Shocks, either reg shocks only or coil overs, can be mounted vertically or at a angle. By mounting at angle the shock is no longer working at the listed ratings. Speedway use to have a chart showing that the angle decreases the shocks strength. That being said most shocks are mounted at a slight angle. Usually the angle is set by the available space for the shocks.
Yes and no. On a solid axle, mounting them with the upper ends inboard from the lowers helps control body roll.
Here are a few items that have been posted in other threads that may amount to some useful info all in place for you check out.
A few questions arise: surely the correction factors should equal the cosine of the angle from vertical? The factors given in the respective tables differ from one another, and both differ from the cosine of the angle in question. I should rather expect: 10° .985 15° .966 20° .940 25° .906 30° .866 Importantly, this applies only where the force to be resisted is vertical, e.g. a conventional axle. If there is a linkage of any sort between the wheels and the springs, e.g. (but not only) any kind of independent suspension, it is necessary to figure out the direction of the force where it acts on the spring, and measure the installation angle from that angle. (The .pdf file shows a set-up featuring triangulated 4-links and a Watts linkage, which should generate a conflict of rotations, even though the angled links' angle is insufficient to provide adequate lateral location on their own. Would parallel links not be better here?)
Tilting the coil-overs over also allows use of a shorter coil-over, albeit a stiffer one. For instance, if one tilts a damper or coil-over 45°, one needs only 4⅛" of travel at the damper or coil-over to achieve 6" of travel at the axle. This makes for a more compact and possibly cleaner installation. The downside is that the effective angle decreases with travel, leading to falling-rate spring characteristics. It might be worth considering using rising-rate springs with a fairly severe rate of increase, to compensate and then some.
Dawie and Fifty v8 Moving a shock inboard from the wheel decreases the travel of the shock. My question is at what angle does the shock stop working because the shaft is flexing. I am guessing it would have to be layed over pretty far?
What I was thinking.... Makes me wonder if they were trying to show a few different things on those drawings, and we didn't see all of it? Or maybe it was just another one of those "experts" on the internet.
I'd go with gimpyshotrods on this. useing straight up ad down as 90 degrees, angleing them in at the top 20 degrees or to 70 degrees is what I did with mine and they work great, very stable in corners and good ride control overall.
As long as the damper or coil-over is effectively hinged at both ends there are only compression and tension forces on the shaft, and nothing to cause it to flex. The position of the spring/damper in relation to the track will decrease travel in roll but not in two-wheel bounce. That is, when both wheels on an axle move the same way relative to the body, it doesn't matter where the springs/dampers are on the width of the axle. Tilting the springs over will decrease the effective spring rate, as explained above, moreso in roll than in bounce. The distance between the spring mountings to the axle is called spring base. A conventional solid axle will always have a spring base:track ratio of less than 1. This is a real shortcoming of conventional axle set-ups, and one of the few valid advantages of independent suspensions. With a bit of cleverness, however, it is possible to devise solid-axle suspension with a spring base:track ratio considerably higher than 1. The challenge is to make it simple.