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It is a R180 fitted with a Nismo LSD and 4.11:1 r&p. I acquired a pair of diff stubs from an early 80's R180A. It's found in the front end of the Datsun 4x4 trucks. This stub is a bolt-in and has the 6 bolt pattern (280ZXT). In my case, I still needed to make an adapter to fit the 930 CV. If you're running the 280ZXT CV axle then it's a perfect match. This stub could be adapted to fit most any CV. It could also be machined to be a snap-in. It's to the left of the diff in this picture.http://album.hybridz.org/showphoto.php?photo=5284&cat=500&ppuser=11402

Well now, I did some quick reading. It appears the 280ZXT can be made to fit with halfshaft mods. The 300ZXT would not be that case. The guts must be reversed to allow adequate clearance from the stub axle nipple/nut. That's a small price to pay for a stouter stub axle.

The companion flange I'm having made eliminates the 4 bolt flange. It will slip onto the stub axle and be held by the 22mm nut. The 930 CV joint bolts straight to it. It is 2.75" thick and 4.5" in diameter. The main concern now is finding a broaching operation that will work with me. Most of these are found in the north like VM Broaching in Chicago. The stock S30 companion flange can be reproduced if anyone wants to use the early u-jointed halfshafts. I have a few here to get measurements from. The 22mm nut should still fit too. The early halfshaft would be bolted directly to the new solid flange (no nuts, just bolts) the way I figure it. What I'd like to do is produce the 280ZXT and 300ZXT flanges slightly shorter to allow for straight installation of those halfshafts. I don't know if that is viable or not. Ross makes those billet flanges but I haven't done much research to see if reversing the CV innards is mandated for fitment. Seems he would have found a better way if it exist.

The first prototypes went back to the manufacturer as scrap. They are producing two new sets of axles with the proper dimensions. These still have a 1.245" -29 spline and the nut is being bumped up to 22mm. I should receive them early next week. The prototype companion flanges (for my Porsche 930 CV setup) are in a local machine shop. Once these are done they will need to be farmed out for broaching. I need some assistance at this point. Several of you are using different CV axles for your S30. I need one each of the 280ZXT and 300ZXT companion flange to take measurements from. I will gladly return these to the rightful owners once I have the info I need. Any offers to help?

The knocking could be from the diff nose lifting during acceleration. It could also be from worn out bushings in the mustache bar. Neither can easily be discerned from a visual check. Play in the stub axles is common on the early diffs.

I'd chose a Toy damper over the ATI or BHJ for price alone. A speedi-sleeve might make up the OD difference or another oil seal with a smaller ID. I need a reasonably priced serpentine drive for my SC project. It should work fine for most applications IMHO.

I'm find myself too quick to find fault when something doesn't go my way before I know all of the reasons and truths. Sometimes I'm right and other times wrong. That said, what a horrible set of circumstances. It is difficult to imagine what that fellow and his family are living through. I think it would be proper to pass along the best wishes for recovery from all of us here in the Z community to the husband and a post at the thread where the photos came from.

It appears to be a standard 5 speed. There's no cast ear off the passenger side just ahead of the outout. I'm assuming there is one on the drivers side that we can't see. That would indicate it is a late 70's or early 80's box. Brass syncros would not be found in a comp box to my understanding. My early roadster 5 speed does have the split steel syncros. What it came out of is uncertain. That might explain the gearing differences.

I saw one bolted to a BBC and stuffed into a 911 years ago. It seemed to be holding up well to high torque.

My first yellow top lasted about three years. The following two yellow and two red tops (land rover - has battery disconnect & Z - only has a clock, both seldom driven) have died repeatedly after one year. It's ridiculous at these prices! I'm going to something else...period.

Why not slap the Lexus transmission behind it? It would likely be the most cost effective choice.

I pulled a set of these wheels from a 72 240Z parts car. A web search turned up nothing. Anyone ever seen these before? They're made in Japan by Texas, named Bridgestone, and are marked 6-JJx14 15. That makes them 14x6 with a 15 mm offset the best I can figure. The center hole is 3". I think the first 300ZX center caps will snap right in. These weigh 14.5 lbs a piece. They remind me of Crager Thrust wheels. The five spoke is a nice touch. There is minor curb rash. It could be repaired or just polished to clean it up. I have no use for them as I'm converting to 5 lug wheels. So, what does anyone think they might be worth on the open market?

