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Ok. Well, thanks very much for the info you provided... which you didn't have to, and I appreciate it. I've been talking to my engine builder and thinking about the initial engine start experience a lot. My engine didn't fire immediately, but I was very cognizant of not turning over "too much" as I was told that assembly lube only protects for a bit... then engine oil pressure needs to happen. And yet... So... here is something everyone who builds a L series (or buys a rebuilt one) needs to know - and it is my main takeaway from my unhappy experience. At engine cranking speed, there is not enough oil getting to the cam and rockers... on an L series. Period. Freshly rebuilt motors with dry oil passages? That... times 10! When newly rebuilt, these engines NEED to start quickly. That is, you can not crank newly rebuilt L series engines for extended periods of time... or many short periods of time. If it doesn't start within a few seconds. STOP, and find the problem. Yes, you have to have everything lubed and in my case, everything was... properly. And even though you have everything lubed with the trick-est lube on the planet, if you crank it over many times without it starting - you absolutely are making a mistake - one that may cause cam and rocker failure in a hurry. As MadKaw has discovered, the stock spray bar set up is not ideal. At cranking speed, it is basically doing nothing but waking up from a knap. And, It is sitting on the passenger side of the cam towers with its holes pointing (at best) at the "back side" or the valve closing side of the cam lobe. The loading from the spring and valve while closing is much lighter than on the opening side. Spraying oil onto this side of the cam is not optimal. Spraying oil at the front side, or the opening ramp, which is the high load side is much better. And yet more, if your cam is drilled for internal oiling, check out those oil hole locations on the lobes. Half or more of them are in very sub-optimal locations instead of spraying the pad just before the front side of the lobe comes into contact with the rocker pad. Now, at engine speed - let's just say 3000 RPM for example, the oil coming out of the spray bar and the holes drilled in the cam is coming out big time. There is lots of oil everywhere, and it is getting whipped all around, and in fact is creating a fog of oil inside the valve cover. Though not optimal, as discussed above, at speed, it is adequate. Turning over at starter speed? Not so much. I pulled the rockers and cam from the car today. The silvery stuff on the cam lobes is not the rocker pad material transferring from the pad to the cam. It's very tiny flakes of cam that are now gone... due to lack of lubrication during initial start up. Since the cam is nitrided, and should as a result have a "case" that is hardened beyond .015 - .020", I am going to send it off to have it polished just enough to clean up the lobes (I estimate .001" max). The rocker pads will be resurfaced as well. When I get it all back together, (with lots of lube) I will have my starter fluid ready.

I have been talking to the engine builder and he was saying the spray bar should optimally run on the other side... How much for the spray bar - to the U.S.?

Wow. This is hard for me to believe. So I need a new cam and rockers... or to resurface these rockers... Any chance that because this cam was nitrided, I may be able to polish the lobes and salvage it? I mean, the case of the part is hardened up to 0.65 mm (0.025") in depth during the nitriding process. Maybe after polishing them to mirror finish, I could still use it with the same rockers (once they have been resurfaced, of course)? G

Ok. Good to know, and I feel better about the "internal oiling + spray bar" issue as I am using a known good turbo oil pump. Thanks for the input. If you look at the third rocker picture (going down the page), you might be able to discern the spot where the cam lobe wear spot stops. I looked closely at each rocker and can see that the lobe is not running off of that end. I do note that we could have "cheated" a bit more towards the passenger side and picked up a tad more effective lift, however. Yeah, I hear you on point #2. If I was the test mule for this cam, I never would have gone for it. But, Kinetic used this set up in race winning engines - a long time ago, so there is some history of success here. I will have to check with them though about valve spring life. I am sure since this is a race setup, they wouldn't dream of sticking in a car and running it 50k miles. And I shouldn't dream to either. Probably need to buy a spare set or two now assuming I still can.

