tonycharger72 Posted January 24, 2009 Share Posted January 24, 2009 I wasn't 100% sure where to post this, here or in metal fabrication, Anyways, I am slapping in new frame rails and had an idea, I am using a 1UZ and it would make life so much easier to use a crossmember that resembles a "K" frame - Like in your 60's/70's Mopars (if anyone has a Mopar , What I am thinking is, Remove the TC bracket, ditch the stock TC rod and make a new crossmember, This new crossmember will bolt in where the stock crossmember bolts in at the front, and at the back, will bolt in where the TC bracket used to be! Then, make an A-Arm, combine the TC Rod and LCA, make them one uniform piece, Instead of the TC mount facing at an angle, it would be angled the same way as the LCA mount - pointing straight outwards, Basically something like this - sorry its a pretty crude drawing !!! Note: the little blue tabs are bolts, & the crossmember, it will sorta look like this, basically it's intended to do away with the stock TC bracket and TC Rod and use a pivot similar to that used for the LCA to crossmember! This makes engine placement for me a lot easier - not real keen on welding ears to the chassis rails and my sump gets in the way for a 2nd crossmember, also looks like someone had the bright idea to chisel out the TC rod hole,, This design is just a lot easier to make the rotating the TC rod like it is there now, Quote Link to comment Share on other sites More sharing options...
fastzcars Posted January 24, 2009 Share Posted January 24, 2009 You mean kind of like this? I believe it's a 3rd gen RX7 LCA. http://album.hybridz.org/showphoto.php?photo=5373 Quote Link to comment Share on other sites More sharing options...
tonycharger72 Posted January 24, 2009 Author Share Posted January 24, 2009 Thats exactly it!!! More information please , Are you using the stock Z ball-joint? got any more pics inside the engine bay of the subframe? where does the TC control arm pivot sit in relation to the old Rod End? Would be a lot easier if I don't have to make my own control arm!!! Quote Link to comment Share on other sites More sharing options...
fastzcars Posted January 24, 2009 Share Posted January 24, 2009 Sorry tony , not my car! I just remember that someone was doing this! You might want to PM "marcg". As a matter of fact I found his album here and found this for you! I guess it true "great minds think alike!"http://album.hybridz.org/showphoto.php?photo=6241&ppuser=11544 Quote Link to comment Share on other sites More sharing options...
tube80z Posted January 24, 2009 Share Posted January 24, 2009 The only thing you may want to think about with this design is how you adjust caster. And the pieces that look like they would be going under the frame rails won't be serving much purpose. The TC bucket area is fairly stout if you want to connect to that. Quote Link to comment Share on other sites More sharing options...
JMortensen Posted January 24, 2009 Share Posted January 24, 2009 The only thing you may want to think about with this design is how you adjust caster. Agreed. Porsche 944 is set up the same way, and to adjust caster you can move the rear pivot left or right on the frame rail. On that car you can only move it maybe 1" or so, which gives a pretty small range of adjustment but also moves the front and rear control arm pivots out of square with the rest of the car, essentially turning the front control arm into a semi-leading or semi-trailing arm. The amount of out-of-squareness may not be enough to really feel a difference when you're driving, I don't know. But I do know that people race Z cars with anything from 3 to 10 degrees of caster, and you wouldn't have anywhere near that range of adjustment with this style arm. Unlike some other cars there isn't a whole lot of room up top to adjust it either. The 944/RX7 style control arm would allow for more room for the wheel to turn without contacting anything. Might be a good idea for drifters... Quote Link to comment Share on other sites More sharing options...
tonycharger72 Posted January 24, 2009 Author Share Posted January 24, 2009 Thanks for the link FastZcars! Some really good information there! I wonder why that fellow mounted the LCA pivot points so much further outbound...............have to track that guy down me thinks! Also Mitsubishi have made more than one different car, would be interesting to find that ball-joint without more information ! This is my first attempt at solving this one - basically keep the stock TC locating, just open up engine mount area on the chassis rails and make a wider crossmember, Looked like sh#t ! The only thing you may want to think about with this design is how you adjust caster. And the pieces that look like they would be going under the frame rails won't be serving much purpose. The TC bucket area is fairly stout if you want to connect to that. The bits under the chassis rails would be were I am mounting my engine, not all that keen on slapping stuff onto this area, looks messy and it would annoy me, so would end up just pulling it all out and doing it again anyways ! I figured I would lose camber adjustment at the TC pivot, but thought I might have a little bit more space up in the strut tower to modify caster, did not realise it was that tight up there................ What about if I change the crossmember design slightly, basically replicate what the TC buckets are doing now? this would also mean just using stock LCA and TC rod, but then I would have the adjustability I would lose with a single unit, Sorry, this is a really crude drawing Quote Link to comment Share on other sites More sharing options...
