ckurtz2

Yes. So the companion flange female splines fit over the male splines just a little bit. But then I have to impact on the companion flange the rest of the way. After the companion flange is completely on I can notice it is all out of true. As when I spin the whole thing the companion flange looks all bent and no longer circular. In fact it actually made contact with the strut and I have to bend it a little back. I’m just thinking that because of this rhe axle must be bent at the area where the splines are. As the companion flange probably bends to fit the bent shaft. I hope this makes sense. I have no proof but this is my theory. The strut and races looked good before I put the stub axle in. I doubt they got messed up. But I did have the axle on a 80,000lb press. Probs messed it up there when putting on bearings or wheels studs

It is possible, but I don't think so. I am considering making a thread for it though, because I want to know how it would even bend in the first place or if something else is causing the companion flange to twist and bend. So bad that I have to use a big bearing puller and a breaker bar to pull it back off the splines. I just don't understand it. The driver side one works perfect and assembled perfect.

Looks like I will pull the shaft and see what happens with the shop. I pray it is this, however I put the car in neutral at about 80 and let the car coast and it still vibrated like hell so that's what has been steering me off that conclusion. Also yes, wheels were balanced, car aligned etc.

Hey Mark, I rebuilt the entire drivetrain and suspension components about a year ago. Just finally got the car back on the road. Anways, every single ujoint is brand new and solid. I checked the half shafts. I am going to pull the driveshaft and take it back to the shop it was rebuilt at to make sure it was properly balanced and rebuilt, I remember thinking one of the new ujoints was iffy. Anyways, The rebuilt stub Axle went smoothly into the car when I installed it. However, when I istalled the companion flange I had to impact the nut on to tighten it. When I did this the stub axle seated proper, but the companion flange would bend up. Went through two companion flanges and decided screw it cause I was so pissed off at the time. Anyways I am pretty confident the stub axle is bent due to this reason. I guess somehow I bent it on the press? Or the PO bent it and I didn't know. Vibration happens anywhere from 30mph all the way to 100+. I feel it is on a harmonic cycle, because it will disappear slightly at certain speeds under acceleration, but once I decelerate I am doomed. The vibration is really bad though. So I am assuming its either that most likely bent axle, or prop shaft like you mentioned. Lets hope its the latter, but I probably should fix the stub axle anyways.

View Advert 280z Stub Axle and Companion Flange Hey guys, I could really use some community help on this one. I need a stub axle and companion flange, because mine unfortunately is bent and is causing a pretty mean vibration while driving. I think I bent it when installing new bearings. It is the right side on a 1977 Datsun 280z coupe. Anyways I am on a tight budget so if anyone has some extras lying around I'd be happy to pay something for it. Advertiser ckurtz2 Date 09/06/2022 Price Category Parts Wanted Year 1977 Model 280z

Ok. What are the injectors you are running? On my car I had the old ones rebuilt by AUS injection. Turns out even the cleaned units were unbalanced and also still not flowing enough. They had the OEM late 280z green body and part numbers. So I would advise you pull the rail and do a volume test to see the flow rate. I had to buy completely new injectors from MotorMan on Ebay. Could the stock filter be restricted and thus the engine runs richer and it seems like your issue is fixed? Or, funny enough maybe you had a vacuum leak there and while replacing the filter and piping it was corrected. If you could, take a video of what the AFM is doing when running, revving. I am curious what it is doing with the cone setup. The cone filter and stock filter should make absolutely zero difference. Both are considered cold air intakes, and both flow well.

Here is a link to Z when it was in really poor shape. Kind of acts like yours. It also was running incredibly lean. I had rebuilt the whole thing and was super confident it was done right with all of my "checks". Well turns out it had several sneaky vacuum leaks, and the OEM rebuilt injectors were unbalanced/undersized even though they were cleaned. However, in order to find that out I went through every single diagnosis check in the EFI bible ignoring the simple things and making my life miserable. So I encourage you to go through the entire EFI bible, but don't just skip over something because you checked it once. Just my 2 cents. I also would go through every single forum related to your issue. Soak up every detail, the more you know the easier things are. Also drives you crazy though🙃 Here is some of the process I had to go through on my EFI system. As you can tell it was a mess. Don't be lame/lazy and swap to carbs, stock EFI is a good system. Do your RPMs bobble at idle?