Before I removed the one rocker I took a picture of, I checked the valve clearance on a few... 3 to be exact. .25 mm and .30 mm were the feeler gauge sizes. I forget which is for intake and which is for exhaust, but I was just doing a quick check. Two of the clearances I checked were intakes and one was exhaust. The .30 mm fit in one only. The other two accepted the .25 mm gauge. So, seeing the clearances were close, I obviously moved on rather quickly to pulling one of the rockers for examination. No dark areas on my rockers. Heat like you experienced did not occur with this engine. Sorry to hear you have had such major problems. I know that has been difficult to deal with after hoping for a nice experience from the new engine. I had come across the posts about zinc before in the forums, but since my stock cam and valve train (old engine) had been rebuilt in the 90's and run for many ten thousands of miles over the years with absolutely no issues, I really didn't feel the need to invest a lot of time reading about it. Definitely more interested now... My engine builder is pretty top notch, and I know he used cam lube. I just haven't bothered calling him to see which. I found an assembly pic that shows the cam lube... Thanks... I am running a "high capacity" pump which is most likely a 280ZXT pump. I bought it from Malvern Racing - (Datsun Competition dealer) back in the 90's, and ran in my 4 cyl. 510 motor for a long time. For this engine build, we took it apart and modded it a bit for improved flow. Instead of running the high pressure spring, I run with the standard spring and a washer (used as a shim to bump the pressure up just a tad). I'll definitely need to check the spray bar for flow issues. Since all the lobes are looking very consistent with regard to the amount of deposits on them, it would seem my problem is also very consistent. I'll also need to check oil pressure across the engine operation spectrum. Perhaps I don't have enough pressure for 7700 RPM. I don't think that is a problem, but it I have not checked it. The rule of thumb is what 10 psi per 1000 RPM?

For clarity, were you saying this about my cam and rockers or about Lazeum's? I think my cam and rockers are still quite useable though they need some attention. Also, can you explain this part some more, as seeing "a cam do it on the bench before it was started" sounds very interesting. What is "it" and can you explain "and was picking up when turned over setting up the rockers." Picking up what? If you are referring to my pictures and not Lazeums, please let me know.

Oil is Mobil 1 - the full synthetic 10W30 stuff. I would have thought Jim Thompson from Kinetic Motorsports would have raised a concern with regard to getting the camshaft nitrided. I just now sent a note via their contact form asking about the issue, and will see how that goes. I tracked down some of my emails with Kinetic where we discussed the nitriding... Here are some excerpts: "The cam blanks used by our cam grinder have never been "CWC" blanks. Though Kinetic has tried Nitriding and Parkerizing in the past, the fine polish finish on the lobes has worked best for lobe durability. I asked Jim to confirm the cam grinder used the same cam blank (Estas) as usual." And from the same email thread: "That said, as it stands now, I would feel more comfortable with a Nitride treatment, but I don't want to ruin the fine finish on the lobes if that is beneficial. You guys are the experts, just tell me which way I should go. The couple week turn around won't be a problem for me because the car is down for the winter. How should we proceed?" So summarizing: Cam grinder: Kinetic Sunbelt (actually subcontracted) Shaft material - don't know for sure, but cams used by Kinetic Motorsports (cam blank is Estas) Nitriding done on cam only - I am not sure of the type - totally guessing it is ion nitride instead of ammonia gas for less warping No break in lube - just assembly lube - and I can get that info if needed. Oil used - Mobile 1 full synthetic 10W-30 No ZDDP or any other additives.

Took me a minute - Wild Ass Guess... I pulled my documentation from the build. These springs are custom spec'd for the cam. Here are the specs: 7700 RPM max - One spring only on intake and exhaust Intake: Installed at 1.680" with 54 lbf. Open height = 1.130" or .550" lift with 193 lbf. Exhaust: Installed at 1.680" with 54 lbf. Open height = 1.130" or .550" lift with 193 lbf. Actual build notes: Springs - 1.700" - 1.705" = 58 lbf in valve spring checker Seat: 1.710" = 56 lbf Open: 1.160" = 190 lbf (.550" lift) .578" to coil bind - minimum So, is that difference .578" vs. .550" ok, or tight? Valves are Manley stainless, retainers are titanium.

