gtivr4 wrote:
This was done to accommodate a LONGER shock actually. They have about 5.5" of travel and currently have 200lbs springs, so they wouldn't fit in the 'book' location. I guess moving the upper mount further inboard would solve most of the issues. And no, I haven't done any calculations yet.
What is the calculation anyways? Lets assume that the mount on the axle is where I drew it, and the upper mount is moved inwards (so they are in line). Lets also assume that they are at 10º from the side. So a total of 10º of angle... 200lbs springs (although thats easily changed). Anything else needed to make the calculation?
Sorry, saw the remote reservoir and made an assumption.
The 10 deg in itself doesn't hurt too much, degrading installation ratio by cos(10), about a 2.5% decrease which is fine.
The problem is that the shocks are mounted roughly half way between the tire contact patch and axle centerline. Half way means that's your installation ratio, so you need four times the spring rate to give a specific wheel rate.
Interestingly,
this is only true in a one-wheel bump. When hitting a dip in the road that compresses both shocks at the same time, the installation ratio is 1:1. It's going to cause handling issues because it'll be stiff when hitting bumps common to both shocks, but four times softer when hitting one-wheel bumps or cornering.
Think of the extreme case, moving the shocks so far inboard that they end up at the center of the axle. When hitting common bumps everything's fine, but when hitting a one-wheel bump or cornering, the car has zero roll resistance amd will fall over!
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