I'm finalizing a new drawing for the 19mm offset stub axle. Having looked at larger nuts I'm leaning towards the 22mm 1.5 size. The reason is twofold. One, a 2mm diameter jump is actually quite substantial. It also allows companion flanges to be machined for those using the early 4 bolt U-joint halfshaft as well as larger flange bolt patterns. This should help reduce the number of different stub axles and companion flanges needed to cover a wide array of applications. Secondly, I think the failure at the thread/spline area is caused by over-torquing and/or stretch when the splines start to deform (twist). The larger spline area should eliminate the second issue entirely.

I believe your limitations are 86mm without sleeving. I'm waiting on sonic testing for my LD28 block before custom pistons are selected and ordered. Sleeving was a consideration for me too. Once I realized that the sleeves alone would run about $100 a piece, plus the machining cost involved, I decided a 2.8 to 3.0 would serve my purposes well. In the long run, I'd be dollars ahead just dropping in the LS1 sitting in my garage.

Can someone mic a Z31 stub axle for me. I need to know the diameter of the threaded portion for the nut. Thanks ahead of time.

Well, I have considered this. I persomally feel this failure point is directly related to overtorquing the lock nut. The only force applied here is the clamping force. Even in a high speed turn the side loads imposed should be lower than that required to snap the axle here. Since I need to have the axles machined again I will look into a larger nut too. Any suggestions here?

I'm glad to see the response. Now for a reality check. The machinist screwed up. It's easily resolved but does present a minor setback. I provided drawings and a stock axle. I requested the identical axle dimensions (as far as bearing spacing,etc.) but with the flange pushed 3/4" more outboard. What he did was machine a stock axle with a 3/4" thicker bearing stop. The axle is 3/4" too short now. After I got over the frustration I had to laugh. At least I'm heading the right direction.

The axles arrived. Tell me what you think. I picked up the round stock for the companion flanges. Off to the machine shop in a couple of days.

That is some nice work there. You've covered a lot of bases in your suspension modifications. You've gone far beyond simply adding 5 bolts and positive offset. My attempts are to create a viable and simple alternative to the major fabrication you've undertaken.

Not now. I'm threading to use the standard 280ZX lock nut. I've never seen a failure although my exposure to such things is limited. It would take a crap load of torque to cause the axle to fail there. In my mind, applying factory recommended torque would suffice holding things together and eliminate fractures. The nut could only go so much bigger considering the constraints of the hub dimensions.

All of the pieces are in the machine shop (Abacus Racing) in Virginia Beach, Va. The LD crank has been completed and work on the LD block and P90A head are in progress. I'm still waiting for the intake flange to get completed (from Justin) so the porting can be completed on the head.

Yes, the outer adapter is eliminated. The companion flange is drilled to suit the halfshaft application. The flange is extended 19mm so it matches the 19mm offset of the Z31 front hubs. This allows using a set of wheels/tires of the same size for rotation. I prefer running the same width wheel/tire all around. The added 19mm will not have any measurable affect on axle strength. The manufacturer indicated no problem doing this. They produce massive numbers of axles for the major car companies too. The axle could just as easily be machined to the stock offset but same larger spline diameter, if desired. Spacers are eliminated. The flange is 5.9" diameter and round. It can be drilled to whatever bolt pattern the end user wants. I chose the 5 x 4.5" because it opens up the option of wheels available and the 19mm positive offset is very popular.

The initial flange will be 4.5" in diameter with a small lip to accept my 930 CV joints. This flange will be thinner overall than the stock flange/adapter I'm using presently. This will provide for a slightly longer axle shaft and help boot clearance from the E-brake bracket too. Once I'm satisfied with that then other diameter flanges can be produced and drilled to accept the stock 4 bolt, 6 bolt tulip, or later 6 bolt CV flanges. One thing I failed to mention is a larger oil seal will be needed at the inner bearing. Also, since the wheel flange is offset 19mm, the stock dust shield will not work. I'm looking to use a large seal on the outside of the outer bearing or have a new dust shield fabbed at yet another local metal shop as a replacement.

The preliminary set of S30 5 x 4.5" stub axles are on their way to me. They are positive offset 19mm to match the Z31 front hubs. The stock 1.25" bearing ID is retained and the spline diameter is now 1.245" and is now a 29 spline count. That's a .150 jump in diameter! This beefs up the axle where they traditionally break but eliminates the cost of machining the strut housings for larger OD bearings (the only way to get a larger bearing ID and larger axle diameter over stock). The threads for the lock nut will need to be threaded a my local machine shop. I've ordered the 4.5" round stock to fab the companion flanges. Once these are machined they'll be sent out for broaching at a specialized shop. They will resemble the full diameter axle shown in post #8 but are necked down .005" between the bearing seats to ease bearing installation. By the way, the flange shown in the background of that picture appears to be a Chrysler or AMC pinion flange. I'll post pictures soon.

Any updates, Justin?