Looky what I found - I just assumed it was gone on the road somewhere, but when it came off, it managed to shoot out of the motor hard enough to land on the passenger side frame rail and get caught there. Anyone see anything unusual about it? I'm not feeling great about the job I've got ahead of me of taking the engine out and installing the u drive screws... especially since there is a welch plug behind the front timing cover. Using a hand drill to drill holes in the assembled block for these screws... Ugh.

They are new OEM... at least, they came in Nissan boxes, and wrappers... off of eBay. Any way to tell by looking at them? Oh, and the cam is internally drilled... and I have a good functioning, stock oil spray bar. Shouldn't be any issues running with both from what I researched... but now I am wondering if there isn't enough lubrication. On my 510, I couldn't run more than 460 lift without adding an external spray bar. Is it possible, that with internal drilling and the spray bar that this high lift cam is not getting enough oil on the lobes? The problem is on all cam lobes...

The new engine has something like 500 miles on it. So, I took off the valve cover to inspect everything, and adjust valve lash. Really surprised by what I am seeing here. Something is wrong, but maybe it is minor. It appears to me that the rocker pads are depositing material onto the lobes of the cam. Take a look at the pics. Lobe #12 Lobe #10 Lobe #5 I think the silvery stuff is coming from the rocker pad. When I run my fingernail over it, it has a noticeably rough texture. Here is the number 10 rocker from different angles: There is visible wear on the contact surface (though slight) on the "opening" side. As you can see by the profile view, it is not very much. I took pics at just the right lighting so you can see the wear edge. So, why has this happened? I know the rocker geometry is right - the wear patterns were checked during assembly and they are looking good now also. The camshaft has been nitrided... could it be that the hardened/nitrided surface is causing this? On first engine start, I ran the engine for 20 minutes at 2000 RPM for "break in" even though with a nitrided cam, I don't think it was necessary.

Separately, If I understand what is written in the Mikuni manual correctly, the bypass circuit is changing roles at the point where you go WOT to somewhat address the situation where the mains haven't come online yet. The bypass consists of the 4 little holes in the roof of the carburetor bores, just in front of the throttle plates when closed (and somewhat overlapping the edge of the throttle plate). Before the throttle plate opens to WOT, when the car is idling or has the throttle plate closed, these 4 holes are letting some air into the pilot circuit (there is a tunnel which is part of the pilot circuit, running along the bore in the carb body casting) which already contains a mixture of air and fuel, and after the throttle plate opens to WOT, flow actually reverses direction... so instead of letting air in, these four holes release air fuel mixture out (again, this mixture already metered by the pilot jets). Oh, and the fuel pump jets are also sending a stream of fuel for a brief period just after WOT too. A lot of people have talked about the lean spot that they can't get rid of at the transition point from pilots to mains. I have a theory that they are setting the initial throttle plate position too far open at idle... opening the throttle plates far enough to activate the bypass circuit - to bring some air/fuel mixture out of one or possibly more of the bypass holes (1.5 maybe?). And this is contributing to their selection of too small a pilot jet as well. Hard to say for sure at this point, but just before my engine lost the freeze plug the other day, I reset my throttle settings completely making sure not to open the throttle screws any more than 1.5 turns past when they touch the throttle lever. I don't recall exactly, but they may be closer to 1 turn. And doing the same with the pilots too: 1.5 turns max. I warmed up the engine, and then sync'd the carbs by first disconnecting the adjustable throttle arms... and making minute changes to the throttle screws. Then I set idle at the highest RPM I could achieve while also watching the AFR. I was adjusting the pilot screws in increments of the screw driver slot width... in the screw, to get the final setting. With the 57.5 pilots, I ended up at something more than 1.25 and less than 1.5 turns. I need to look at the data from the runs, but I think my lean spot has been resolved. I guess after this long post, I should have confirmed already. It's too late at night for me to look now, but I'll check to confirm when I can.

