BlackBeaut

Hi Tim, Yes the bar is in double shear, here's a couple of clearer pics: Had a little experiment with material removal on the bar there. I based the bushing sizes on one of the control arm bushes, so at least I know it's the right length! Down side is that they are sleeved for 1", where as I'd probably be looking around 14mm bolt to mount the minibar. As for 45mm, yes that's possibly right. The problem I've got is that the moustache bar I have seems to have been through the wars and is bent in slightly odd ways, so I'm not sure if I can rely on measurements I've taken from it for my datum. The mystery measurement I've got from my bar is around 12mm, can anyone confirm or deny that? What I don't understand is the ArizonaZ bar which, from the pic on the site, seems to be entirely flat, and so would logically move the diff back but apparently doesn't as I haven't read any posts about people having problems with them. Cheers, Rob

Well I've been busy again, got under the car and measured up the mounting points for the uprights and their relationship with the moustache mounting bolts. What's the deal with them? Start at 16mm then taper to 12mm for most of their length. The poly bushes I've got for the moustache bar have got a sleeve for 16mm, don't they just rattle around on the smaller bolt? Weird! Anyway, I've come up with an new, bigger, badder and definitely madder design that combines the uprights and moustache holder. Here's a first pass: As you can see I'm using a much shorter moustache bar that's bush mounted in to the uprights to retain some compliance. It also moves the diff forward, although I'm not too sure how far as the moustache bar I've got seems pretty wonky so I don't know if I should consider the measurements taken from it as correct. If they are though then the diff should be about 45mm further forward then stock, so obviously on good for shortnose diffs and CV axles. Probably need to look at the bracing between the uprights some more again, and if anyone would care to suggest better triangulation in the wings, please do. I'm never quite sure where to stick them! Cheers, Rob

It does strike me that there should be some binding issues with poly bushes but Jon is happily using them with 3/16" toe IIRC. That's why I was wondering about monoballs to replace the bushings. These would need to be installed in some cunning way to prevent the control arms moving backwards and forwards of course! As for rear adjustable arms' date=' did someone mention ArizonaZ? Anyhow, here's my nice and complicated toe adjustment idea. I've not gone for a turnbuckle as with the setup of just uprights and brace bar I haven't really got anywhere good to secure the turnbuckle to so as to prevent it just pushing one side out if the other side has stuck. [center'] [/center] The idea is pretty simple, well to me at least The socket cap bolt moved the bushing caps in or out, thus toe is altered. As each sides movement is independent then corrections could be made for any twisted control arms. Downside is the machining to locate the socket cap head is a bit complicated which would no doubt add to the cost. Having said that I've got no experience with modern CNC milling and it might just not be an issue at all. Ahh, I'm so innocent at times Hmnm, it's just occured to me that it's a bit excessive having the brace bar bolted higher up the upright when it could be used to for the clamping bolts as well. Why didn't I think of that earlier?!! Thanks, it's a shame I can't just hit the print button and out pops the finished article though Cheers, Rob

I really like your diff mount approach Tim, definitely good 'un solid! I think I should point out that the renderings of my idea aren't particularly dimensionally accurate. The long braces shown would be around 20mm square, I'd most likely want to use something like 20x40mm rectangle section. Also the cross plate would be fully boxed in, not just a single piece slapped on top. At the front though, that's based exactly on the Ron Tyler mount that a few people have been using with great success, so I'm pretty sure that end of things will cope. I've been thinking about how best to ditch the exisiting moustache bar design. Linking the uprights to the moustache bar mounting bolts seems like the best idea for overall strength. The tricky part is that I still want some compliance in the rear diff mount, so I can just bolt the diff up to a solid brace between the two uprights. That also means that I'll still need some sort of fixed brace between the two uprights to prevent any flexing between them which would mess a little with the toe on the wheels. Nice can of worms I've found for myself here!! Im getting torn between coming up with a design that can be used by anyone, with any diff, which means that it would have to leave the moustache bar well alone. And creating something nice and different, that would make a great upgrade for my particular requirements. I have come up with a nice and complicated toe adjustment idea though, that would be a bitch to machine Cheers, Rob

Out of interest, does your diff have the large mounting ears that hold bushes? Mine is from an S13 any has small unbushed ears so I'll need to some up with some sort of isolator elsewhere. The big eared versions should be even easier to mount up. Cheers, Rob

Thanks Terry, I guess a 2.5" shift forward giving around a 10degree angle will probably be within reason of the 'significant' torque. That should just be enough to get the fins tucked in nicely as well, handy!! Cheers, Rob

