New pics after some simple mods....
02-14-2005, 01:35 PM
#31
Racer
Thread Starter
go lower!
i like the look but my front bumper is having to deal with my steepish curb/driveway. the black plastic cover has ripped off!
This car will see a lot of track use, so the nice thing about the coilovers is the ability to raise and lower/realign easily. Helps to have access to an alignment machine, though!
02-15-2005, 12:30 PM
#34
Racer
Thread Starter
riotgear....I definitely recommend a well engineered coilover setup (PSS9 or H&R, or if you have some cash to burn and love track days - Moton Club Sports). The PSS9's have great, easy built-in adjustability, which is perfect for track days. The H&R's don't have that out of the box, but it still makes for an agressive street/track package with relatively easy ride height adjustability. My problem with springs-only is you're always "mixing and matching" spring/shock packages and you're never sure if you're really getting a system that's been specifically engineered/valved for your car, plus you get a static ride height that cannot be tailored to your preference.
02-16-2005, 12:17 PM
#35
Rennlist Member
SRL - how easy is it to adjust the ride on the PSS9s? How are they adjusted and does it require removing the wheels? Are there clicks or marks to help with the adjustments?
02-16-2005, 12:28 PM
#37
Racer
Thread Starter
The PSS9 comes with an adjustment **** that allows you 9 different damping settings. Most of the ones I've seen have the **** at the bottom of the shock. You shouldn't have to remove the wheel for damping adjustment but you definitely would for ride height adjustment, followed by an alignment (no alignment needed for damping-only adjustments).
02-16-2005, 12:31 PM
#38
To change the settings, it is somewhat a pain to do the fronts. The easiest way is to crank the wheel one way to give enough room. I have the caps on the fronts and you have to take those off to adjust them. In the rear it is under that foam shelf where the ecu is.
02-16-2005, 01:00 PM
#39
Rennlist Member
Am in that oft discussed pss9 vs x73 quagmire of decisions. And the ease of making damping adjustments ... well, that sounds great. 
Appreciate your input SPR, SLR, & C4S Surgeon!
Appreciate your input SPR, SLR, & C4S Surgeon!
02-16-2005, 02:35 PM
#41
Burning Brakes
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Carlos' answer is pretty good. Technically, bump steer is a change in toe while the suspension is loaded/unloaded. Normally, going over rises/dips in the road, both L/R wheels will experience the same toe changes and thus the forces will couteract eachother. It's when only one wheel hits a "bump" is the toe change not counteracted by the other side, and hence one wheel will be toe in/out and tend to steer/pull to one side. Hence, the term bump steer.
Changing suspension geometry/alignment can change the bump steer characteristics. Changing wheel width/offset/tire theoretically should not, but...
With tire/wheel changes, what happens is similar, and I don't know if there is a term for it. Basically, there is a theoretical/mathematical axis about which the suspension moves and rotates. For out strut-equipped cars, it roughly follows the strut housing itself. If you're visualizing this, the effective tire contact patch (under various conditions) should be in-line with this axis. If it is not, there is a torque that will try to rotate the wheel/tire about this axis.
Similar to toe changes, it usually counteracts L/R, but going over bumps will cause a similar effect as toe changes. The bad thing whether counteracted or not is that too much can cause accelerated wheel bearing load/wear. I can definitely notice it on my bigger wheels with more offset. Also, the stiffer, lower profile tires will move that effective contact patch out from the center (opposite of what you would imagine of a little, skinny tire).
Disclaimer: I am not a suspension engineer, but this is pretty close
Changing suspension geometry/alignment can change the bump steer characteristics. Changing wheel width/offset/tire theoretically should not, but...
With tire/wheel changes, what happens is similar, and I don't know if there is a term for it. Basically, there is a theoretical/mathematical axis about which the suspension moves and rotates. For out strut-equipped cars, it roughly follows the strut housing itself. If you're visualizing this, the effective tire contact patch (under various conditions) should be in-line with this axis. If it is not, there is a torque that will try to rotate the wheel/tire about this axis.
Similar to toe changes, it usually counteracts L/R, but going over bumps will cause a similar effect as toe changes. The bad thing whether counteracted or not is that too much can cause accelerated wheel bearing load/wear. I can definitely notice it on my bigger wheels with more offset. Also, the stiffer, lower profile tires will move that effective contact patch out from the center (opposite of what you would imagine of a little, skinny tire).
Disclaimer: I am not a suspension engineer, but this is pretty close
