View Single Post
winders winders is offline
winders's Avatar
Join Date: Oct 2010
Location: San Martin, CA
Posts: 3,801
Originally Posted by panzerfaust View Post

when lower the car significantly the roll center goes subterranean, not really what u want. in effect reduces the resistance to roll.

also you may lose camber gain with a drastically dropped car on stock geometry not design to run that low... not that there is a lot with the standard 911 McPherson geo anyhow.

i believe these are the two main fixes for drop spindles .

in a nutshell, drop spindles enable the a drastically lowered car to get its RC back closer to the stock location . typically this means the lower suspension arm is near horizontal along the ground plane keeping the IC up above the ground (glancing at a factory drawings shows angle to move the IC just a tad up).

little correction on your comment above, yes all things being equal it will either change the angle of the suspension arm if you shoot for the same stock ride height or change the CG if the lower arm is in the same location. with raise spindles you cant have both were it once was and thats the whole point of it right?

bumpsteer does not not always get better with raised spindles by itself (us old alfa guys call it drop spindles cuz it drops the car). it does reduce the lateral displacement of the wheel/hub/steering arm which may help when a car is lowered without DS. but its not nearly enough.

too minimize bumpsteer the steering tie rods should be near parallel with the lower arm if you draw a line between the inner pick up and the outer ball joint. when you add raised spindles this relationship changes by splaying outer end of the steering tie rod out further than the inners in front view. Hence the value of a bumpsteer kit bring it back down.

now who will be a first to offer a drop spindle with the associate relocated shorten steering arms and possibly a steering rack displacement feature? this would eliminate the need for a bumpsteer kit and have faster steering response . guys can slam their cars with smaller 15inch wheels with the RC in the right place and have a quicker steering ratio in one full swoop. :-)

respectfully pf
The spindles are not dropped. They are raised on the strut body. Yes, I see you call that out...but it confuses the situation when you use incorrect terminology.
Scott Winders
PCA GT-3R #3
Old 05-31-2017, 04:46 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #29 (permalink)