I don't track or log manifold air pressure. I followed you up to here: Did you mean 'At 0" mercury' in this instance? This zero manifold vacuum is essentially just after going WOT, before the engine has had any time to speak of to react, right? The way I envision it is, at this point, there is really not enough draw on the main venturi to bring fuel up through the main fuel jets, into the aux venturis and out into the bore. If I have this right, then I follow. And, I'll certainly try some larger air correction jets when I can.

Just read the whole thread here... Thanks for putting all the time and effort into it and sharing as you went. Absolutely awesome... you appear to be a crazy as I am when it comes to finding solutions to things that bug us enough. I rebuilt my late style ZX box a few years ago. It was the first tranny I ever rebuilt. I took on this endeavor because the first to second shift had soured... on high rev shifts from first to second (~6k in first), it was delaying too long, and if I forced it, it would grind. I also figured the odds good it had over 180k miles on it. I replaced all bearings (including needle bearings) all synchros and a some misc. parts (like the "bushing" the needle bearings ride on) - all with factory parts. I certainly replaced more than necessary, no doubt as I had no idea what I was doing. I used the FSM (factory service manual) every step of the way. All the clearances worked out to be within their required ranges - I never even came across any info that anything might have to be lapped. I noted that the "teeth" on second gear - the ones that the shift sleeve engages, were "worn" like those on your second gear. They didn't look horrible, but not like the other gears either. I debated at the time whether to buy a new 2nd gear, or to file the existing teeth because I had no idea how "bad" mine was. I ended up not being comfortable with the price of the new gear, nor the unknown damage I might cause with filing. I hoped for the best that the new synchro would eliminate my main problem. I put the rebuilt box in the car, and the 1st to 2nd shift was much improved. There was still a very slight hesitation, but it wasn't annoying at all and only there with full 6k+ shifts - with no grinding. (Some autocrossing - some track days - no issues)... Then fast forward a few years... Recently, I got my new motor running. This one is revving past 7k, and the problem is back... BIG time. Those extra RPMs are a real problem. My feeling is that a new second gear will solve the problem - as those teeth (what are those called?) looked to be the most worn part of the tranny last time around, other than the reverse idler gear, of course. So, when I started your thread, I was pretty excited to see where it was going to land. But, now having read it through, it seems like you started with the problem I have, and transitioned to a 3rd gear crunching problem (which congrats! you solved) by the end. But I don't quite recall exactly how you fixed the original problem. So, is the first to second delay/crunch problem completely gone - even with your "old" second gear? If so, what do you attribute that fix to? My assessment from what I just read is: a factory synchro instead of an aftermarket one? And scuffing the brass off of the shiny surface the synchro mates to on the second gear? Anything else? I was about to place an order for a new second gear tonight from nissanpartszone, when I went searching in this forum to see what there was... (and I see now it may be on BO? ). And if it is on BO, then I won't be able to solve my issue with that solution, if that would solve it, that is. Also, I was looking at the reverse idler tonight on a spare tranny I've got... It looks reversible. Anyone know if it is for sure? Sure would be nice to swap that mangled mess on one side around to the other and put a fresh side into action. G

"Sound like air corrector with the repich on top activity, agreed." I'll give that a shot when I can get back to testing (blew out the Welsh plug). So is it just another myth that the Mains and Airs are typically close to each other? For the runs above, I was using 180 Mains and 220 Air Correction.

