1st gen Fully Adjustable Coilover Rear (minus camber)
10-16-07, 03:48 PM
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1st gen Fully Adjustable Coilover Rear (minus camber)
anywho, i've been working on this for awhile now that its pretty m uch 100% done, i figured i would post it up since i said i would back 6-8 months ago when i posted that i am doing it.
to start with I know that they setup is still, thats what i want, we'll see how it works in the spring
btw... that is a 8" Toyota rear end (axles are about twice the size of stock axles ) The coilovers are 6kg/mm (or 335lbs/in if you need the conversion) fully adjustable for height, and dampening (obviously not camber 
)
The front setup that im working on as of now for the front is 8kg/mm (450lbs/in) and fully camber, height, damping adjustable. the setup will consist of 84-85 rx7 front strut tubes mated to similar front coilover setup, an attached to it will be the great respeed big brake setup with a 5 lug setup
anywho, if you feel the need to ask a question on the setup, feel free.
~Nick
to start with I know that they setup is still, thats what i want, we'll see how it works in the spring
btw... that is a 8" Toyota rear end (axles are about twice the size of stock axles
) The coilovers are 6kg/mm (or 335lbs/in if you need the conversion) fully adjustable for height, and dampening (obviously not camber ) The front setup that im working on as of now for the front is 8kg/mm (450lbs/in) and fully camber, height, damping adjustable. the setup will consist of 84-85 rx7 front strut tubes mated to similar front coilover setup, an attached to it will be the great respeed big brake setup with a 5 lug setup
anywho, if you feel the need to ask a question on the setup, feel free.
~Nick
10-16-07, 05:34 PM
#3
Looks good. My only comment, from an engineering standpoint, would be to tie the top of the coilovers back down to the frame rails. Since you removed the strut tower, which is a major structural part, you will need to recreate it's properties. The long diagonal bar that the top is now tied to will have some minor flexural issues.
10-16-07, 06:35 PM
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Looks good. My only comment, from an engineering standpoint, would be to tie the top of the coilovers back down to the frame rails. Since you removed the strut tower, which is a major structural part, you will need to recreate it's properties. The long diagonal bar that the top is now tied to will have some minor flexural issues.
an example from real life
ground control camber plates, 1/8" aluminum, these fail by breaking. aluminum doesnt bend. what kind of force is there to break 1/8" aluminum? especially since its connected to the shock!
now this is in a racing environment, and its fairly rare, but thats the kind of force that the suspension encounters
10-16-07, 08:44 PM
#7
Looks good. My only comment, from an engineering standpoint, would be to tie the top of the coilovers back down to the frame rails. Since you removed the strut tower, which is a major structural part, you will need to recreate it's properties. The long diagonal bar that the top is now tied to will have some minor flexural issues.
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10-16-07, 08:44 PM
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Yeah I agree, I would have modified the stock strut tower to fit the Coil-Overs in, the car had them for a reason... Now the roll cage is both supporting the frame of the car and your suspension... I doubt it, but if you hit a very nasty turn or bump those mounts might warp or break.
10-16-07, 10:11 PM
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10-16-07, 11:27 PM
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well to be honest the setup is not 100% quite yet but structually its pretty much all there, i will be making a welded in strut brace that goes across the two NEW strut towers. the two bars that you see that hold the coilover up will be gusseted in to increase its strength, so added gussets and a solid strut bar, should by far be plenty strong for this light of a car.
DemonSpawn the rear strut tower setup was almost an inch too small in diameter so it would have needed to be cut nearly completely out anyways to make it work...
mikewoodkozar I used the solid because completely fabbing up a IRS setup would have taken alot more time, and would have been MUCH MUCH more difficult to figure out to work properly
aws140 Nope no cutting of the rear axle, that is what you see (besides the mounts) underneath a stock toyota mini truck (91-93 toyota pickup i believe?)
dantheman I stayed with the stock watts setup because mazda did alot of engineering, and the car can be made to handle VERY well with it, so why change something thats been proven time and time again?
Also on another note, this car Is being designed to be VERY versatile from AutoX, Drift, to drag. This car is being built for it all. will it be the fastest drag car...no. will it be the best drift or autox car...no. But i guarauntee it will be faster that 90% of the cars that do those things though, and that in all is enough to say i've succeeded in building a car that can compete in anything and be successful.
DemonSpawn the rear strut tower setup was almost an inch too small in diameter so it would have needed to be cut nearly completely out anyways to make it work...
mikewoodkozar I used the solid because completely fabbing up a IRS setup would have taken alot more time, and would have been MUCH MUCH more difficult to figure out to work properly
aws140 Nope no cutting of the rear axle, that is what you see (besides the mounts) underneath a stock toyota mini truck (91-93 toyota pickup i believe?)
dantheman I stayed with the stock watts setup because mazda did alot of engineering, and the car can be made to handle VERY well with it, so why change something thats been proven time and time again?
Also on another note, this car Is being designed to be VERY versatile from AutoX, Drift, to drag. This car is being built for it all. will it be the fastest drag car...no. will it be the best drift or autox car...no. But i guarauntee it will be faster that 90% of the cars that do those things though, and that in all is enough to say i've succeeded in building a car that can compete in anything and be successful.
10-16-07, 11:31 PM
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btw...thanks everyone for your comments and questions, im just here to try something different, and hopefully learn and have everyone else learn stuff that is possible, but not thought of for our cars.
also thanks trochoid you always have something useful to say, and me and you are thinking along the same lines, i also agree that the car is yet stable enough to throw on the road quite yet without some more tweaking of its mounts. we'll also find out how it holds up in the long run as going from autoX (with R-comp tires) to the drags with the 8.5x26 et slicks, will certainly put my fab work to the test.
also thanks trochoid you always have something useful to say, and me and you are thinking along the same lines, i also agree that the car is yet stable enough to throw on the road quite yet without some more tweaking of its mounts. we'll also find out how it holds up in the long run as going from autoX (with R-comp tires) to the drags with the 8.5x26 et slicks, will certainly put my fab work to the test.
