peej410 Posted March 7, 2012 Share Posted March 7, 2012 (edited) Hey all, After about ten years I am finally wrapping up a 240z project (the running bits anyways) and thought I would share the latest mind numbing edition. A disproportionate ratio of income/free-time/boredom has led me to scratch my head a bit. Then finally my lovely GF asked me one day, If you're M3 handles so nice, why don't you make your Z like it... The fact that I have spare bits from my M3 18x10 track wheels and rubber, spare brakes hubs wheel bearings and even a back half tub kind of pushed the suggestion over the edge. It is still in progress but the car rolls around on its new parts! Onto the stupidity. zm3 by peej410, on Flickr m3rsubmockup by peej410, on Flickr M3 floor minus subframe and rtab by peej410, on Flickr Untitled by peej410, on Flickr Untitled by peej410, on Flickr 421863_10150686697471350_711386349_11646393_688963704_n by peej410, on Flickr 395947_10150686700206350_1964044165_n by peej410, on Flickr photo 1 by peej410, on Flickr photo 3 by peej410, on Flickr photo 4 by peej410, on Flickr Zoey_Tire_Right by peej410, on Flickr Zoey_Tires_Rear by peej410, on Flickr Zoey_Side_Driver by peej410, on Flickr Sorry for the Photo heavy post. Front suspension bits will be fabricated soon. Still have to do some cutting here and there but it rolls. Now time for flares plumbing reinforcing a new dshaft and some fancy shocks. Let me know what you guys think. Edited March 7, 2012 by peej410 Quote Link to comment Share on other sites More sharing options...
johnc Posted March 7, 2012 Share Posted March 7, 2012 That's a buttload of work. I work on both and can see the temptation. Quote Link to comment Share on other sites More sharing options...
rsicard Posted March 8, 2012 Share Posted March 8, 2012 Johnc: What attributes of the M3 suspension make it much better than the 240Z suspension? Please advise. Thanks. Quote Link to comment Share on other sites More sharing options...
bjhines Posted March 8, 2012 Share Posted March 8, 2012 The front suspension is virtually the same. The BMW uses boomerang shaped front lower control arms instead of the short arms and TC rods the Datsun uses. I think the BMW boomerangs put more lateral twisting forces on the frame-rails. Quote Link to comment Share on other sites More sharing options...
peej410 Posted March 8, 2012 Author Share Posted March 8, 2012 The advantage of the M3 rear suspensions start with its camber management characteristics and its toe management under compression. In my case i was more interested in the fact that it is fully adjustable for camber and toe. It has 12in brakes. It converts to five lug BMW which opens up a world of options. Also, hollow robust CV shafts and serviceable clutchpack LSD gigantic 85 mm wheel bearings and plentiful aftermarket support helps too Quote Link to comment Share on other sites More sharing options...
frank280zx Posted March 8, 2012 Share Posted March 8, 2012 (edited) Funny.. i was just working on my e36 'M3' (euro s50b32) track car (see picture) And Xander and i where looking at the diff carrier next to an s30 unit thinking the same.. mainly do the wide availebility of parts and diffs in europe .. Great !!! I still have a seed for an e39 m5 rear subframe in my s130 ... this does make it sprout a bit Edited March 8, 2012 by frank280zx Quote Link to comment Share on other sites More sharing options...
johnc Posted March 8, 2012 Share Posted March 8, 2012 Johnc: What attributes of the M3 suspension make it much better than the 240Z suspension? Please advise. Thanks. Off the top of my head... Front 1. Offset spring and shock axis to reduce friction/bind in the MacPhereson strut. 2. Minimal scrub (2.5mm with 205 width tires). 3. L shaped LCA decouples lateral rigidity from longitudinal compliance. Lateral loads go into the pivot ball joint wile longitudinal loads create a rotation around that ball joint from the rear bearing compliance. Reduces rolling resistance, reduces NVH, and still maintain good braking control and lateral stiffness. Rear 1. Multi-link that decouples the longitudinal load path (trailing arm) from lateral load paths (two angled lateral links). 2. Shock and spring laod paths are also decoupled. 3. Positive compliance - Toe in under braking, toe in under lateral (compressive) loads. 4. Multiple adjustments. 5. No roll steer and good compliance. 6. Good braking pitch axis (anti-dive) with the front trailing arm mount below the wheel center line.' Quote Link to comment Share on other sites More sharing options...
260DET Posted March 9, 2012 Share Posted March 9, 2012 BMW know their suspension stuff. Not that great otherwise but driving impressions count which is where they shine. PS My Z now has 9 degrees front caster so suck shoot BMW Quote Link to comment Share on other sites More sharing options...
frank280zx Posted March 9, 2012 Share Posted March 9, 2012 (edited) Haha Richard since i drive both. ( ok i altered allot on my s130 also the front caster) and you cant really compare the s30 to the s130 suspension wise ( front is better when it comes to caster, but the rear is a debate i do not want to get into) I would say the beamer is in a league of its own, downside being that everything after the e36 tends to get heavy (1300 to 1500 kg for a full build e46). The good part about this swap is that even a more nimble car than an e36 gets the benefits of the BMW suspension without the front axle weight issue the e36 6 bangers have, as in a z the engine is placed more behind the front axle. I would be really interested to see a full caged s30 with a full BMW e36 suspension, you would have stiff light car with e36 handling characteristics. And let me point out that even there you have room for improvement using e46 aluminum boomerangs etc. The e36 like the s30 is a car that still can compete with the more modern cars in a field E36 still get campaigned here against new porches and bmws with success in for instance the German DMV TCC and the belcar series. And the lap times of a well prepped s30 are not far of those A good e36 m3 can do 1:57 at zandvoort, I have seen an s30 do it in 1:59 (6 banger class restricted with mods up to 1982) with a v8 datsun the playfield is a whole different game) Combine those two .. damn this is what i call a seed! the seed being ... m5 under an s130 Picture this under an s130 ....... Edited March 9, 2012 by frank280zx Quote Link to comment Share on other sites More sharing options...
