tonycharger72 Posted February 23, 2009 Share Posted February 23, 2009 People seen these goodies yet? http://www.arizonazcar.com/strassy.html Quote Link to comment Share on other sites More sharing options...
blue72 Posted February 23, 2009 Share Posted February 23, 2009 I thinks it's fair to say that the majority of us have probably seen Dave's stuff at some point in time and lusted over it. There are members here running the same setup you linked to. Quote Link to comment Share on other sites More sharing options...
JSM Posted February 23, 2009 Share Posted February 23, 2009 I love looking and drooling over the parts on the website, but that has got to be one of the worst websites I have ever visited. This is my opinion, but the navigation really sucks and I don't care for the layout at all. Quote Link to comment Share on other sites More sharing options...
JMortensen Posted February 23, 2009 Share Posted February 23, 2009 Get past the bling and analyze the part. Think of the loads the upright takes, and then think to yourself "Is a flat plate the best shape to deal with these loads?" Compare to real race car uprights. See a difference? Single shear mounting of the strut to the upright? Connected with bolts no less (built in stress risers)? The one brace he does have in there is on the opposite side from where the strut connects? And then there are the arms he has connected to it, which are another case study in bad design. This is billet bling crap guys. Just for comparison's sake: http://www.luxonengineering.com/pdf/news_9-25-2008.pdf http://www.luxonengineering.com/pdf/asme_presentation.pdf Quote Link to comment Share on other sites More sharing options...
doublexl240z Posted February 23, 2009 Share Posted February 23, 2009 Mr. Mortensen, You are Correct!! That would look really really biatchin on a not so fast car though!! Up until you load it... at say... Turn 1 at Sebring or the corkscrew at Laguna. Then, its all over. It would be neat to run it and have cameras and telemetry showing deflection and alignment changes under load. That is, unless I had paid almost 4000 dollars for rear suspension. My 2 cents... your mileage may vary!! Quote Link to comment Share on other sites More sharing options...
tonycharger72 Posted February 23, 2009 Author Share Posted February 23, 2009 I thinks it's fair to say that the majority of us have probably seen Dave's stuff at some point in time and lusted over it. There are members here running the same setup you linked to. I thought these rear suspension bits were new? I love looking and drooling over the parts on the website, but that has got to be one of the worst websites I have ever visited. This is my opinion, but the navigation really sucks and I don't care for the layout at all. Yeah I know , finding stuff can be a bit of a pain! This design moves away from the flat plate design (well sort of), is made out of steel - however no gussets, http://www.technotoytuning.com/racing/ A friend was going to make a rear setup similar to AZC's but from 32.5mm thick 5083 alluminium, I ran it past my local engineer and he was initally keen on it being made out of steel, but gave the ok for the alluminium version, It will basically be a big flat backing plate, 32.5mm thick for the hub, rotor to bolt to - strut tube arrangement similar to TTT and Rear LCA connecting piece would right angle off the bottom - welded on though, not bolts! Plus having seen that, maybe a gusset either side at the back, However, even without the gussets the engineer was happy to pass it for road registration, Quote Link to comment Share on other sites More sharing options...
tonycharger72 Posted February 26, 2009 Author Share Posted February 26, 2009 Get past the bling and analyze the part. Think of the loads the upright takes, and then think to yourself "Is a flat plate the best shape to deal with these loads?" But wouldn't the thickness and material you construct it out of take care of those sorts of issues? Looking at that fellows rear axle housings (from the link you posted) they appear like they would weigh as much as a paperweight, like he has optimised the design so he was able to remove as much meat as humanly possible from the design, If you didn't have access to a CNC machine so werent able to replicate his sort of design, making the backing plate out of absurdly thick alluminium should take care of these design "faults"? Compare to real race car uprights. See a difference? Single shear mounting of the strut to the upright? Connected with bolts no less (built in stress risers)? Sorry, I may have missed what you are saying here ! Your not referring to the strut-to-backing plate portion - that appears welded? Are you referring to the Backing Plate-to-lower portion that than mounts to the rear LCA's? I think it is awfully tricky to weld together alluminium that thick, like have to get it hot enough that the metal changes composition or something? BUT..........look at RX7 S5 front struts, basically has two bolts that hold the McPherson strut to the spindle, basically these two bolts hold up the front of the car - couldn't imagine it would be that different from this application? Quote Link to comment Share on other sites More sharing options...
