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I have beat the search engine to death on this topic and I have decided that since we Zx'ers have the place to do it; We should put some pertinent info for proper suspension modification/ design here. I have been cruisin' thru the 510 forums to scope some of their info and I like what I see and the S30 guys have their suspension dialed in on this forum. We are behind the 8ball here folks. I was thinking along the lines of compiling some data on the stock weight distribution/ spring rates and rear crossmember/trailing design of our cars to get a base line. Then we could work from there. So Let's hear it, We can all gain from this so lets chip in if we got information on this topic.

thanks'

Jason

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modern-motorsports has stuff that will put coils in all 4 corners, but pull out your checkbook

 

except their option for the fronts aren't that great...

 

I've heard about the 240SX suspension could be adapted to the 280ZX (the springs/shocks anyways). I plan on doing this, but only so I can go lower :P

 

I've got Tokico HP shocks on all four corners with some no-name "coilover" springs all around (the ones with the adjustable spring perches). For some reason it's really bouncy, but I'm sure it's because the springs are too stiff and I've got my car too low. However, in flat turns, the car handles like it's on rails (for me, at least) even though I'm only on stock wheels with 195/65-14 Falken Ziex ZE912 tires.

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One of the guys on my local forum has S13 coilovers fitted to his 280zx. It came up really well. There is also a local manufacturer that has made weld on coilover sleeves that fit straight on the lower struts. It costs $500AU for a full set including coils and helper springs. Not a bad price and very easy to fit. Here is a link to show you what I mean.

 

http://www.viczcar.com/forum/index.php/topic,4075.0.html

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Here are the stock spring rates F/R in the S130 126lbs/126lbs.(These rates should be applicable for all s130s from 2+2 to coupe na/turbo etc) This should give us a baseline to work from. With this information I at least have a better understanding of why my Tokico kit rides like a blockwheeled wagon on the street. Spring rates for my kit are F/R 200lbs/175lbs. But I don't understand why with a rear trailing arm suspension that tokico didnt stiffen up the rear springs to compensate for the "Roll" that is indicative of that system. Also the stiffness isn't the cure.It's part of it. what is also needed to be adressed is the front/rear camber/toe of the car after it has been lowered. Furthermore the run of the mill alignment shop ain't gonna be to correctly align your ride after kit install without the addition of some adjustable suspension hardware. i.e. adjustable tension rod, the addition of some bumpsteer spacers etc.. Right now I am looking at some brackets for the rear to avoid blowing serious coin on a custom built adjustable rear crossmember for our cars. I'll post up with info as we come up with it.

Side note here: I have seen some brackets on motorsports for rear adjustability...I do not like the looks of this kit, it seems problematic and that is why I am researching alternatives.

Jason

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Try search by make. Click on datsun. They use offset bushes for camber adjustment for the rear. The site also has some basic suspension tuning tips that are useful for beginners. Ie, how to adjust for better turn in or to counter under / over steer etc. They also make custom anti-sway bars as well. The guys are super helpful and are just as into modifying cars as we are. ;)

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Seem like a nice set up though the except i dont see usage of caster adjustment on a stock lower control arm. as it would just strain the bushing. To actually use them you need a heim joint adapted to your lower control arm (witch if you are serious about track times you would have to start with)

 

So what would we do or have you done to control rear trailing arms.

the kit offered by K-MAC would be nice for mild track use but as far as i can tell doesnt give me suffiecient movement. PLUS Lots of people on the e30forum.net board have them. on their beamers and supposedly DO NOT keep their alignment, no one I have talked to like's their K-Mac's style bushings, they don’t stay in position. so you keep adjusting.

 

Only way (in my book) for a track or fast street car is a heim joint set up and some slotting if you dont mind the rattling! Im working on it right now for my track toy.

Basically it will be like the guys with teh e30's do. being on tracks in europe you run into dozens of them, so why not 'borrow'a proven concept/

The e30 has traling arms like the z31 with a seperate strut and strut

 

anyhow here is the 'magic'

 

tarm1.jpg

 

Note that this is not a good example but the only i could find, to make it work you need to move the pivot point.

These adjusters only move a few millimeters, but suppose it could move 1". So let's adjust that outer toe adjuster on the right side of the photo a full 1" towards the top of the photo. Heim joints or not, that thing is going to bind up.

 

Anyhow you catch my drift!

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Yeah, that makes sense. There is a lot of load on those points and if you just have offset bushes it would no doubt spin in the trailing arms causing it to go out of alignment. I'm happy with the rear geometry at the moment and I won't be doing any really serious track time for a while at least. Never say never. haha.

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Yeah, that makes sense. There is a lot of load on those points and if you just have offset bushes it would no doubt spin in the trailing arms causing it to go out of alignment. I'm happy with the rear geometry at the moment and I won't be doing any really serious track time for a while at least. Never say never. haha.

 

All depends on how low you are ;) What kind of coil overs etc can you get down under for these cars?

 

BTW for sake of the this topic, my zxr has mixed z31 r32 suspension bits, and home made coil overs.

 

The rear 5 lug swap is easy! it is literaly bolt on!

 

The fronts take some adaption but you could use a z31 set up as i did on my ZXR

 

So the rears swap fairly easy! You need to run the z31 cv's though.

Good part is that apart from the hubs being a direct swap, so are the bearings, brake disk and 87 calipers!!