peej410 Posted March 9, 2012 Author Share Posted March 9, 2012 I weighed all the components of both suspension setups in their entirety they are within 12lbs! In the front i am building custom control arms so i can manipulate the roll center back to factory bmw specs in a different chassis. I may someday swap the whole front sub in but for now i am not cutting off my pretty TC mounts. I am still waiting on quotes for the rear shocks. Looking at Bilstein ASN and Penske 7500 with a 300lb spring to start. Opinions? I spoke with JohnC yesterday and he is getting me some final data on the Rtab relationship to the body. The Rear trailing arm front bushings (rtabs) could not go any higher in the body... That decided where the subframe would go.. I put the CVs and diff in and found that the CV angles arent great at ride height. Ill be raising everything into the body over the weekend Quote Link to comment Share on other sites More sharing options...
frank280zx Posted March 9, 2012 Share Posted March 9, 2012 (edited) Keep me updated, Spring rates are very personal from what i found out, i like a firm not harsh ride for track work but only way to find out is trail and error I know the e36 factory backed race cars ran between 360 and 510!!! so for streetable use id stay arround 250 but that is geustimate Edited March 9, 2012 by frank280zx Quote Link to comment Share on other sites More sharing options...
johnc Posted March 9, 2012 Share Posted March 9, 2012 I spoke with JohnC yesterday and he is getting me some final data on the Rtab relationship to the body. The Rear trailing arm front bushings (rtabs) could not go any higher in the body... That decided where the subframe would go.. I put the CVs and diff in and found that the CV angles arent great at ride height. Ill be raising everything into the body over the weekend And I found my Mitchell data set for the E36 is fucked. Haven't run it in a few months and now its all woogy running on the latest service pack for XP. I'm looking for a good backup but for now I've asked a friend to go measure his car. Quote Link to comment Share on other sites More sharing options...
peej410 Posted March 9, 2012 Author Share Posted March 9, 2012 Thank you John! On my E36 M3 I run 600f/800r on Bilstein Gruppe N coilovers. It is VERY firm. But its a total blast so I dont complain much! Quote Link to comment Share on other sites More sharing options...
peej410 Posted March 23, 2012 Author Share Posted March 23, 2012 Quick update. Sub-frame mounts are fully welded in. I purchased some used front bilstein struts from a friend and made some new LCAS for the front. I will update with some actual tech soon regarding camber track width etc. Untitled by peej410, on Flickr Untitled by peej410, on Flickr Already it is apparent that this was a good decision. There is so little bearing drag from the BMW parts that when I first lowered the car down off the stands and with no front tie rods yet, it rolled away from me... in the garage! Luckily i stopped it before it took out the compressor and other things. So, this is the best time to ask... ZG or steel custom flares?! Quote Link to comment Share on other sites More sharing options...
260DET Posted March 23, 2012 Share Posted March 23, 2012 Love your work Frank, going by your experience the BMW suspension under a S130 would be a killer. While the S30 is rightly so the Z car to have the S130 has a much stiffer chassis the weak point being integration of the front chassis rails into the body which is not hard to fix. But I have to say that my S130 with S14 suspension front and back is a faster car than it's driver so I don't know if the BMW setup would be better in the real (amateur) world. The grip you get from just semi slicks slams me around enough as it is Quote Link to comment Share on other sites More sharing options...
luseboy Posted March 23, 2012 Share Posted March 23, 2012 That's awesome to see it on it's own feet. Makes me a little jealous but then I realize that I will never be as good a driver as my Z will handle with upgraded stock-style suspension. I'd say go ZG flares! I love them and will be cutting up my fenders soon for them Quote Link to comment Share on other sites More sharing options...
peej410 Posted March 29, 2012 Author Share Posted March 29, 2012 ZG flares ordered along with a pair of penske 7500 single adjustables for the back. Dont say never... I never thought i would be as fast with my M as i am at the track. Good instructors and confidence in your ability goes a very long way! (and only push your limits in the corners with a lot of run off!) Quote Link to comment Share on other sites More sharing options...
johnc Posted March 29, 2012 Share Posted March 29, 2012 Sorry I haven't got back with the measurement. I have nothing to measure here at the shop and my friend is on to other things right now. Quote Link to comment Share on other sites More sharing options...
Administrators RTz Posted March 29, 2012 Administrators Share Posted March 29, 2012 peej, I've got a '98 M3. Let me know specifically what measurements you're looking for and I'll try to round them up for you. Quote Link to comment Share on other sites More sharing options...
peej410 Posted March 29, 2012 Author Share Posted March 29, 2012 No worries John. RT basically i am looking for the offset from the rtab bucket face to the flat surface of the subframe mounts on the body. Mostly just trying to sort how close i am to OE dimension. Its bery tricky if the suspension is ob the car... Quote Link to comment Share on other sites More sharing options...
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