NewZed

Aren't you screwed right now? You'll be in the same state, but at least you'll have tried something. http://www.carpartsmanual.com/datsun/Z-1969-1978/engine-240z-260z/engine-mounting/manual-from-c-hls30-46001-rls30-grls30

So, basically you're saying that you have a freshly built engine that has not been broken in. The main worry then would be the camshaft lobes and rocker arms. Zinc (ZDDP) seems to be key. There are a variety of break-in oils out there. VR1 racing oil seems to be popular, as one, for example. Not designated as a break-in oil but it's an older ZDDP containing formulation. People have had issues with using a non-zinc oil with added ZDDP break-in additive. Probably best to find a zinc-containing break-in oil. Brad Penn is a brand that seems popular. http://www.valvoline.com/our-products/motor-oil/vr1-racing-oil https://www.summitracing.com/parts/bpo-009-7120 http://www.competitionproducts.com/Brad-Penn-PENN-GRADE-1-Break-In-Oil-30W-Quart/productinfo/BPO30WTQT/#.V42S89IrKig Read up on failed camshaft swaps and you'll find many opinions but getting an oil with the ZDDP already formulated in seems like a good idea.

Your second video here is where it would have been informative if you could have had somebody press the brake pedal while the engine was running. You had video of the pinion shaft moving and the halfshafts. Pressing the brake pedal would have stopped the wheel flanges. Then things would have been clear, either both halfsahfts would have stopped and the pinion shaft kept spinning or only one of the halfshafts would have stopped.. The advice to remove the diff was a little premature, you were right on the edge of getting some good information..

Here's the original - http://forums.hybridz.org/topic/5380-broken-stub-axle-danger/

Here's another from a guy who broke his just tightening the nut. http://www.classiczcars.com/forums/topic/42487-rear-stub-axle-just-broke-when-tried-to-torque-nut/

Nice. Here's a link on how the 240Z's break their axles. It's titled "STUB AXLE FAILURE". About halfway down the first page here - http://forums.hybridz.org/topic/49194-differential-cv-lsd-hp-torque-r160-r180-r200-r230-diff-mount/

Here's a thought, that might be feasible - you have a broken stub axle in a wheel hub.The bearings will hold the wheel on, sitting in the garage. See if you can turn the wheel companion flanges at the hubs, without the wheel turning. This would let all of the things you've seen happen, without the car moving. It would be like lifting one wheel in a corner. The diffs need both wheels to have some resistance to motion for the diff to work right.

This is a very strange thread. You're not using some sort of odd two-piece splined driveshaft are you? You had a video of the transmission end of the driveshaft but not the pinion flange end. It's still not clear that the pinion shaft of the diff will turn without at least one of the stub axles turning. You have something missing in all of your descriptions and videos, either the wheels are up or the video doesn't show the right parts. If you could clamp the two stub axles in a large vise and use a wrench on the pinion flange you'd be able to tell if the diff is broken. If the diff is broken you should be able to turn the pinion shaft more than you described. "the pinion gear was turning for a brief period". You found a piece of a clip inside? Take some pictures. Down the spider gear holes and from the back. Bright lights, in focus. Take a video from the back with the cover off as you turn the pinion shaft. Lock the stub shafts down somehow and use a wrench to turn the pinion shaft. Something must be broken but it will take someone familiar with broken diffs to know. This should be a simple thing to figure out. Don't make it complicated. Your sig says "LS1" but your video shows an L6.

I think that your clutch is either slipping or stuck in the disengaged position. It's the link between your engine and transmission. With the car on stands there's enough drag to turn the driveshaft and wheels. With the wheels stopped by the ground,it slips. Check your clutch fork first to see if it's stuck pressed backward. If the clutch is jammed open though, the clutch pedal will require very little pressure to move. The slave cylinder rod will be extended. If it's not the clutch, then it's the transmission. Nice sounding engine. Must be a bummer to have it stuck in the garage.

Are the halfshafts still disconnected? If the car is up on stands, put the stub axles back in and put the transmission in gear. Crawl underneath, grab both stub axle flanges at the same time and see if you can turn them the same direction. It's sounding like you will be able to turn them and you have a problem with the splines or your spider gears. You may have broken somehtng when you were trying to pound the old twisted shafts in. The problem you're having in this thread is that you're reporting two contradictory things at the same time. You say the wheels turn when they're up, but they don't turn when they're loaded, on the ground. But you haven't confirmed that the driveshaft is turning when the wheels aren't. That's the key to knowing where to look. Is the main, center, driveshaft turning when the wheels (stub axles) aren't?

Grammar? You only have three topics and they're all unlocked. Must be someone else's thread.

They being ..... what? The stub axles or all three? You didn't say if the parking brake was on while it was on the stands. That would lock the wheels. You're trying to determine if the axles are mechanically attached, via the splines, to the spider gears. It's not clear what didn't turn while the car was on the ground. You said "they" instead of actually using the words. The wheels could turn just from viscous drag of the gear lube, that's why you need to lock the wheels with the parking brake. Look inside the diff holes and see the splines. They interlock with the splines on your new axles. The clips just stop the axles from sliding back out fo the hole. http://mech.sharif.ir/~durali/design/Shafting/details/Lecture%2020.pdf http://www.4x4abc.com/4WD101/diff.html

The driveshaft turns but neither wheel does? You're sure the stub axles are not turning? You didn't do something weird like forget to put the halfshaft flange bolts in? You can put the stub axles in the wrong sides but I think that just turns the LSD in to an open in the worst case, like with a VLSD. Not sure what it would do to the Subie CLSD. You have an odd problem if the main pinion shaft of the diff (connected to the driveshaft aka propeller shaft) turns but neither output shaft (stub axle) does. Could be that the splined section of your axles is too small and they're actually stuck in the diff by the seal area. I'm just making a WAG. Pull the axles and confirm that the inner splines turn is the next option.