Which method are you referring to - just installing the welsh plug with some Permatex? I have an "18-22 lbs." Stant radiator cap. Any idea what stock rubber radiator hoses will handle? I have rubber upper and lower - though I have a Jags That Run (JTR?) radiator kit that utilizes some metal connector sections in the middle of both the upper and lower hoses. I am told the "rivets" in the pic I posted above are called "U drive screws". http://www.smithfast.com/udrivescrew.html I'll go ahead and clean the opening and install a new plug. Then, I'll fill up the cooling system with water so I can run the engine a bit and do a couple of tests... before I pull the motor out of the car and install U Drive screws on each of the plugs. Garrett

In this case, I got the plugs from Nissan. Of course, it is possible that it wasn't installed correctly but that brings up the question. How does one install them correctly? Is there a trick to it? The engine builder said he uses a 1/2 drive socket of a suitable diameter to fit inside the cup... but as close to the walls as possible. And he has a old 3" long, half inch drive extension that he doesn't mind beating on with a hammer (or something like that). He also said he put a little bit of Permatex on there. I think you can see that in the pic. Could the Permatex be a problem? I wouldn't think so...

When I have had time over the last month or so, I've been working on tuning my freshly built engine. I'm using a wide band O2 sensor. I had just recorded a few runs to the Innovate LM-2 SD card. I pulled off the interstate and swung around to the on ramp on the other side to go the other direction. I stopped on the side of the on ramp... pushed record, and eased away in first. I ran through the first 3 gears pulling just north of 7000 in each gear... I slowed down and merged onto the interstate and stopped recording. But within a 1/2 a mile, I noticed some very light smoke spiraling off the right rear of the car. Since the exhaust is on the left, I really didn't know what it could be. I pulled over, popped the hood and ran to see what was going on. Immediately I see fluid around the starter area. I wipe some with my finger and smell it - it is coolant. I yanked on a couple of the hoses, but didn't see any coolant spurt out. The hoses looked fine. So, not knowing how much coolant I have lost, I run to check the temp - (the car is idling) and see the guage is at about 240 - definitely south of 250. A tenth of a second later the car is off. While I am waiting for the car to cool down, I keep looking until I see the problem: So... how the heck?! I've never heard of anyone experiencing this before. I am aware that there are mods that are done as precautions... In fact, I have an old Bob Sharp prepared L-20B block that I have been hanging onto forever, and it has these: I don't have a handle yet on how much power my engine is putting out, but I wouldn't have thought this mod necessary. My front timing cover is modified for a Maxima diesel pump, but I am running a stock pump because I haven't been able to locate one. Don't see how this could be an issue... Anyone else have this happen to them? Engine seems fine, by the way. I think (and hope) that I caught it in time. Garrett

Regarding air restriction/air starvation: it is possible... but the inlet pipe, at 3", seems to be about as big as I have seen people use. The air filter on the inlet may be too small. Certainly can't rule it out as I haven't tested it in any way. Regarding fuel level inside the carb being too high: I have set the float level as best as I possibly can. I cut a strip of metal so it was between 12.0 and 12.5 mm in length (specification is per the Mikuni manual) and then used that to set the float height - making sure to check it against each float in the carb (2 per carb). Regarding air jet too small: I think that is possible too. See below. I agree with you about the full throttle in 5th at low RPM. I'm not sure what is going on, but since I had already tried several jet combinations and seen pretty much identical behavior for each under that scenario, I just wanted to try something radically leaner to see if I could make a noticeable change. No dice. So, I'm ditching that test. I wonder if it has anything to do with the lack of port velocity with that big cam and the low RPMs... not going to dwell on it. The thing about the pump jet is this... If I understand correctly, the hole settings on the pump rod adjust the volume of fuel. And the pump jet simply adjusts the hole size that this fixed volume can go through. A bigger hole translates directly to a shorter duration of time for the stream of fuel. So, whether I use a 35 pump jet or a 50 pump jet, if I leave the pump rod setting on the middle hole, with either, I get the same amount of fuel when I open the throttle. The difference is how fast that fuel gets discharged. So, if I put a bigger pump jet in with the same volume, it has to improve the lean condition - because more fuel is coming out over the same time period in which that lean condition existed previously with the smaller pump jet. The real question in my mind though is what are the bigger pump jet effects just after the lean spot. As you said, it may be dumping more fuel at that time as well and cause a richer condition at that point in time. We have a pretty good feel for when the pump jet starts squirting fuel (we can see the RPM's increase in response to throttle input) but no real good idea when it stops... If we could see both of those points on the graph, it would be easier to determine if a larger pump jet is going to add even more fuel on top of that rich spot that is occurring just after the lean spot. Here is another graph from tonight. I put back in what I had before: 180 mains, 220 airs, 57.5 pilots... and switched to the 50 pump jets: Judging by my graph above, I'd say it seems to have helped the lean spot a bit, but didn't really hurt the rich spot. The lean spot is still there, as is the rich spot, but the extremes seem to have been reduced. I'll do some more testing, but look especially at the second measurement that I have on the graph. I am in 3rd gear at about 4500 RPMs and I floor it. The lean jump is not that bad, and the rich spot afterwards is not bad either. But you can see the jump to lean, then rich elsewhere in the chart... The first measurement is where I double clutch downshift from 4th to 3rd... I blip the throttle to match revs (not high enough though), and there it is... lean then rich in a split second. You can also see it a bit when I shift out of third into fourth and lightly apply throttle afterwards. Also, from 6500 to 7k the AFR drops from 13.4 to 12.1... Not sure what that means, but as Lazeum says, maybe my air jet is too small. The results at this point are pretty good. The car will idle forever without loading up... AFR ranges from high 13's to low 15's depending on road inclination at cruise - with very little throttle. Going down hill for long periods of time with absolutely no throttle will send the AFR slowly upwards to high 16's, low 17's and it will start popping out of the exhaust a tad if I let it get that high. And with this jet configuration, the car is developing good power. It is certainly very driveable at this point. I'll probably move the rev limiter up to 7700 now and do some more testing. I'd like to address the quick lean/rich on abrupt throttle openings a bit more, and I am not convinced the mains and air are where they need to be yet, but I am getting there.

