Pac_Man

Cracked heads aren't entirely unheard of. Was the head gasket recently replaced? And if it was did you inspect the bottom of the head for flatness?

A lot of what I've done recently in the time I've had has been cleaning things up and putting the car back together. I put wiring cover stuff over pretty much everything new that I added. Fuel pump is all wired up with a relay and I found a different spot for the boost/AFR gauge which will hopefully be secure enough and out of the way. ECU is mounted so the harness is out of the way of my feet. Wiring is tucked up out of the way and exposed wires have been covered with liquid tape. Passenger seat and glove box are back in. One of my AN fittings for the loop on the oil cooler block attachment was leaking so I decided to just buckle down and make the new lines to go to the oil cooler. The idea of all that air being in the oil system didn't settle well with me so I unhooked both lines and used an old turkey baster to pour oil into one fitting held above the cooler while the air purged from the other fitting. Added a little extra as well to compensate. Fixed a pretty significant oil leak with the bonus of getting my oil cooler hooked up which will make me feel a lot better about preserving the life of my oil cooled turbo. Right now the main issue on my plate is that the car seems to want to die once it starts to warm up. Not sure if it's because I haven't gotten my timing dialed in or an electrical issue. I've done some research but most of what I find pertains to NA cars and involves ignition modules or vacuum advance. I'm suspicious of the CHTS since I never changed it, so I'll have to do some resistance testing and see what that gets me.

When I get the cash to do an overhaul of my suspension, this is pretty much the sole reason why I want to get T3 rear control arms.

Dave Irwin rebuilds them as well. Not sure if he's on here but you can find him on Facebook. He is a well-known Z electronics guy and supplies the headlight relay kits to MSA.

For the record, JIS is the same as BSPT.

RB 25/26/30 flywheel is 240mm and effectively the same as the 2+2 S30/S130 and turbo S130. I think it has a locating dowel hole or something which you wouldn't need to worry about obviously. I want to say the RB20 has a 225mm flywheel but it's been a while since I researched it. KA24 flywheels are also 225mm if memory serves correctly.

A bit of a selfish question but I'm curious since you mentioned the LSD setup using a 300zx diff and J30 center housing. I have what I'm fairly certain is a Z31 VLSD with a welded center section, so it's effectively useless in that sense. Does the J30 differential use a longer axle like the Z31 VLSD? This diff will accept the stock stub axle from my 280z on one side but it won't clip in on the other side. That's what made me pretty much certain it's a VLSD.

I'm sure people would be interested, but I have seen a lot of good ideas where people are interested but they never get off the ground when it comes to people actually putting their money down on the table for it. Definitely interested to see if this turns into something, though.

They've been working on a website overhaul, but things are more or less functional now. A lot of the old links don't work and the sites have been merged into a more modular design that incorporates what used to be multiple individual websites. I think this is the page you're looking for: http://www.xenonzcar.com/s30/heads.html

Hi cgsheen, I did unbolt the fuse panel and looked at the back. Nothing unusual there. After reviewing a diagram I have, power going to the fuse block passes through the ignition relay before continuing to the fuse panel. Unless this diagram I have is incorrect, I concluded that is the reason why I was not getting voltage to that wire as the relay is disconnected. I had absolutely no issues before and the only changes I made were removing the old EFI harness and disconnecting most of the ignition harness. I hooked up a temporary connection to a known 12v switched source and everything works normally with that.