I've thought about moving the diff forward, it would make whatever bracing that happens between the uprights easier as there'd be less interference with the diff cover fins back there. Just not too sure how far it can go without affecting CV angles too much, and how far forward it can go without causing issues with the front cross member. If I can move the diff forward say 4" then I'd get CV angles around 15 degrees (possibly, if my maths is any good!) is that an acceptable value, the CV joints I'll be using from a 200SX are tripod type like the 280ZX, but sightly larger. As for getting rid of the moustache bar, I take it you'd have to really beef up the actual body work that the uprights bolt into? I'm concerned that the 4 bolts that hold the uprights in are somewhat weedy in comparison to the 16mm bolts that hold the moustache bar in. Terry, in your solution I see that you have addition wings that locate on to the moustache mounting bolts, did you add those so you could mount the sway bar or because you felt the four upright bolts weren't enough? Also raised is the question of vibration, I guess it would be possible to bush the cross brace/rear diff holder on to the uprights to help reduce transfered vibrations. At the end of the day I'm building a weekend streetable fun car with good track capabilities. It would be nice though to arrive at a design that others can use, should they wish, with minimal alterations to their cars, for whatever purpose they drive their cars for. Cheers, Rob

Is that the sort of thing you meant? Cheers, Rob

Hi all, Thanks again for the responses, all good stuff. Yup Jon, lining up the verticals with the end of the frame rails isn't essential with this design. As long as the top bolt holes are in the correct location relative the bushes below then it should be fine. At the moment I'm designing the uprights to be 36mm thick which seems to be roughly the thickness of the stock bearing caps on the back. I need to dig out my poly bushes and double check that dimension though. That and every other dimension!! Cross bracing is an interesting idea, I'll mock up a design. Not too sure if there's space at the top to clear the moustache bar at the top, or if there would be any issues with the petrol tank - that's pretty close up there - or if I've even got my head around what exactly you mean. Worth looking at though. Feel free to scribble on my pics. Thanks for the material suggestions John, no doubt I'll be anodizing or powdercoating for protection anyway but better corrosion resistance is always good. Just to recap on my idea for mounting the short nose diff, here's a couple of shots of what I've been thinking on. To be honest I'm not 100% sold on the design, I'm sure it would work, but whether it's too complicated for it's needs is another question. I do like to go a bit Heath Robinson on my designs at times Billet front diff cross member with twin exhaust hoops anyone? You gotta love shiny bits of metal Cheers, Rob

OK, here's a couple more variants with 2 central vertical webs, also more material has been removed to give better clearance for the moustache bar. The other major difference is that I've turned the upright around, so the milled pockets face the rear of the car. I figure that made production sense as then all the milling work would take place from just one side of the billet. The blue surface is the area where extra material has been removed to give the moustache bar clearance. Slightly more radical material removal here, does mean that the top bolts would be easier to access from the front. I'm not suggesting this as a production colour scheme of course cheers, Rob

Thanks for the thoughts guys! JohnC, if you were considering making these which alloy would you opt for? I know ArizonaZ uses 6061T6 for their moustache bars (pretty much the same as 6082 over here) but of the three options that's the weakest. Of course material costs are always an interesting diversion! JonM, I've been reading through the 'toe adjuster' posts for a while now soaking up as much info as possible. For my uses though I'm probaby going with ArizonaZ adjustable arms as my existing arms are a bit knackered and with the exchange rate as it is at the moment it just makes sense. Regarding strength at top verses bottom, I'll draw up a new design that uses a double vertical web but should still allow easy access to the bolts. The reason for all the extra meat at the bottom end is that I'm thinking that the bolts from the lower cups and the rear brace will just screw directly into the upright. Must check dimensions to make sure two holes don't intersect! Of course I could loose a lot of material here if I just went with a bolt and nut arrangement as with the existing uprights, my thinking against this is that that adds another end to the bolt that can corrode and make disassembly all the more fun. I'd love to hear your thoughts on that, just don't forget the weather in the UK sucks 99% of the time Good point about moustache bar clearance, I'll look into that! Aux, I'm not considering mass producing these, the market in the UK is far too small and the exchange rate is against me for selling to the big US market. In fact I'd be more than happy for someone to just rip off the idea, it's not exactly breath taking in it's conception Adding in extra mount points for rear roll bars is a nifty idea though. Cheers, Rob