Dayz Posted January 24, 2009 Share Posted January 24, 2009 Check Marcs page for the LCA http://www.cardomain.com/ride/563982/3 Quote Link to comment Share on other sites More sharing options...
tonycharger72 Posted January 24, 2009 Author Share Posted January 24, 2009 I did, thats why I asked, I wonder why that fellow mounted the LCA pivot points so much further outbound Because it doesnt look necessary, even with the extra width of VH45, think it would fit within the chassis rails without the TC bucket in place - then u could mount the A-Arm underneath the chassis rails, not on the outbound side of the chassis rails.............however never tried to fit a VH45 so this fellow would be the expert!!! Also he had to use a pretty crazy steering rack coupling, so sure that had something to do with it as well!!! Quote Link to comment Share on other sites More sharing options...
NZeder Posted January 26, 2009 Share Posted January 26, 2009 You might want to talk to RBZ260 on the AUSZCAR site or The SA Zed forum - thezgarge.com and then Marc (is it MarcS or MarcG?) and see if you could come up with a setup that uses both these guys ideas and you have more RX7 setup under the car with that A arm type setup and a spindle setup that will allow for camber changes via the new front strut. For caster could you not have this as the top of the strut? Here is RBZ260 front setup using Rx7 struts and spindles and I think a Mits ball joint to get the stock LCA to connect up to the spindles. Quote Link to comment Share on other sites More sharing options...
tonycharger72 Posted January 28, 2009 Author Share Posted January 28, 2009 Thanks for the information mate, had a really good look at what that fellow did on Newcastle Z cars! Really clever the way he did that conversion! Closed up the end of the Z LCA and made it suit the RX7 ball-joint so he could use the RX7 spindle & Struts (I assume stock RX7 ball-joints), then modified the top of the RX7 struts to suit the Z strut tops! And he has climate control in his Z !!! Think that is 1978-85 RX7 gear, pretty much the same sorta of stuff that is the Datsun stock, I was thinking of the A-Arm and TC Rod being one solid piece, like the Series 4/5 RX7, I think I have figured it out though, I will build a very similar setup to that 450z fellow from the link Fastzcars/Dayz posted using the S4/5 RX7 Arms! Quote Link to comment Share on other sites More sharing options...
tonycharger72 Posted February 2, 2009 Author Share Posted February 2, 2009 Ok guys, went out last weekend and grabbed some S4/S5 RX7 Lower Control arms and whipped up a crossmember to suit, These RX7 LCA's appear to be different than the USA version as the ball-joints are not detachable, these are all one solid piece - having that area detachable would probably make it a lot easier to get a suitable ball-joint, however will have to wait a see! The new crossmember bolts in front and rear using M10x1.25 bolts, The engine will be mounted of the Front to Back cross-bracing! Shot of the LCA, Rear LCA Housing, Have to throw in a few more gussets and hopefully, if there is room, a cross-brace between the two rear LCA housing's - won't know if that is possible until I fit the engine in! Quote Link to comment Share on other sites More sharing options...
NZeder Posted February 2, 2009 Share Posted February 2, 2009 looking good Tony - but just one thing - I know that on the stock TC rod setup getting a header to pass through the gap between the block, TC mount and the firewall/floor can be a challenge. Looking at this setup it might just make that almost impossible? I am talking about NA setups here were the collector and all those pipes are coming together around this region of the chassis. Quote Link to comment Share on other sites More sharing options...
EMWHYR0HEN Posted February 2, 2009 Share Posted February 2, 2009 It's good to see someone actually taking a plunge and trying this out. Your doing some nice work. However, I would be concerned about weight as your adding a lot of thick material. Also, how are you going to go about adjusting caster? Quote Link to comment Share on other sites More sharing options...
tonycharger72 Posted February 2, 2009 Author Share Posted February 2, 2009 It's good to see someone actually taking a plunge and trying this out. Your doing some nice work. However, I would be concerned about weight as your adding a lot of thick material. Mainly pre-occupied with strength, be an awful shame if the engine took a spill out of the engine bay - but it's tough to say how much of an increase in weight there has been, the the RX7 LCA's are alluminium and most likely weight less than the stock Z LCA and TC Rod, the rear LCA mount's probably weigh double what the original TC bucket would have weighed and then there is the addition of the front to rear bracing for the engine mounts, that would add a kilo or two, I will have to weigh it to see how much more weight has been added! Also, how are you going to go about adjusting caster? I dont know................. Nah, was thinking there is a few options, JohnC's bolt in adjustable strut-tops, give me about a degree of movement Or..............really go to town, the RX7's caster is apparently adjusted through the strut tops as they have lots more room in the strut tower - so I could get rid of my exisiting strut towers and graft in some body work from the RX7 or just make new ones, the R31 Skyline also has massive strut towers, they are alot more plentiful than S4/S5 RX7's!!! This would give me freedom of movement for my strut's, Then I could possibly run the entire front suspension from the RX7, upper control arms included or just stick with one Control Arm and a Strut, The only issue with me running upper control arms is the 1UZ, is wide so it overhands the chassis rails a little bit, this will probably interfere with the Upper Control Arm mounting points on the inner fender walls - If I was running a straight 4/6 would be a lot easier!!! I need to lay my hands on some S4/S5 chassis diagrams, like the ones floating around in this forum of the 240-260-280z chassis, that would tell me if this is a possible option with my engine choice! 2nd option is a lot work though..........but I have come this far, why not really go nuts!!! Quote Link to comment Share on other sites More sharing options...