JMortensen Posted February 26, 2009 Share Posted February 26, 2009 But wouldn't the thickness and material you construct it out of take care of those sorts of issues? Looking at that fellows rear axle housings (from the link you posted) they appear like they would weigh as much as a paperweight, like he has optimised the design so he was able to remove as much meat as humanly possible from the design, If you didn't have access to a CNC machine so werent able to replicate his sort of design, making the backing plate out of absurdly thick alluminium should take care of these design "faults"? Go back and look at the original uprights for that CSR Stohr. The originals are not some crazy FEA inspired design. They're pretty simple aluminum pieces shaped like a box more or less, but they're at least shaped to deal with stress in different planes. Could a flat plate work if it was thick enough? Yes. Is that a crappy way to design race parts? Yes. If you're going to all this hassle to design your own upright and connect it to your own control arm, why use the spindle pin? Why not use a double shear connection for a front and rear rod end that bolt up into the bottom of the upright? Why use a conventionally mounted caliper instead of a radial mount caliper? Why use an H arm at all? Really, if you're going that far you pretty much have carte blanche. Might as well use it. Your not referring to the strut-to-backing plate portion - that appears welded? Are you referring to the Backing Plate-to-lower portion that than mounts to the rear LCA's? I think it is awfully tricky to weld together alluminium that thick' date=' like have to get it hot enough that the metal changes composition or something? BUT..........look at RX7 S5 front struts, basically has two bolts that hold the McPherson strut to the spindle, basically these two bolts hold up the front of the car - couldn't imagine it would be that different from this application?[/quote'] The STEEL threaded tube that the strut screws into is welded to the angled STEEL bracket part that connects the threaded section to the upright. This bracket is then bolted to the aluminum upright. I thought there was a picture of the bracket bolts, but I can't seem to find it now. It's not welded though, because they are aluminum and steel. RX7 struts, like in the pictures you've posted before are a lot different in several ways: 1. They're double shear. This is a huge distinction. HUGE. 2. If the strut connection you're referring to fails, the wheel doesn't fall off the car, because it is a SLA suspension system and the control arms hold the upright independently of the strut which just suspends it. There are quite a few MacPherson struts that would allow the wheel to come loose (like the TTT design for instance, or a Mustang, I think the 240SX too), but you're bringing up the RX7 and it is an important distinction in that design and those others all have double shear mounts for the strut to the upright. 3. They're connected to a properly designed upright. Quote Link to comment Share on other sites More sharing options...
240hoke Posted February 26, 2009 Share Posted February 26, 2009 Im am going to have to completely agree with Jon on this one. It would have been SOOO EASY to put the strut and heim joints in double shear and it would not have cost significantly more either...especially since everything is being CNC'd to begin with..I would expect it in a 8K dollar suspension setup. What Im even more curious in though Is how they came about there designs and how they have been tested besides "they work". I like there stuff and I think its great that they are producing Parts for our z's but I have defintly been pretty wary of there billet aluminum controls arms. I would like to see some FEA on those LCA's vs. Stock. I would dare to venture a guess that it isnt much stronger then stock...if at all. Most of the load on the LCAs is a compressive force from the wheels inward. Quote Link to comment Share on other sites More sharing options...
tonycharger72 Posted February 26, 2009 Author Share Posted February 26, 2009 Thanks for the comments mate, this is more from a persective that I am actually building my own rear's and mine were more or less going to be (simpler) but similar to AZC's - I really wanted more information on what was wrong with it ! Quote Link to comment Share on other sites More sharing options...
tonycharger72 Posted February 27, 2009 Author Share Posted February 27, 2009 This is a design I have come up with in my head................. I dont have anything more sophisticated than paint, so the drawing is a touch basic !!! However, the principal idea is based upon replicating what Luxon do, with the provision for a strut, not a top a-arm! Basically, grab a piece of 2-3" thick mild steel, put a whole through for the the axle and remove metal for the hub to bolt to - guess also act as a weight saving device, The rear LCA's would need to be increased in length as this design does away with the bolted/welded together connecting supported that TTT or AZC use, and the LCA simply bolts right up to the backing-plate (bolt through at the bottom of the backing-plate!!!) The strut would be connected in a similar fashion as TTT's model users, or like the RX7, two bolts with a welded on piece to the back of the backing plate - I say welded as I don't have a CNC machine and don't know you could easily get steel that thick to incorporate this part !!! This design though, requires you to construct longer LCA's and custom strut tubes - maybe that is more why AZC's are the way they are........to work with his existing Rear LCA's and Strut designs, make more sense to create complementory products instead of ones that make existing products obsolete - just a thought! Quote Link to comment Share on other sites More sharing options...
tonycharger72 Posted February 27, 2009 Author Share Posted February 27, 2009 Oh, almost forgot - there is no provision for brakes on my diagram, but the backing-plate would be designed to use stock Z32/R32 style brakes with drum type handbrake - that or a suitable "lever" style cailper, either will effect caliper mounting ears or a bracket of some sort! Quote Link to comment Share on other sites More sharing options...
S15 200sx owner Posted April 6, 2009 Share Posted April 6, 2009 Interesting thread guys, watching with great interest, as I am still considering weather I go with a TTT type backplate setup to use the Z32tt/R32 GTR rear hubs/outer cv's or weather i go with the new improved MM stubs with the larger dia and more splines, and matching companion flanges to suit the big 6 bolt Cv's Keen to see where you all go with this. Quote Link to comment Share on other sites More sharing options...
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