Can't say I am an expert, but I just got my car running near perfect after about 2 years of woes like this. I learned the little things are super important. First things first, make absolutely sure that your car has no vacuum leaks like you mentioned. Trust me on this. Even if you think you got them all, triple check. Even the smallest vacuum leak can cause huge issues. Sounds like you smoke tested it though. Second, if your plugs are fouled I strongly encourage getting a brass brush and cleaning them with brakekleen. Plugs make a huge difference, and often times when you are dealing with a sick engine they can get fouled pretty quick, so while you are trying to fix the motor, make it a habit to pull the plugs to inspect/ or clean if necessary. Ok, now this is critical. Don't just have "cleaned" injectors. I learned the hard way that even if they are clean, the motor can still run like crap. Make sure that they are "flow matched" so that each cylinder combusts evenly. In my case, it made a huge difference on part throttle and idle response. I am assuming that you checked your EFI coolant temp sensor. Definitely run the resistance check on this, because it can be a problem. Make sure the TPS adjustment is good too. You seem competent enough to have done/ know how to do this. Make sure each cylinder is firing at idle. Pull each plug wire one by one and see if it is, there is always the chance that your problem could lie in one particular cylinder. Check timing, I know 10BTDC is what the manual calls for, but sometimes it likes just a little more. Also I agree that your FPR regulator seems to not be working right, at idle it should be much less than 36psi due to vacuum pulling on the diaphragm and limiting the flow. Now last look at the AFM as the culprit. Very Rarely, especially on a stock engine, is it considered bad. In my case this was the very last thing I fiddled with on my motor. It was a rebuilt unit from zcarsource, and the tension cog was ridiculously out of spec (waaay to loose). Now a backseat diagnosis that could be wrong so don't take my word for it. your AFR at idle should be around 13.6. Apparently the L engines like to be rich at idle. You can fine tune this with the AFM mixture screw once you find the real issue on why the car runs poorly. Next, it seems odd that when you give it throttle that the AFR is shooting all the way lean. It is possible (considering the black plugs) that the AFR is reading lean because the cylinders are running so rich the mixture is missing causing the AFR not to get a reading. In my opinion (because it happened to me) if it was running that lean when given throttle it would pop like a SOB out the intake. Yours just sounds like it's bogging/ missing. I also (with the same AFR setup) have seen numbers showing my car idling at the infinity mark. It turns out it was so rich my engine was missing considerably, and the AFR gauge couldn't get a proper reading. If it truly is running lean at throttle, then I would once again make sure there are no air leaks, fuel restrictions due to dirty gas tank etc. Read the EFI bible. Once you get a full understanding of how the system works you realize there could be dozens of possible reasons for your issue, but only a few plausible. The more info you provide the more we can help!

Clicking could be anything, most likely electrical like a relay. Where in the engine bay is it coming from? I am with @Zed Head it's fuel related. definitely see if you are getting fuel pressure. Maybe a simple way to see if you are getting any fuel is to pull the plugs after cranking and see if they are wet with gas.

Down in Arizona I have had several transmissions for different vehicles over the years rebuilt by a specialty shop called Hayes Transmission. Funny enough the only manual transmission fluid he swore by was an OEM KIA fluid. UM090-CH036. It is 75w-85. I run it in both my 4runner and 280z, and both transmissions work like butter. I would like to mention that the 4runners transmission was rebuilt and I put in MT90. The shifting was very choppy and drove this for about 6k miles. Finally listened to the tranny mechanic and the KIA fluid turned it to butter. Honestly though, most all GL4 manual transmission fluids should be fine in the proper weight.