Hi Guys, I spent a fun few hours on Saturday tearing down my rear end, amazingly no bolts sheared and only one head had rounded. I still managed to swear a bit though to keep up appearances Anyway I've been blast cleaning the parts these last couple of days and frankly I think they suck, lots of rust means lots of weak looking pitted steel now. Given that I'm putting in a short nose R200h with a large finned back cover (from an S12 Silvia, think it's the same as Z31) I'll need to create some kind of rear brace anyway, so I started thinking that why not go the whole hog and create new upright sections as well. Here's some idea of what I'm thinking: gotta dig those camera angles and a little Flash animation here: http://www.equiview.co.uk/240z/anim.html Now I'm always a little wary about aluminium due to it's fatigue life issues but it's been years since I've been involved in real engineering and materials so maybe it's not so much an issue now. The 3 alloy options I'm considering are 2014, 6082 and 7075 all T6 treated. Spec details here: http://www.metalfast.co.uk/stocks.htm Also any design critique would be greatly appreciated, are my webs too thin at 5mm or too much even? I want to keep as much space as possible around the top mounting bolt heads so that it's as easy as it can be to get spanners on them, as that was something I discovered to be a lot of fun on the tear down. Admittedly with the R200 moustache bar being behind the uprights this should be a lot easier. BTW, does anyone know of any freeware CAD software? I do all my 3D stuff in an ancient animation package, on an ancient Mac, dimensions are pretty difficult to get right. cheers, Rob

Hows about using any of the RB turbo engines, leaving them with turbo spec internals etc. but sticking a supercharger on instead? NA sound, blown performance? Jus' a thought Cheers, Rob

Man, has word about this POS made it across the pond?!!! Worse thing about it, other than the fact it exists, is the price he's asking, £10k is pushing $19k. I love the way absolutely nothing is disclosed about what it was built up on, probably got a 1.2l 4 pot in there Cheers, Rob

Same dream, different sides of the planet, bit worrying really Jamie, could you tell me the diameters of the 300ZX CV shafts for reference? I've just measures the 200SX shafts that I have, the main shaft is 28mm, the splined end is 30mm. Also they use tripod type CV joints like the 280ZX, although they're a bit larger. I believe the 300ZX uses Burfield joints with balls and cage. Any idea of the advantages/disadvantages of one design over the other? I agree that finding alternative R230 diffs seems be a bit of a tough quest, made even harder in the UK by Nissan's smaller range of cars, and most of those are crappy compact FWD types. Cheers, Rob

Not sure if this was in reference to my post or not but just to clarify, the 5 stud hubs I've got are from a normally aspirated 300ZX not a TT, the NA uses a 4.08:1 R200v AFAIK. Do you have any pics of your rear set up Ben, is it basically the same as the early Zs rather than the Z32, obviously there's going to be some differences due to the trailing arm set up. I'd imagine though that like Jamie, and eventually myself, in order to convert from stub axles to later style hubs would require some major reworking of the strut/hub housing. For my end needs I think I'll be well sorted with 29 spline axles from a 200SX. I'm going with a 3.0l stroker EFI, hoping for around 300bhp at the crank, so well within the capabilities of the R200 I've got with Torsen LSD. Another advantage for me in the UK is that 200SX spares are easily available so replacing bust axles won't be too much of a nightmare. Cheers, Rob

Here's some more hub pics for you. The 4 stud is from an S13 200SX, the 5 stud is a 300ZXNA. They both have the same spline count, which I make to be 29. It might be a bit risky but I'd say that the 29 splines is probably going to be standard for all R200 equipped cars, which I believe includes the Skylines. Only the R230 equipped cars will have the big and bad CVs. I don't know whether it would be possible to adapt the 300ZXTT outer CV to a regular R200 drive shaft, I suspect it would be possible with some nice and expensive custom shafts. Hope these pics are of some use to folks. Cheers, Rob

Hi, Don't know if you are checking here anymore but I can't send you an email through the site. I've just stripped a 3.7:1 diff - the LSD centre is going to Latvia of all places - so if you're still looking for a R&P I'm sure we can come to some kind of arrangement that will be a hell of a lot less than a Nissan dealer! Cheers, Rob

That looks pretty damn good Jamie, I guess you're building these to maintain the stock 0" wheel offset. I think my idea of fixing a 200SX upright/knuckle (whatever they're called) to a reworked Z hub will mean I'll end up with a positive offset at the rear. Cheers, Rob

Hi Jamie, I've been thinking of adapting a 200SX rear hub to fit on to my 240Z, not quite as full on as your fab work as that's way out of my league. Just wondering if I could be cheeky and ask if you could send me a couple of front and back pics of your Z strut and let me know a couple of dimensions to see if my idea is even conceivable. Lord knows when I'll actually get around to stripping my rear suspension down, hopefully not too long though! Hope you don't mind that I've taken the liberty of borrowing from your pic to show the dimensions I think I need to know at this stage. A and B are the distances between the bolt holes that hold the drum backing plate on, C is the outer diameter of the stub axle housing. BTW are you going to be using the Z32 drum handbrake and caliper set up on your struts or do you have something else in mind? Cheers, Rob