 

Here comes the tricky part, between the two wheel bearings there is a spacer it needs to be the correct lenght, so mayby not as much tricky as needing the right parts for the job, and to be sure that you dont get funky bearing loads.

 

Note that because the Z31 stub axle is tapered, use the Z31 distance piece (bearing spacer) as the Z31 “B” spacer is the same length (55.95mm) as the ZX “M” spacer. If your 280ZX rear lower control arm housing needs the “N” length spacer (55.85mm) use the corresponding Z31 “A” spacer and if you require the “P” length spacer (56.05mm) use the corresponding Z31 “C” spacer.

 

This opens up a lot of possibilities for 280ZX applications as the Z31 stub axle came in three different varieties: a four-lug hub, a five-lug hub and a five-lug hub that used a vented rotor (which has a thicker wheel mounting flange). Utilizing either the turbo or the non-turbo Z31 companion flange you can use either the ZX CV axles (3 bearing joint) or the stronger Z31 turbo CV axles (with the 5 bearing joint).

 

Strange thing performancewhise but I noticed that the diameter of the ZX stub axle is actually smaller (30mm vs. 32mm) than the first generation 1970-78 Z cars. The Z31 stub axle starts out at a 30mm diameter but then it tapers out to a diameter of 35mm where the wheel flange is. Nice upgrade.

 

The fronts need some work to extend the control arm etc. nothing to fancy, but still something to take in to concideration

 

 

The Track toy has an s13 coil over set up adapted to the stock bottom end (spindle).

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A company called Otomoto here sells HSD coil over sleeves that you weld on in place of your spring perches. You just cut/grind off the factory spring perches and then slide the sleeve over the strut tube and weld it at the height that you want. It has nearly 80mm adjustment so most of the guys are welding them in place so the highest adjustment is at factory ride height and you can adjust down a fair bit. As for complete coil overs, I don't know of any that sell the complete coil over. Some guys are using S13 coil overs instead.

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Here's another supplier for full coil over kits for the S130. It obviously requires welding to install like the aussie company and are similiar. It looks pretty good as far as race application and quality but there's not much for reviews. (pretty pricy too)

 

http://www.horsepowerfreaks.com/performanceparts/Nissan/280ZX/Suspension/Coilovers

 

Mike

1983 Supercharged ZX

http://img.photobucket.com/albums/v186/280zedx/DSC01190.jpg

Coilovers_GT_Pro_Damper_System_LRG_thumb.jpg

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I agree completely, Frank. I have looked into the Datsun 510 forums and have found some nice heim joint fabs they are doing. I am collaborating with one of their guys to utilize zedX dimensions and try to put together something for us! Here are some of the datsun 510 pics.

Not zx spec yet... what do you think? Does anyone know the width of the stock rear trailing arm Bushing btw LOL?

Jason

Heim joint 510 A_thumb.JPG

Hainjoint 510B_thumb.JPG

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Same problems involved with lowering I would assume. The only way to pull it off with our cars would be to lower the Trailing arm mount locations and possibly block the rear suspension tophat or upper shock mount. just my initial thoughts tho

Where the front of the rear suspension mounts to the undercarriage is rusty and going to be rebuilt(in front of the axle) Was going to ask if that could have a spacer put in and was thinking of the strut tower also..thank you.

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If your talking about where the Crossmember mounts to the uni-body I think that would help keep stock alignment.... You will have to adjust rear shock/spring mount to accommodate for the difference in height caused by the crossmember mount. IMHO.... and we all know what opinions are like. You may not be very happy with this car raised up on the rear-end. It is already prone to roll-out due to the trailing arm setup. Elevating your weight may not serve well. unless you want strictly a straight line machine. In that case you will have some room for big rubber out back which is a plus. Again my $.02

Jason

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I agree completely, Frank. I have looked into the Datsun 510 forums and have found some nice heim joint fabs they are doing. I am collaborating with one of their guys to utilize zedX dimensions and try to put together something for us! Here are some of the datsun 510 pics.

Not zx spec yet... what do you think? Does anyone know the width of the stock rear trailing arm Bushing btw LOL?

Jason

 

Wow that is a nice solution.

however what do extreem loads do to it? would it cause it to go off alighnment? the E30 set up with heim joints has no room for 'sliding'

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The book How to Hotrod & Race Your Datsun has mod info on the 510 rear suspension, once race mod back in the day was to make the semi trailing arm inner pivot point adjustable. Which looks like what those gadgets in post #17 are for.

 

The sweep angle of the arm can also be changed, I recall reading about that on a BMW site. As Frank says, BMW is a good one to copy given their race history.

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If your talking about where the Crossmember mounts to the uni-body I think that would help keep stock alignment.... You will have to adjust rear shock/spring mount to accommodate for the difference in height caused by the crossmember mount. IMHO.... and we all know what opinions are like. You may not be very happy with this car raised up on the rear-end. It is already prone to roll-out due to the trailing arm setup. Elevating your weight may not serve well. unless you want strictly a straight line machine. In that case you will have some room for big rubber out back which is a plus. Again my $.02

Jason

IMHO is exactly what i am looking for..thank you

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Wow that is a nice solution.

however what do extreem loads do to it? would it cause it to go off alighnment? the E30 set up with heim joints has no room for 'sliding'

I haven't checked into wether or not it maintains it position during a flogging. I just assumed that since that was what they were running that all was well.

Good point I'll get back to ya.

Jasob

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