Over the course of a few days I've been working on the differential. I had been experiencing some noise on deceleration around 45mph and it looked like the axle seals were a bit wet from oil weeping. I decided to pull the diff and service it just to be on the safe side, as the last thing I'd want is for the diff to run low on oil and lock up on the freeway and ruin everything else with it. Long story short, did a lot of wrestling with the rear end of the car and dropped the diff out. Drained it, ordered and replaced the axle seals, scraped off the old cover gasket and replaced it with permatex ultra black. Let it cure and then torqued it down. Then refilled it with GL5 80w-90 gear oil. I noticed some clearance issues between the control arms and the stub axles in the diff when dropping it so I waited until it was bolted back up to place them back in. Pretty easy with the wheels off and a long enough piece of pipe, just a couple good smacks with a hammer and they seated themselves. Getting the half shafts back in was tricky so I left the bolts holding the control arms a bit loose to give me a little more room to play with. After that I bolted the driveshaft back up followed by the sway bar. The car is finally back on four wheels with fresh fluids all around. This marks a huge job off of my list of things to do, but I still have a few more things before it's ready to be driven: Hook up 12v switched to the fuse box for the gauges Finalize the fuel pump wiring Clean up the wiring with wiring harness sleeve and liquid electrical tape as needed Bleed the clutch slave cylinder Drop and align the oil pump shaft Final torque down of motor mounts Have downpipe and wastegate dump tube modified so I can at least drive it to the exhaust shop

Looking over a wiring diagram, the coil seems to be fed 12v via the ignition switch. According to the diagram there is a green/white wire going from the switch to the tach, then continues out the tach as a black and white wire which leads to the coil. I suppose you could hook up a wire from a known 12v switched source to the coil and see if that works. Assuming the coil is grounded, there's nothing based on the wiring diagram that would make me think it could cause issues.

Assuming the "E" post is what you're saying is missing, then that would mean the alternator is not grounded which would definitely cause issues.

Well, I've been an official college graduate for coming on two weeks now and I hadn't touched my car. I decided to change that today. The main issue I wanted to check was my charging system. I noticed that the charging light wasn't on with the key in the on position and the engine off, so I knew something was wrong. I pulled the gauge and inspected the bulb; the filament was intact and there was continuity from the prongs on the side to the base, so I knew that wasn't my issue. Next I checked for voltage at the connector and there was none, which if memory serves means that the charge light should be on [citation needed]. I went inside to check the FSM and wiring diagram and found that one wire feeds voltage to the tach, oil/water gauge, and the volt/fuel gauge. From previous endeavors I knew that the tach and oil/water gauge wire was not getting voltage from the fuse panel, so I knew that the fuse panel must not be getting voltage from the source wire. I didn't delve fully into figuring out why, but I think it's tied into either the old ignition/EFI relay or the Ignition Control Module- both of which have been disconnected. I cut the wire at the back of the fuse panel and spliced it into a known 12v switched source just to test it. Went to start the car but forgot to hit the fuel pump switch, however I saw that the tachometer was bouncing while cranking! I turned on the fuel pump, started the car, and my tach, oil/water, and voltmeter gauges all work now and the charging circuit is functioning normally! Maybe a small victory, but I've really been struggling to find the motivation to work on my car recently. I've got a list of what needs to be done, and I'm going to start working through it. I also did the final torquing of the crank pulley bolt today, so I guess that's another thing to cross off the list. Allons-y!

I threw an L28ET from an '83 280zx into my car and the intake manifold had the linkage piece on it but I didn't have anything else. I used the stock linkage on my car up to the part that hooks onto the manifold piece and it worked great aside from working backwards. The gas pedal sank and I had to pull it up toward me to open the throttle. Flipping the hooked part 180* (upside-down from normal) made it work fine.

Oh I know it isn't just a direct bolt-in, but I know that it's a common swap with a lot of information on it. I'm confident that I could do it easily. As for the BE section of the FSM, I didn't really find anything in there. I have an understanding of how the gauges read, it's just that I'm almost certain they aren't getting power. The fuses for the gauges get fed 12v+ switched power from the ignition switch in the On/Start positions so I guess my first step is to check and see if the fuse box wire gets voltage when the key is turned to On.