What did you read? No use suggesting things you've already looked at.

Put it back on the jack stands, put the transmission in neutral, apply the parking brake, crawl underneath, grab the driveshaft and turn it. Does the drivehaft turn freely? If not, the problems on the front end, not the part you just worked on. Or just watch the driveshaft while you have it in gear with the engine running. If it's turning, the problems in the back, if it's not it's up front.

Should have put your "real question" in the title. Your car is not super low now and you want the same stance. So regular springs should put you in the middle of the coilover adjustment range. "Super low" means slammed.

I found some images of Nissan versus aftermarket lash pads and see that Nissan cut grooves inside the seat area for the tip. Aftermarket is flat. So the groove is just "normal" wear. Still kind of wondering how the rockers got on the engine. Is it a Rebello engine? He recommended used Nissan but went with reground used Nissan. Just seems inconsistent. Didn't offer to repair their error either. He's seen it before so knows about it. Seems like they should have owned it. Anyway, good luck with it.

Looks like the Paraut symbol. I just picked this image off the interweb. Paraut was/is, apparently, an indirect OEM for Nissan. Paraut/Atsugi/Nissan, something like that. http://www.elautoparts.com/item.wws?sku=A4040-51981&itempk=86615&mfr=Paraut&weight=0.20 The wear on the other end of the arm is interesting. Isn't the tip supposed to fit inside the lash pad? Shouldn't it be worn across the full face? Looks like it's sitting on top of something else and it's worn a groove.

Post #11 here has an interesting picture of a way to directly address the load transfer problem (I think it's from JMortensen's Diff thread). More discussion also, can't agree with all of it, about what is strong and what is levered. Not sure how the guy's two piece mount came out in the end. Notice that the thread's from 2006. Ten years of development work on the short nose problem. http://forums.hybridz.org/topic/50794-my-q45-diff-mount/

Here's a not-too-old thread with many of the same actors commenting on the same general topic. Started on page 4 with SUNNY Z's pictures, but there's 19 pages total, plus a vendor's forum or group buy thread out there somewhere . http://forums.hybridz.org/topic/117668-the-ultimate-irs-swap-for-s30s/page-4

You misunderstood me in the first example - the arm is the nose. Or the nose is the arm...the lever arm. That's the thing about levers, you have to pick the right side, for reference. I thought I was clear which side I was talking about, but may have left out a few words. I talked about both sides, separately. Another way to consider it is that the assembly has what is essentially a hinge in the middle, of what should be a rigid beam. Which is what one the Q45 guys saw in his mount. Hinging where the nose met the mount, nothing above it to stop the motion. The cradle idea is great for the short-nose R200 and Q45, because they have nowhere to mount anything. I like the nose extension because it allows you to leave the car alone. Make the diff look like a long nose and use the long nose mounts. Arizona Z Car used the LCA arms as the cradle. Anyway, Oz Boy is probably working up some new thoughts It'll be interesting to see where he ends up. The first draft looks well-made, but may just not be right for the application. Probably work awesomely with my 150 HP (what they say) L6.

I had it right, I believe. The mount or body is essentially trying to hold the nose of the diff down. If the nose is long, it's easier to hold down. Just like trying to stop a spinning wheel by grabbing the spokes near the hub or out by the tire. Much easier out by the tire. The body and mount is trying to stop the diff from spinning. The longer lever arm of the new mount also puts more load on those two small bolts in to the body. Not only more load, but more of a twisting, unequal load. As the nose of the diff pushes up on the new longer lever arm of the mount it either pivots around the back bolt levering down on the front bolt, or you can think of the front bolt as the fulcrum levering up on the back bolt. Pretty sure people have had those bolts tear out or twist the metal (I wrote this on impulse from the first few sentences, I see that you've addressed the weakness of the sheet metal). SUNNY Z maybe. The original design pulls up on both bolts but with a longer diff nose applying less load. These short nose designs all kind of introduce two new weaknesses. No offense, the work looks great. The end result is just weaker than the original design, to be used with a much stronger engine. More power through a weaker mount. I've though about just building a steel framework that "adds" a long nose to a short nose . Basically converts it to a long nose. The new "nose" would need to be stiff and strong. Then a person could use the original long-nose mount area, both top and bottom (the crossmember). This GM diff might be amenable to that because it has four mounting holes. The Q45's don't have the structure to do it easily, they're round and smooth. I feel bad criticizing hard work. Everyone has been stuck trying to work with those four small holes.

A little more help - the air space under the valve cover is the same air space that that breather tube connects to. The rocker area and the crankcase are the same space. If you're going to seal the bottom you need to seal the top also. Or just seal the intake manifold (where the PCV valve is and where that big tube ends up). You have a bunch of different problems to work on. Your 12% over-rate injectors are probably making up for the extra air. When you seal up the vacuum leak that you're working on, you'll have cut off that extra air. With no idle speed control the engine probably won't idle anymore. And you'll be running rich becuase the injector rates are higher.

It's been noted over the years by several, how the bushings allow the rear wheels to move forward in the wheel well. As the LCA bushings compress. There's pictures out there. Many people have problems when they install a short nose diff behind a high torque engine. There are threads out there about the Q45 diff, and the short nose R200. Maybe the R230 also. Leverage is the key. The shorter the lever arm, the harder it is for the mount to hold it down.

Follow the arrows.