Difference between revisions of "Suspension"

Revision as of 17:05, 27 February 2012

Back up to Main Page.

Shocks

Shaikh gets to take all my money. I've ordered a full double adjustable setup from him, but it's not going to be ready until mid to late april, so until then he's making me a stopgap setup on stock HDs to get by, which he'll buy back when he finishes the DA setup.

Springs

Starting with 700/450, and buying spring rubbers to allow tuning on the fly.

According to Shaikh, the stock spring motion ratios are 0.66 F and 0.72 R. That's spring travel / wheel travel.

Since we will be designing new control arms, we will need to pay attention to wheel rates, not just spring rates. Wheel Rate = Spring Rate * (Motion Ratio)^2. Changes in CG, track width, roll center, desired ride frequency, sway-bar stiffness, and David's calorie intake will all affect this decision.

Swaybars

Front: Starting with the Racing Beat tubular adjustable front 90-93 bar. Rear: Trying to stay without a bar for power application reasons.

Control Arms

Currently Stock. Presumably dealing with this as part of the Uprights project.

V8Roadster sells a full set of replacement arms. They're 1800$ for the set.

EPMiata sells upper control arms, front and rear. 284$ for a rear set, 445$ for a front set.

TC Sportline also sells upper control arms, 299$ a set front, 219$ a set rear. They look pretty sketchy though.

Spindles

Currently ABS stock spindles all around. Need to remove dust covers for now. Working on creating drop spindles with the Uprights project.

Bushings

The control arm connections will all be changed to solid heim components.

What else are we going to change? Subframe bushings are allowed to be changed (16.1.H.)

Steering Rack

Swapping to an NB power steering rack. Incompatible with the NA pump/lines, so ordering NB pump and lines to put on later. The bolts are also bigger/different from the NA rack to subframe bolts, so trying to find those as well...

Solo Rules

16.1.F.1. Steering components, including the steering rack and/or box, tie rods, idler arms, power assist devices, and related components, may be replaced, added, moved, or removed. The steering column, within the passenger compartment, is specifically excluded from this allowance.

Subframes

Front

Car currently has the NB subframe on it.

Front subframe got an upgrade in 1999 to revise the suspension pickup points for slightly better roll centers. Currently measuring to see what the actual differences are...

There is a new SSM rule for 2012 that allows the creation of custom front subframes, but suspension pickup points have to stay identical to stock and the weight has to be at least that of the stock piece it's replacing, so I'm not sure it's useful for us.

Rear

Rear subframe has to stay stock. To my knowledge the same subframe was used all the way through the 90-05 range.

Solo Rules

Section 16.1.E of the Solo rules states:

"Suspension components are unrestricted as long as they use the original attachment points. For the purposes of this rule, “suspension” is defined as any item that is designed to move when a wheel is deflected vertically. This includes shocks and struts, control arms, steering knuckles, uprights, etc., but not tie rods, steering racks, and subframes. In addition, shock absorber/strut upper mounts are to be considered suspension components."

This allows the use of fully custom uprights and A-arms.