pondering the use of coil over shocks...

[oldschoolimport]

I have a ton of leftover honda parts laying around, and figured I might could use some of them. the axle is from an 87 integra, and the shocks and coils are from the rear of an 02 civic Si. with the shock mount at a 45 degree angle under the axle, rather than above it (roughly where the bottom of the shock is in the pic), the top of the spring will be about at the height of the wheel, including the mount. the upper mount/spring perch will be placed inside the frame rail, to keep from adding additional height. I would use a trailing arm, with triangulation for axle centering.

I halfway mocked up how the shock will sit on the drop axle. am I crazy for not going traditional with leafs?

[madjack]

osi, the only concern I would have, would be that the setup would be "over suspended" and result in a rough ride for the TD...I have thought about the same setup but was looking at using motorcycle coil overs to get a proper suspension rating for the weight of the TD......
madjack

[oldschoolimport]

I've considered that. the 02 civic Si is about 2800 pounds total, with the majority up front. the rear set-up is soft on the car. considering about 1200 pounds for the rear weight percentage, that puts me close to the weight of a tear, especially after I pack it real tightly.

[asianflava]

I don't remember exactly but doesn't the 86-88 teg have some kind of torsion bar inside the axle tube?

I remember looking under my CRX wondering where the rear sway bar was after reading that they were supposed to have front and rear sway bars. I know that they had coil springs in the back but I think they considered that torsion bar as a sway bar.

02 Si was 2800lbs? My CRX was only ~1800lbs which is only a few hundred pounds more than my tear when fully loaded. Maybe CRX HF springs/shock would be better suited, plus they'd bolt up to the teg axle. People use Dodge Caravan axles all the time so I don't see why this wouldn't work.

Good to see another oldschoolimport fan. I have my EF as a toy/project.

[oldschoolimport]

cool! I have an 86 Si for track days. are pics of the EF posted on here anywhere? I recently helped my cousin with a 99 GSR swap in an EF Si.

the axle has an internal torsion bar on the right side, along with a swing bearing. the internal torsion bar has been removed. I will be mounting the axle tube to the new arms, rather than utilizing the swing bearing mount, so there will be no twist allowed. the 86-89 teg rear end is the same as the 84-87 civic/crx, except it had rear disc brakes.

the 02 Si shock eyelet is the same size as the old integra shock eyelet. if its over-sprung, I have springs from the old integra I can use, they will just need to be cut down. the main component for this to work is the short shock from the 02 civic.

you read it right, the new civics are over-weight pigs. my 86 weighs 1000 pounds less than my 02.

[starleen2]

I say . . . if you have the parts already, if they cost you very little, and you have the time without spending extra $$$ - then go for it. other than than that I see very little benefit. it's a good concept, but you just don't see very many builders doing it because its benefits are marginal compared to the costs involved

[asianflava]

You may want to keep the panhard bar to prevent any side to side play on the axle.

[oldschoolimport]

rather than the panhard, I was going to triangulate a bar from the front of the trailing arm, close to the mount, back to axle tube on the opposite side. that way, the axle stays centered without the side to side shift of the panhard, and it eliminates having to fab up a panhard mount.

this arrangement is all free, versus having to buy leafs, axle, hubs, and mounts. plus I have 4 sets of honda wheels and tires that I can gradually work thru. that will eliminate the need to carry an additional spare, since the one in the tow vehicle will work on the trailer.

[aggie79]

You might want to measure your what your ground clear will be with this setup and consider how this will look with your teardrop design. I wanted my teardrop to be "low slung" and am planning on about 12" of clearance. I don't know what size wheels & tires you have in your mockup, but it seems that you would have 18"-20" ground clearance which is on the tall side of things, even if you are going for the offroad look.

[oldschoolimport]

in the mock up, its 14" wheels and 195/60/14 tires. its looking to sit at about 14-15" to the bottom of the frame rail, depending if I run 14 or 15 inch wheels, and 60 series tires, with the upper spring mount sitting inside the frame rail.

[brian_bp]

rather than the panhard, I was going to triangulate a bar from the front of the trailing arm, close to the mount, back to axle tube on the opposite side. that way, the axle stays centered without the side to side shift of the panhard, and it eliminates having to fab up a panhard mount...

I understand the logic, but with the relatively small travel likely in this setup, and a good long panhard rod (compared to some other cars), I would not expect the lateral movement to be a big deal. I never found it a problem with our race-prepared 1985 CRX.

I would be inclined to use the original arms and panhard rod, personally.

[brian_bp]

You might want to measure your what your ground clear will be with this setup and consider how this will look with your teardrop design. I wanted my teardrop to be "low slung" and am planning on about 12" of clearance. I don't know what size wheels & tires you have in your mockup, but it seems that you would have 18"-20" ground clearance which is on the tall side of things, even if you are going for the offroad look.

Keep in mind that this is a dropped-beam axle design, although not normally dropped as much as it looks in the photo, because the axle tube is both below and behind the hub centre line in the stock installation (not directly below). The stock CRX floor is really high - too high for a teardrop - but that's controlled by the tops of the struts and packaging of other components, rather than the axle.

As I understand the plan, the struts are to be leaned rearward, and if the axle tube is rotated that way as well, it would end up as a big drop just as shown in the first photo... although that would prevent the use of the stock trailing arms as my previous post suggested.

[brian_bp]

...
the axle has an internal torsion bar on the right side, along with a swing bearing. the internal torsion bar has been removed. I will be mounting the axle tube to the new arms, rather than utilizing the swing bearing mount, so there will be no twist allowed...

Wow, that could be a lot of torque to apply to a tube which is not supposed to be loaded in torque at all. Many current suspension designs depend on a tube or beam twisting, but those forces are considered in the structural design. Why not leave the torsion bar in place and attach to the hub side of the swing bearing as originally designed?

[brian_bp]

I remember looking under my CRX wondering where the rear sway bar was after reading that they were supposed to have front and rear sway bars. I know that they had coil springs in the back but I think they considered that torsion bar as a sway bar.

Yes, that is the sway bar. It is loaded only in sway, not in equal compression of both sides; essentially, the trailing arms are the end links for the sway bar.

It is not easily changed for a stiffer bar, so my CRX has a conventional sway bar bolted on externally, in addition to the internal bar.

[brian_bp]

For the weight, when choosing springs, I suggest considering the normal loaded weight. The cars can be overly stiff for their weight when empty (especially the rear-light CRX), but are probably close to right with a typical load... and in a CRX the rear suspension takes the majority of the passenger load, plus all of the cargo.