Mid perch – not for lifting, but to aid with added front end mass

boarder1995 said:

So this has been beaten to death? Sorry guys... lack of historical perspective on my part.

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boarder1995 said:

First, I’d like to clear up one misconception that has been bugging me…
The moving up of the spring support ring (moving down of the shock) does NOT add pre-load to the spring. This is commonly referenced as to why the ride is stiffer – because there’s more preload in the spring. This is incorrect. The spring maintains its state of loading which is caused by the mass of the truck (fixed in this argument). It’s not getting compressed anymore. It’s merely moving the shock body and lower mount down, thus moving the truck up. What’s causing the increased harshness of the front end? First, you’re now in a different point of the shock’s stroke, which with the valving we have might put us in a harsher point of travel in the shock (maybe, maybe not? I haven’t disassembled this shock). Additionally, we’ve increased the angle of the A-arms in our suspension to a less compliant, steeper angle. The optimal nominal angle for A-arms is straight out horizontal. Picture them in a near vertical down fully drooped position – that’d be a very non-compliant angle. The steeper the angle, the harsher at the ride will be if that’s the nominal geometry. With just a couple inches movement down of the A-arms by going to mid-perch, I can’t imagine this would make a huge change in feeling.

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LEEHWCAP said:

I'd like to just say "search" like everyone else but the statement above is not correct. It would be if the coilover at bottom perch had zero preload and the spring just rattled around when the suspension was at full droop. In that scenario you would just be adjusting the coilover to a taller position but in reality there is preload on the spring/shock even at bottom bottom perch, so moving that spring/strut to middle or top perch is squeezing the spring more resulting in more "preload". And that added preload is why it rides stiffer at mid perch. Also why I went with progressive springs to keep my softer ride.

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