260DET Posted February 2, 2009 Share Posted February 2, 2009 Interesting idea, hope it works out. An alternative, which you probably considered but discarded due to the steering rack being behind its Xmember, is to use an entire S13/14/15 front end. The only major job with that would be to strengthen the front Xmember to mount the strut rods there. Beauty about later model gear is the bolt on aftermarket stuff available, five stud hubs and better geometry. Quote Link to comment Share on other sites More sharing options...
JMortensen Posted February 2, 2009 Share Posted February 2, 2009 Or..............really go to town, the RX7's caster is apparently adjusted through the strut tops as they have lots more room in the strut tower - so I could get rid of my exisiting strut towers and graft in some body work from the RX7 or just make new ones, the R31 Skyline also has massive strut towers, they are alot more plentiful than S4/S5 RX7's!!! The RX7's caster is adjusted at the upper control arm, not at the strut top. Grafting on a larger strut tower would work with a caster/camber plate and there are many available. Mustang and Porsche come to mind. Quote Link to comment Share on other sites More sharing options...
tonycharger72 Posted February 3, 2009 Author Share Posted February 3, 2009 Interesting idea, hope it works out. An alternative, which you probably considered but discarded due to the steering rack being behind its Xmember, is to use an entire S13/14/15 front end. The only major job with that would be to strengthen the front Xmember to mount the strut rods there. Beauty about later model gear is the bolt on aftermarket stuff available, five stud hubs and better geometry. Yes, rack behind the crossmember makes engine fitiment really, really tricky but was also worried about the increase in track - actually the track really stuffs me around! I am limited to 25mm increase total for road registered car, so this rules out the S13/14 gear - I guess I could have looked at adpating the LCA's, struts and TC Rods from the S13/14 onto my Crossmember, but sure would have been interesting to connect up the steering knuckle to my front mounted steering rack !!! I know hey, even a quick search on EBAY and there is lots of S4/5 RX7 stuff floating around!!! - Thats why I am going to try really hard to stuff the entire RX7 front suspension under my car, lots of stuff for S4/5 RX7's !!! The RX7's caster is adjusted at the upper control arm, not at the strut top. Grafting on a larger strut tower would work with a caster/camber plate and there are many available. Mustang and Porsche come to mind. Oh okay, It kinda sucks, I have found it very difficult locally to get my hands on upper control arms, struts or spindle for the S4/5 RX7 - Even vieiwing the suspension setup and mounting points has been difficult, only been able to crawl under a friends car! Really need to get my hands on chassis diagrams and the complete front suspension from the RX7 before I will know how to move forward with this! Ideally I would run the upper control arms and retain the stock Z strut top and shock towers - in the long run that would probably be a better solution then grafting in shock towers from some other car! Quote Link to comment Share on other sites More sharing options...
tonycharger72 Posted February 3, 2009 Author Share Posted February 3, 2009 looking good Tony - but just one thing - I know that on the stock TC rod setup getting a header to pass through the gap between the block, TC mount and the firewall/floor can be a challenge. Looking at this setup it might just make that almost impossible? I am talking about NA setups here were the collector and all those pipes are coming together around this region of the chassis. Yeah thought about that - going to have the exhaust pointing forward and exit out the front of the car , just kidding!!! The stock exhaust manifolds are kinda like "logs" that run down the length of the block and shoot of into the engine, Before I could put the engine into the car originally I had to cut the exhaust to cat converter flanges off as they hit the TC buckets, These new "TC buckets: (can't think of what else to call them ) are higher as they sit above the chassis rails, not just in line with it like the originals but they are sloped back - so the Log style exhaust manifolds should run over the top of the brackets and then I can right angle in down under the car and out of the engine bay! I think I will struggle to run extractors - stock exhaust shouldn't be to much of a drama, but extractors would be interesting, however, even with the car stock running extractors in there was going to be interesting !!! Quote Link to comment Share on other sites More sharing options...
tonycharger72 Posted February 3, 2009 Author Share Posted February 3, 2009 I just went and had a look under a S4/S5 RX7 - it doesn't have upper control arms, it has a spindle and strut mounts to the top of the spindle - pretty much the same sort of arrangement that is found on the Z, The Caster is unadjustable apparently, only camber adjustment through the strut tops! Therefore, it shouldn't be all that difficult to just install the entire front suspension from the S4/S5 RX7, No wonder I couldn't find any upper control arms for sale for the S4/S5 RX7!!! Quote Link to comment Share on other sites More sharing options...
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