Time to confuse everyone again. So all things aside. I think the cam is gonna be able to be dialed in for the stock EFI. I did a little bit of work with Chuck a few weeks back and I think it's going to be doable. I'll explain that when it's all dialed in, in the future. With the tweaks done to the car it no longer runs nearly as rich (still slightly), and it doesn't seem to lean out anymore at high rpm. So I am 100% (bold statement) positive that the issues I am dealing with now causing the car to run rough at low rpm are still in cylinder #1. Let me explain. So, cylinder #1 absolutely does not fire at idle. I bought a new spark plug(s) for it and let it run for about a minute cold. Pulled #1 plug and looked at it. Still looked completely new and noticed just a small amount of oily like film on it (can't confirm if it was coolant, oil, or gas. I don't have a great nose). Ok, so I installed the plug again and let it idle till warm. Pulled plug again and barely noticed a difference in the plug. Ok so I got in the drivers seat and in neutral held the car at 2000rpm and pretty much just revved the car between 2000-3000rpm. when accelerating I noticed that a thin cloud of white/grey smoke came out as well as smoke that was dark gray/black. I could distinctly see two different smoke colors. In addition, every once and a while it would pop out the exhaust. Ok, cool, confusing. What's new.. So I disconnected the injector connector to cylinder #1 and did the same test. No more popping, no more black smoke, and only a small small amount of that white smoke. So after alternating this test a few times I noticed that it would only pop and display black smoke after idling for a few minutes followed by revving with cylinder #1 connected. In addition, the white smoke was much stronger when cylinder one was connected. I never noticed the plug being covered in fuel, nor did I notice it becoming super black and carbon fouled. Looked rich, but not by much. Now, I pulled the #1 spark plug wire while the engine was idling and noticed no difference in rpm. I also pulled the plug wire at about 2700rpm and noticed no real change in rpm, but the exhaust did sound different. So I think it's firing, but not strongly, and only at higher rpms. I also swapped injector connectors again and #1 connector worked on #2. I looked inside #1 cylinder through the spark plug hole and noticed it looked much cleaner inside on the piston top compared to other cylinders which clearly showed signs of combustion. Now cylinder #1 shows 150psi or so on compression. I pulled #1 and #2 injectors and turned over the car. Both show decent spray patterns with what looked to be the same flow. Spark is totally good as without even pulling the plug I can get the wire boot if pressed against the valve cover to zap it. So I have spark, fuel, and compression at idle and no boom. If it is firing at idle it is extremely weak. What can possibly cause this. Oil does not look milky or low, coolant looks green, pretty clear, and not low.

This makes sense. Lol I just saw the external oiler knowing the cam was internally oiled and figured they were both putting in work. I stand corrected🙃

The second part connects at the lower differential mount. I have a photo before I did my suspension resto. It is supposed to have rubber or plastic covering the face of it. Don't ask me its purpose, I have zero clue haha.

@Jeff G 78 Just saw this. Well, thank you! Were u able to see if it was good? That's awesome, I love the sound of Ford V8s. The high revving gt350s make it all the better:)

Yes, my N47 originally had just the spray bar, interesting that it is considered rare for my car. Now I am running an internally oiled cam with the spray bar too. If the ZX cam would work I would love to put it to good use! Just set a price. I will see what this weekend brings about when it's at the shop if I end up throwing in the bag on the cam, or if a solution comes along. That video is badass, the car sounds so good. The track itself looks really fun too.

Yes, so the original cam is an option, but only because its cheaper than going to a new EFI system (I am ruling out Fast EFI cause it doesn't have that much tuneability). The entire reason I upgraded cams is because I messed up my cam oiler and it destroyed my original cam. The comp cam and original cam were around the same price when switching to an internal oiling cam so I chose the comp cam. So it isn't really readily available to swap to the original:( online looks like it would set me back several hundred dollars. Unless you guys know where to get a cheap one I really would rather not. Interesting Jeff. If I could go back in time and go the original cam I probably would now. That Shelby sounds sweet. Anyways, I know the power hunger haha. Long story short I drove a friends a Warrior 302 and stick shift hellcat a lot in highschool. Lots of fun, but almost too fast as to where I would get into "criminal" territory real quick.