Cool. Thanks for offering... I just started doing some more testing and when I feel like I know what direction I need to go, I'll be in touch. Basically, what I have been doing is taking the car up on the highway and doing 2 pulls in 5th, 2 in 4th, and 2 in 3rd. With each, I start our 65 or so MPH. I had the car running pretty well with one combination, but the thing that is bugging me is the 5th gear pulls. Consistantly, shortly after giving full throttle, the AFR drops down... down and then, when it gets below 10, the motor starts acting up, so I immediately let off. So... to rich on the mains right? To see if I could alter this behavior in 5th specifically, I went with the leanest sets of jets I have on hand. 150 Mains and 190 Airs... along with the 57.5 Pilots and 40 Pumps. And here is what happened: Sooooo... how could that be? Mains too big? I think not - as here is a run through a couple of gears with moments of full throttle, but it was leaning out big time with this combo. This graph shows that pretty clearly. I have a run in 4th also, but I just stopped making runs with this combo because it is clearly too lean. I guess it is possible the air is too big, and the main could be sized correctly, but based on my results from this following combo, I don't think that is the problem: 180 Mains, 220 Air, 57.5 Pilots, 40 Pumps... these are the two 3rd gear runs: And, yes, I totally have a hesitation for a split second when I snap the throttle open. I'll try larger pumps... which should shorten the duration of the fuel stream event. The way I read these graphs, it seems that right at full open, the AFR jumps lean, but then is followed by a brief rich spot before it seems to come into a steady line. This can more readily be seen in this 4th gear run: Perhaps larger pumps will put more full into the first half and less into the second... and smooth it out. We'll see.

I'd like a set of the clear with polished aluminum rings. Looking forward to seeing the final installed fit, when you can. Oh, and isn't there a forum for group buys? I just happened to visit this forum for like the second time ever and saw this. I think you should post something about this in other forums as is appropriate so some more people will see it - if that is a good thing. G

Got the potentiometer from radio shack. They didn't have a 20k or 50k one, so I got 100k instead. Wired it up as instructed in the LM-2 manual, turned it all the way clockwise, and started the car. The LM-2 was reading 0 RPM's (as the manual indicated it would). I then slowly turned the potentiometer counter clockwise and "voila", RPM's are showing on the screen now - nice and constant... and changing with engine speed. I was going to go record a couple runs, but the transmission has been leaking and it seems to be getting worse. I'm not 100% positive, but I think it is leaking from the O-ring on the "striking rod". That is the main shifting shaft. There is also an oil seal in there. I rebuilt the transmission a couple of years ago, and definitely didn't replace those. So, I think I'll try to order those up and see if that fixes my leak.

