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Discussion Starter #1
A few things that have come up while working on the rear setup. I found that by positioning the lower shock mount about an inch back, and maybe about 1/2" outboard, I gain tons more clearance for the spring, sleeves,and collars. This will allow the spring to sit lower on the shock, and increase travel. This poses a few issues though. The first being that it will alter the "working lever length" of the suspension arm. This means the force applied by the spring will be placed on a farther point than the stock is, and spring rate will need to be altered. Also, I'm worried about the stock shock mount, and the trailing arm itself, being strong enough to hold up the amount of continuous force that the coilover setup will be putting on the end of the arm. Being that the original spring sits closer into the subframe, and it sits on a fairly beef section of the arm, it's very well supported.

To solve this issue, I have a tentative design to build a support for the underside of the trailing arm. Think of it as an exo-skeleton of sorts for the arm. It will bolt to the underside of the trailing arm, and will extend past the stock shock mount, repositioning the shock as stated above. From the bottom of the support plate, another triangulated support will extend rearward, and meet at the bottom of the new shock mount, offering even more strength. This piece will stiffen the trailing arm, allowing it to resist flex and bending in the center, and play a dual role by placing the shock where it will work the most efficiently. This piece will be part of the rear coilover kit, and may be offered separately. This is pretty much the only way a rear coilover like this will be safe, short of making a new trailing arm from scratch. I could do that, but it definitely won't be cheap.

I also have been thinking about offering a three point rear shock tower bar for use with the coilover setup. It will mount to the shock tops of course, and the lower bars will meet at the center of the trunk floor, between the shock towers. This will help strengthen the shock towers, and absorb some of the upward force from the springs.
 

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Another mounting point you could consider is the ones for the rear seat latches. Make the bar a 5 point in that case and you have that much more support. Just a thought.

An issue with repostitionint the shock, AND having a coilover setup to boot....will that interfere with the wheel, especially those of us who run 17x9 with ~275 tires?

Christian
 

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Discussion Starter #3
Racefiend said:
Another mounting point you could consider is the ones for the rear seat latches. Make the bar a 5 point in that case and you have that much more support. Just a thought.

An issue with repostitionint the shock, AND having a coilover setup to boot....will that interfere with the wheel, especially those of us who run 17x9 with ~275 tires?

Christian
I may use that idea...if it's cost effective to add the two extra mount points. We'll see if it's necessary. As for clearance on the coilovers. I have 16x8.5 Epsilons, with 245 tires, and it clears just fine. Do you have 17x9's Christian? If so, maybe you can come by and test fit it when I do the first prototype. Unless someone wants to donate a rim for me to use as a fitment tool. I'll take some pics of things as I work....if you catch anything I don't, constructive criticism is always welcome.
 

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Well, I have the Braid rims on the way..should be here shortly. If you need a test supra I'd be happy to use mine for test fitting. Let me know how things go.

Christian
 

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sounds good Christian..I'll be in contact with you as things progress. I'm trying to get prototypes done by late may/early june. If all goes well...production will begin before summer is over.
 

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Did this thread just die?

Whats the progress?

Am in need of some kind of adjustment for the rear. Cantilever coilovers sounded like a winner, what happeneD?


Thanks,
mitch
 

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i have been waiting for that cantilever setup for ever now, and it seems too complicated to happen.

still dreaming though
 

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I would also like to try mounting coil overs where our stock rear spring resides. I have an idea.
 

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as for reading some import magazines I have encounterd on the new 350Z coilover set-up from greddy and it uses the same identical rear trailing arm set-up on our cars and they use a adjusting collar on the bottom and the spring is on the top... same as the picture above
 

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I like the idea.. "Get hur done!" and get back to us and give us your virdict. I so need Camber adjustment in the rear..Damn ST Springs...



Thanks,
Mitch
 

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This is interesting that it has come up again.

I have fitted Koni Yellows on my Mk2, and to do this, I used MA70 rear shocks with a rod end bearing to mount it on the stock lower shock mount.

Here you can see a pic with my 17x8" rims with +6 offset (and with a spacer that will be removed for these rims - spacer was fitted for other rims)



The MA70 rear shocks have a platform to mount the rear spring, so it should be pretty easy to adapt them to take rear coil over springs without making mounts !!! They can be seen through the wheel in this pic.



I'll have to have a look in teh shed over the weekend. Will definitely have to have a good thing about approriate bracing though.

What sort of spring rates would be the best ? I'll do some calcs based on the differeing leverage length for the springs that I have in the standrad position.

Cheers

Michael B
 

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The iffy part about that would be the stress levels on the mounting points of the shock. The bottom of the shock is only held to the arm by the end of that bolt. I doubt it could take the load of the car all on it's own. Most likely it would bend very quickly. A quick fix would be to weld a square frame onto the arm to fit the bottom of the shock. The top is also questionable, being that it's thin cone shaped metal with little bracing. it would work for up/down loads, but be rather weak for side to side loads.
 

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Here's the solution (sorta), I posted this awhile back. Never contacted these guys at the time and now they're not making stuff anymore :(

The spring stays in the same place so no reinforcement/body mods are neccesary = GOOD.

This is similar to the other posted adjustable perch but for larger diameter springs. These should fit our stock springs, I've taken rough measurements of the Volvo springs for comparison.



http://www.mvpvolvo.com/
 
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