@Captain Obvious I think it is gonna have to be some old school fun (not fun) haha. I just need it to run well enough to where it doesn't bobble at idle as much and can actually work at WOT so I can have some fun while not hurting the motor. Depending on how good it works, then I will either hold out on a new EFI stuff for a few years, or next semester. Time will tell I guess. Just having a really hard time wanting to dump even more money into this car when it still has a crabby interior and I haven't even been able to drive on public roads. I've also been considering just swapping back to the original cam, but I'd rather get this one to work.

Yeah, I think my problem is all in the cam now. Here's a little update. Cleaned up tons of grounds today, and replaced several connectors as well. Once warmed up it idles way better than a few days ago, but still not quite right. Shakes and you can hear a miss every once and a while out the exhaust. Took it for a test drive, and it felt the best it ever has. About at quarter throttle it pulls pretty nice, sounds like all 6 are firing, and feels smooth overall. All of the problems I have noticed are at idle or WOT. So I tested WOT a few different ways. I put it at WOT at around 2100 rpm, no stumbling and it would pull harder and harder until about 3100 rpm and then miss to all hell. I then started from around 2000 rpm to about 3600 rpm at a quarter throttle and it didn't seem to miss at all. I then tried WOT after getting it to around 3200 rpm using a quarter throttle, didn't like that.(Note: I don't want to try things higher in rpm, because the cam is still technically breaking in). Ok, cool. Figured this would happen. So I pulled plugs and yep all the ground electrodes are white as day and the outer edges of the plugs all have a little bit of black soot. So my visual diagnosis is rich at idle and waay lean under load and higher rpms. This will be the baseline, hopefully this issue will be able to be worked out with some tweaking. I also want to mention I had the potentiometer on and cranked about 1/4 of the way. Didn't want to toy with the AFM... not yet.

Lol, love to see the discussion, nice to learn something new:) Replaced plugs (gapped to 0.04), cylinder 5 came back to life. Ran waaay better, but it would still surge a little bit and miss. So I think that my whole electrical problem was fixed. Ended up being a loose plug at the dropping resistor, and spark plugs. Go figure, sometimes the most complicated of issues are quite simple. The new plugs are starting to already carbon foul again. So my plan is to replace the connections at the WT sensor. The vacuum sits at around 15.5hg so I think having it vacuum tested will be a very smart thing to do. And if it doesn't climb to something better, than another solution will have to be figured out. I think the main reason those plugs are fouling is due to the fuel pressure being too high (low vacuum means the fuel pressure climbs significantly:(. Maybe an interesting solution will be a fuel rail with a different fuel pressure regulator. Who knows at this point, time will tell.

Lets settle this. The Number is E12-12A. 7112

@S30Driver So the transistor ignition unit is what was upgraded and the ballast resistor has nothing to do with it? If that's the cause I will definitely change the plug gap then.

Interesting, I feel like Datsun jipped me on the ignition system then haha. The vin plate says 01/1977 so it is an early 77. Also has the weird sloped rear deck. Here is the ballast resistor. Well I got the BPR6ES so it's pre-gapped to .035. I can almost guarantee that I left that gap on the old plugs which were also the same type. What gap would you recommend then if I am running the weaker type system? Just do like 0.04?

Yes, I have a ballast resistor. I tested it last year, and it looks like it is still in good condition.

Ok, just got new plugs. I will install them before the car goes to the shop as well. Interesting, I am looking into it:) Does the GM HEI or Petronix HEI modules really make that much of a difference in the strength and consistency of the spark? Trying to save some dollars and cents. Yes, I am still running the stock dizzy with the transistor ignition module inside the car as well.

To answer everyone's questions @Jeff G 78 My vacuum reading at idle when cold is around 11hg which is terrible, and when warmed up it climbs to around 15.5hg. Still below what it should be with that cam and well below stock numbers. Yeah, there are two resistors, and both cylinder 1 and cylinder 5 are on different ones, so I am confused as well. It could have been mere coincidence, but I am not quite sure. It will all be looked at this weekend. I will make sure to do spark plugs again then. would you recommend cleaning them, or just new ones. @Zed Head yes it is still the stock ignition system with a petronix flame thrower coil and rebuilt distributor. What would you recommend?