Read some forums and found where people having same symptoms with AFR readings on their LM-2 fixed it by re-calibrating the o2 sensor. So, I pulled the sensor out of the exhaust pipe and took the unit outside the garage to another one of my cars (for power) and re-calibrated it. Then I re-installed it but it was too late at night to fire it up to see if the AFR readings had returned to normal. As I was trying to go to sleep, I recalled that I had seen "CAL" show up very briefly on the LM-2 screen. Thinking through the event... I believe I somehow triggered the calibration mode without going through the menus... and the thing calibrated while the engine was running. Again, E9 is "supply voltage too low", so when I first saw it, I reached in and pulled the power adapter from the cig lighter and put it back... and I did this a couple of times in rapid succession hoping to get a better good connection (I have since then gone through the cig lighter and cleaning everything for good electrical connection). I also read through the Crane Hi-6 manual and the LM-2 manual in search of answers for why the RPM's weren't being read correctly. I'm using a MSD tach adapter with my Hi-6, which I had to put into the loop to get the stock tach to work. Not sure, but I am guessing that wiring the tach adapter into the mix could be causing the signal the LM-2 is looking for to be unusable (the negative from the coil). So tonight, I took the LM-2's black and white wire which was hooked to the negative wire coming from the coil and changed it to the tach output wire on the Hi-6 (green wire). Seems logical that with so many people having good results with hooking that wire to the MSD 6AL tach outputs (more forums) that the LM-2 should be able to use the Hi-6 tach output signal. Then I fired it up. First, the AFR readings are back to normal. So, the O2 sensor isn't fried yet. The change I am seeing as a result of moving the RPM wire location is basically twofold. First, RPM's almost never read 0 now. Second, I get a few, somewhat accurate readings around idle speed, but when I get into the throttle at all, the RPM reading on the LM-2 screen jumps to various readings in the 1k to 5k range. They are pretty random. The LM-2 manual has a brief section on "Attenuating a Tach Signal" which involves putting a potentiometer into the circuit. I figure that is worth a try next. Progress can be painfully slow sometimes.

Until the learning stops... completely. Tonight, I again hooked up the black wire with white stripe from the analog cable to the negative on the coil (it is actually a Crane LX91)... I was watching the RPM's on the display of the LM-2 to see if there was any pattern to what it was displaying. I'd get all kinds of numbers but generally it would bounce from some random number like 240 to 540 and then to 0... then to 360... and 0. I was playing with the wire to move it around and see if that made a difference (which it didn't) but the longer it ran, the better it got. After a few minutes it was actually registering some rapid changes for short bursts of time like 850, 870, 840, 880, and when I revved it a touch it read 1100's, but then it would still revert back to 0 or 300 or 540 for brief periods of time. I got distracted for a minute or so doing something, and when I looked back at the meter, it wasn't displaying AFR any more. It said "E9". I turned the car off (because running it with the O2 sensor not working is bad) and pulled the cigarette adapter power cord out and plugged it back in again. Fired it up and AFR was again displaying but long story made very short, now the AFR is completely wacked... reading completely different readings than before and jumping absolutely all over the place. I think the 02 sensor is shot - thanks to me running it without power for too long. I took it for a drive to see if it would "clean up", but no luck. And the RPMs won't even begin to work at anything over 1100 RPM. As soon as I give it any throttle, they drop to 0 and stay there most of the time... or go to 10... or 30... but that is it. So... I'm pretty stuck at the moment with a non-functioning LM-2.

Looking forward to that day... in the meantime, the learning continues.