Hi everyone, I've been getting some advice in the build thread I've got going but figured this would be the better place to chase after the issues I'm having since it's more technical and a better setting to get pointers of what to look for. So the background: 1976 280z with an 11/75 build date if it matters. Effectively stock, save for a few minor things and an L28ET. A couple issues that are electrical-related: 1) The system does not seem to be charging. Charge light was off with the car running. I ran the engine for a bit and noticed the fuel pump kept getting louder and the engine running rougher so I turned it off and found that the battery read ~11.3 volts. Checked the wiring at the alternator and it checked out so I started the car again and tested voltage at the battery and the alternator positive post. Both read ~11.3 volts. Had the alternator and battery both tested at O'reilly on their machine and it said it checks out, though I know that isn't a final judgement on whether or not an alternator is really working properly or not. By that point I had assumed it was the voltage regulator. Replacements aren't easy to get and they're either expensive or the shipping costs more than the unit. By the time that would all be said and done I figured I would be better off buying an internally regulated 280zx alternator. The alternator is a reman. unit from O'reilly that was on the old engine before without issue. Is there something else I could be missing here? I got a longer bolt/screw for the "E"/ground post of the alternator since the old one couldn't hold the wire and the capacitor at the same time. Is there some chance that the one I used isn't allowing the alternator to get a proper ground? I've also read things about how if the battery isn't charged enough the alternator won't charge, but I doubt that was the case since it seemed that the battery was at good voltage but gradually draining. I'm tempted to pull the trigger on a new internally regulated alternator and throw it in, but I would rather have someone point out what I can't seem to see is wrong before I spend the money on it. 2) The tachometer and oil/water gauge are not working. I know I have oil pressure as I verified that before starting the engine. The sending unit is new and I know it's getting oil. The stock tachometer coil signal wire is hooked up and I verified it at the resistor under the passenger side of the dash. Also verified continuity and resistance in the resistor. As far as I can tell, the gauges are getting the signal, they just aren't being powered. The lights do come on but after reviewing the wiring diagram those seem to be on a separate circuit anyway. According to another forum member, the 4th fuse down on the left side of the fuse panel provides voltage to the gauges. The fuse is fine and has continuity, though I don't get voltage on either side of the fuse. After checking where the fuse gets power from, it seems to be hooked into switched voltage from a black and white wire that is spliced in at multiple points throughout the car. Here's where it gets interesting, though. The fuse that provides power to the voltage/fuel gauge also appears to be fed by that wire, and I know my voltage/fuel gauge is working. I feel like I'm going crazy trying to track down the cause of the issue since every lead (no pun intended) I find ends up in me thinking that it should be working fine. Any advice is appreciated as always. Like I always say, HybridZ is the place I turn to when all my efforts seem to be getting me nowhere. - Pac Man

Like NewZed said, it would take some fabrication. A lot, really. Techno Toy Tuning offers a kit that will let you swap in the diff of your choice, but it certainly isn't cheap. As far as the effectiveness of a VLSD, I have seen a lot of complaints that they don't lock very well. If you're going with a diff swap, especially if it involves buying the T3 kit, I would definitely go for something that will perform to your expectations.

Check the rubber lines at the fuel pump as well and make sure they aren't kinked.

I had an issue similar to this when my fuel pump was going bad, except kind of the opposite order. It started doing it once every couple weeks on the freeway for a few seconds and then eventually it wouldn't run for more than a few minutes without it crapping out on me. Since it sounds like you have some gas tank rust issues, I would suggest draining the gas tank and dropping it out to take a look at it, or at least looking in with a flashlight. It's a well-documented problem with these cars.

Yes, it's a slow process since I'm in my final two weeks of university. Once I'm done I'll have a lot more time to get things finalized. I'll just keep the setup normal and keep an eye on my boost gauge. Head was checked but not rebuilt. Just changed the valve seals. I've seen the same issues, but luckily I don't have to worry about it.

