated. And Madkaw, I have the car somewhat disassembled at the moment so it may not be a bad time to investigate the oil pump and distributor shaft... I just don't really know what I should be looking for... not sure how to tell if things are lined up properly or not. I guess I should study the FSM because the aforementioned Chilton is not all that easy to understand sometimes. After getting the engine running at 36º - 38º advance (what seems to be 6º - 8º advance) I shifted my attention elsewhere. I have had a 5-speed tranny sitting around for a while (without a shifter), and also the car has had a generous oil leak coming from near the rear of the engine. I decided that since the car was in the shop, I might as well get a few things done. I machined a new shifter for the 5-speed out of stainless, pulled the 4-speed, the clutch and the flywheel. Bought a new clutch, had the flywheel resurfaced, bought a new rear main seal. When I went to remove the old one it was spinning freely in there... not really "attached" to the block at all! I'm thinking that was the source of the leak! Also pulled the oil pan to re-seal. However, then the storm hit, the temps dropped (my workshop is poorly insulated... COLD in there right now), AND I got sick. So that is how the car sits... drivetrain somewhat disassembled waiting for me to feel better. The storm has also, I think, interfered with me getting any new info about the parts car I mentioned earlier. I will read up on the oil pump and see about checking it. Info/insight on "cam plate" and notch appreciated. Thanks!

Thanks again for passing on the timeline link. Very informative. I haven't pulled the damper off yet to see if there is a real problem there, but it seems like a reasonable possibility that the "clocking" attachment method (i.e.: spline, keyway, taper... I just don't know what's in there yet) is machined differently on the ZX damper such that the pointer is 30º off from what it's supposed to be. Sometime soon (I think tomorrow) I will get some pictures and other information about an S30 (240, 260, 280... don't know yet) which is not much more than a parts car, but could be mine for the taking. Who knows... maybe it's got a good damper on it? (And bumpers and headliner and roof and door handles and tachometer and.... all the other stuff I need for my car!)

Thanks Zed Head. I love forums!