10-16-07, 11:41 PM
#16
it's always nice to see someone changing the rear suspesion design!
no offense but the 1st gen watts link is one of the worst I've ever seen. it's been proven to be bad geometry. waaaaayyyy too high and offset to one side. the center pivot bends and breaks. has everything wrong with it. mazda went with a quick solution for that.
and the upper trailing links are short and angled, those are bad too. doing a real 4 link with more adjustability would be in your best interest, especially for drag so you can crank up the anti-squat. for auto-x I think you're bumped all the way up to MOD class due to the rear coilovers which also moved the upper suspension pickup point.
the mounting for the coilover tops isn't the best, it needs some work. i'd also box in the lower brackets for the coilovers.
best of luck, keep us updated. and above all have FUN.
no offense but the 1st gen watts link is one of the worst I've ever seen. it's been proven to be bad geometry. waaaaayyyy too high and offset to one side. the center pivot bends and breaks. has everything wrong with it. mazda went with a quick solution for that.
and the upper trailing links are short and angled, those are bad too. doing a real 4 link with more adjustability would be in your best interest, especially for drag so you can crank up the anti-squat. for auto-x I think you're bumped all the way up to MOD class due to the rear coilovers which also moved the upper suspension pickup point.
the mounting for the coilover tops isn't the best, it needs some work. i'd also box in the lower brackets for the coilovers.
best of luck, keep us updated. and above all have FUN.
10-17-07, 12:34 AM
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it's always nice to see someone changing the rear suspesion design!
no offense but the 1st gen watts link is one of the worst I've ever seen. it's been proven to be bad geometry. waaaaayyyy too high and offset to one side. the center pivot bends and breaks. has everything wrong with it. mazda went with a quick solution for that.
and the upper trailing links are short and angled, those are bad too. doing a real 4 link with more adjustability would be in your best interest, especially for drag so you can crank up the anti-squat. for auto-x I think you're bumped all the way up to MOD class due to the rear coilovers which also moved the upper suspension pickup point.
the mounting for the coilover tops isn't the best, it needs some work. i'd also box in the lower brackets for the coilovers.
best of luck, keep us updated. and above all have FUN.
no offense but the 1st gen watts link is one of the worst I've ever seen. it's been proven to be bad geometry. waaaaayyyy too high and offset to one side. the center pivot bends and breaks. has everything wrong with it. mazda went with a quick solution for that.
and the upper trailing links are short and angled, those are bad too. doing a real 4 link with more adjustability would be in your best interest, especially for drag so you can crank up the anti-squat. for auto-x I think you're bumped all the way up to MOD class due to the rear coilovers which also moved the upper suspension pickup point.
the mounting for the coilover tops isn't the best, it needs some work. i'd also box in the lower brackets for the coilovers.
best of luck, keep us updated. and above all have FUN.
btw i love your REPU and your 7 looks pretty damn nice also good job!
P.S, i only have around 950 bucks into the rear suspension which i think is pretty good for how tough it should be. especially with the dampening and height adjustablity.
10-17-07, 12:35 AM
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oh...and yes i will be in mod class, we'll see how it performs once i get the front setup done, and get the full poly setup and new RB swap bars in 
should be basically like a rock, which i suppose is good and bad...
should be basically like a rock, which i suppose is good and bad...
10-17-07, 12:12 PM
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If you look under the rear of almost any racing RX7, you will find a 3link/panhard setup. I recently purchased one myself, but haven't installed it yet. The overall design looks pretty simple, and I've heard of people fabbing their own. With what I've seen of your skills so far, it shouldn't be much of a job for you. Nice work so far.
I do have one question though. You could have achieved adjustable dampening with Illumina shocks, adjustable ride height with adjustable collars (which I just installed and love), and had about 700 bucks left over for the 3link/panhard setup (which only runs about 300 if I remember right). Were you not aware of this, or did you just want to do your own thing? I just ask, because with the setup I just mentioned you could have run in Street Prepared rather than mod....
I do have one question though. You could have achieved adjustable dampening with Illumina shocks, adjustable ride height with adjustable collars (which I just installed and love), and had about 700 bucks left over for the 3link/panhard setup (which only runs about 300 if I remember right). Were you not aware of this, or did you just want to do your own thing? I just ask, because with the setup I just mentioned you could have run in Street Prepared rather than mod....
10-17-07, 12:35 PM
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^^^ yes i did know of this option, however since this car WILL be in every type of racing i needed the suspension to be as interchangeable as possible, the 3rd member on this can easily swap out gears ect, and is alot more solid than the 1st gen setups. imagine this kinda as a grannys rear end swap but without the stock spring and strut setup. (which grannys rear swaps cost about as much as mine in the long run). Since The rear setup is (240sx coilovers) i can also substitute stock 240 spring/strut combo for a really soft rear suspension for drag racing. Like i said this setup is setup to be versatile.
~Nick
btw, thanks for the comments on the work Kentetsu
~Nick
btw, thanks for the comments on the work Kentetsu
10-17-07, 03:52 PM
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to be honest the shop that all this work is being done at does rock crawlers (I.E. constant drops from 5-15ft, roll overs, constand load and preloading, ect) and there mounts have never broken. so i would feel safe to say my will hold up