Guess it was force of habit from my last job. Like I said, he has done these swaps plenty of times and is very familiar with the engines. He does swaps, tuning, all kinds of stuff. He's an older guy who has been doing this for years. Don't let my use of the word tech distract you from the other info, I wouldn't listen to him if I didn't know he knows what he's doing. Crank was shaved down .010" and bearings were appropriately replaced. Cylinders were honed and new pistons and rings were installed. Everything else was checked and of course gaskets and such were replaced. I suppose "romp on it" was more aggressive wording than I was going for. And putting a filter on the charge pipe would be difficult as I'm using the stock J pipe... I'd have to think about that one.

What would the difference really be? With what I was thinking of, the turbo would not really see boost in the first place. With what you're suggesting, the turbo wouldn't build boost since the air would just be blowing out into the atmosphere instead of being compressed in the intake and cylinders. And I made sure I had oil pressure before starting the car. It seems like there are two schools of thought for breaking in engines- treat it gently for a couple thousand miles or romp on it like you would normally. The most important thing seems to be using compression braking to push the rings out and seat them properly against the cylinders. This could be achieved without driving it hard but when I asked a tech (who has done these swaps plenty of times and is very familiar with Nissan's L series engines), he said get it on the road and put a load on it as soon as possible to break it in. This is what I had already planned on doing when I talked to him. I tried that as you were the one who informed me of it in a separate post I made regarding some wiring confusion. I'll double check my wiring but with that setup I wasn't getting voltage from the relay.

Life has been pretty crazy with school, taking 4 classes in one quarter is killer sometimes! I ran into more issues, specifically the transmission mount and the driveshaft. I wanted to get the transmission mounted and bolted before finalizing my measurement for the driveshaft. Through my research I found a post saying that the T5 is 30mm longer than a normal L28 and Nissan transmission. I had a transmission crossmember from a 280zx with the curve in it. That curve places the transmission mount 15mm back, which left me with needing another 15mm. I had heard stuff like "I notched it" and "this guy used a differential mount" but the only thing that made sense to me was modifying the mount. I was recommended a fabrication guy who works out of his garage and does primarily old hot rod stuff. He cut the center part of the transmission crossmember and moved it back 15mm (0.59"). I took it home, spray painted it, installed it, and it fits! So for anyone's future reference, the T5 sits back 30mm. The curved crossmember gives you 15mm, so just cut it and reweld it another 15mm back and you're golden. I forgot to take a picture out of the car so I snapped one of it installed: Next up was the driveshaft. I'm not sure if I mentioned it earlier in the thread but I went with the route that was recommended to me of having one built. Others have used Powertrain Industries in California with good things to say so I went with them as well. For anyone interested in having one built by them, the part numbers used were: Slip yoke: 1203-26S Differential flange: 1202-39 This is a setup for the slip yoke of the Nissan/BW non world class T5 found in the 280zx turbo and the differential flange of my stock 280z r200. My measurement for the driveshaft from the face of the transmission output seal to the face of the differential pinion flange was 26 1/8". I make no guarantees on the accuracy of that measurement for your purposes. This is with the L28ET motor mounts if it makes a difference, though I've heard they're the same. After installing the driveshaft, I reinstalled the rear sway bar with the new end links. Needless to say this was a big step toward having this car finally back on the road. I still have some kinks to work out. My gauges still aren't working and I'm not entirely sure why. I'm suspicious of my alternator not charging the battery even though I don't think the charge light comes on. I still can't figure out why my tach and oil/water gauge do not work, though I'm curious if the alternator has any effect on that. I also need to reclock the distributor/oil pump drive shaft. The ECU fuel pump wiring setup I have doesn't seem to work either. Worst case scenario I guess I'd just wire it hot since I already have a killswitch installed. Once those issues are taken care of she will be ready to get back on the streets. I think for breaking in the engine I'm going to run it for a while with just a screamer pipe where the wastegate would normally go to prevent building boost pressure. I know it will be loud but then I won't have to worry about building boost while breaking it in.

Zentech I sent you a PM.