SoR

iTrader: (19)

Guys, I basically need some guidance.
I understand the suspension basics but after installing my coilovers (after 3yrs on stock suspension) I now realize that in real life it's not as simple as I thought it would be
After playing a bit with ride height and then before putting everything in place, I tried to secure my spring perches (spring preload) and accidentaly moved one of them and then realized that I don't even know if preload is even set properly.

I understand that I need to take my car to get it corner weighted and aligned because without scales/computers it's just guesswork but I'd still like to understand how preload plays a role in the whole corner-weighting setup, how you should change it and when they do corner weight, what are all things they actually change, adjust and most importantly why since I thought that you only play with height on different corners and leave preload at a fixed number.
What I ended up doing is taking measuring tape and measuring the distance from the tower mount to the end of spring perches, from preches to the bottom lock-perch (height) and making sure both rear ones (left/right) are the same and then doing the same for the fronts but not taking numbers from the rear ones since spring lenght is different etc.

I couldn't find anything on the Internet really, at least nothing usable.
Is there a book which covers modern coilovers along with other suspension tuning? Most of the articles I found online speak only of the older/cheaper models where your ride height was adjusted by changing spring preload.
Thanks

Profoxcg

iTrader: (9)

I am subscribing to see what I can learn but,

Typically you lower ONE end of the car - either the front or the rear - (typically the front) to transfer more weight faster to that end while entering or exiting a corner.

I am not sure about cornering weighting but that just sounds like a fancy aligment job... doenst necessarily affect the ride height but perhaps how much preload each corner has so accomplish a more "neutral" chassis and CG.

I just got some coil over (buddy clubs race specs) I have yet to install them - which kind did you get? how do you like them?

PS. I've had megans on my EP3 2005 civic si and i love them ! I took the car to autox with them and they were great, the rebound adjustments really help.

SoR

iTrader: (19)

Wow 44 views and no replies. I'd hate to buy Carroll Smith's book(s) and not find what I'm looking for.
I got the Megan track series (small budged). It seems I'll have to roll the bumper in the back or maybe raise the car a centimeter or so.. my 255s hit the top of the fender, wonder what the camber is now..

nothere

iTrader: (23)

corner weight, you try to get the right front and left rear to weigh the same as the left front and right rear. you do this by adjusting ride height plus or minus in all four corners. you end up with a car that is not exactly equal left to right(side) but not typically visibly out of level.
as far as i know preload is a guess at corner weighing?

the real fun is adjusting bump and rebound(if you have two knobs).
have fun, its a learning experience.

read, good book to start with
"High Performance Handling" Handook by Don Alexander

SoR

iTrader: (19)

Unfortunately, for $900 you don't get 2 knobs
It seems setup will be more expensive than the coilovers themselves
I just hope they last until I can afford Vishnu Ohlins.

nothere

iTrader: (23)

corner weighting can cost some money . an alignment is crucial, have them set toe and camber too. the car does not come "good" from the factory. you can get one of those lifetime alignments, pretty good deal if you play with camber.

with the one knob your work is much easier! just turn it till it does something you don't like.

Noob4life

What coilovers do you have? Are you only able to adjust height via the spring perches, or do you have an adjustable lower mount?

if you have the latter, you should ONLY be using the adjustable lower mount to adjust height, thats the big benefit there - adjust your height, don't lose stroke.

Corner balancing is not necessary for a street car, but can be immensely helpeful for a track car. Its a potentially expensive proess, and not something you half-***. Cornerbalancing will result in a car that sits unevenly at each corner, more often than not. Preload is not a step or method involved in cornerbalancing, its a concept that belongs in the realm of two-wheel motorsports more so than 4 wheels and something you can forget about for your application.

Alignment is important for any car, and anytime you adjust ride height the an alignment should be performed. Also not something you half-***.

Cornerbalancing and alignment are two completely seperate processes, although an alignment should be performed after cornerweighting is performed, obviously. Cornerbalancing is *not* a substitute or alternative to getting an alignment, and vice versa.
If you're just looking for a level ride height, simply measure from the jacking points to the ground and make sure you're on a flat surface, very simple. If you're super ****, place a balast in the driver's seat equal to your weight to simulate the way the car would sit with you in it.

There's no book that covers "modern" coilovers or supsension or tuning because it does not take a book to cover something like that. The basic concepts and principles of suspension do not change, and if you're willing to take the time to learn, there are plenty of reliable sources of information out there already. RCVD (Race Car Vehicle Dynamics) is a heavy read but will cover just about anything and everything and provide you a mathematical basis to support the content. There's much lighter material out there as well, like Tune to Win by Carroll Smith, but if you're just looking to get at the more practical concepts then you just need to browse the internet a little more and you need to know what questions, not just "how do I tune a suspension?"

dogfacker

iTrader: (3)

don't really like the Megan or D2 style coilover, one setting for differen't car. try the HKS or Cusco, you will love it.

Slowride

iTrader: (3)

See:

http://farnorthracing.com/autocross_secrets.html

Especially:

http://www.wincom.net/trog/autocross_secrets5.html (suspension)
http://www.wincom.net/trog/autocross_secrets6.html (shocks)
http://www.wincom.net/trog/autocross_secrets11.html (corner weighting)

SHhhhh

iTrader: (73)

any updates? I am running the BC Racing coilovers and are nice for the street. Still trying to dial them in though.

how many "clicks" do you have yours set at for the street? i am trying to find a good balance between ride quality and handling.

my car has a tendency to oversteer more than the stock suspension, which is fun, but would like a more neutral balance.

matyb

iTrader: (1)

very good read

EvImVictim

iTrader: (11)

This should be a sticky. Really good stuff!

texasevo

iTrader: (5)

After i got my coilovers i needed a camber kit that was $100. My car couldnt be aligned properly without it.

hokiruu

iTrader: (19)

Yes that DG link Slowride posted is one of my favorite resources. In there he also debunks myths about "knobs and clicks". Referring to "The HKS or Cusco" is not very helpful, especially because it wasn't stated which ones, but also because he already has coilovers and it sounds like he wants to try to get the most out of them.

I'm sure you can find an experienced racer or tuner near you in NJ who can help you get your coilovers dialed in. You might try looking into your local SCCA chapter for references.

GTLocke13

iTrader: (1)

As someone who's just beginning to understand this stuff, this is how I think of it:

You know when you go to dinner and have a table that rocks back and forth because one leg is shorter than the other three? Cars do the same thing. Three points define a plane. You can define a plane based on the center point of any three wheels on your car. The fourth wheel's center point won't be in the same plane as the other three because the tape measure you used to set up your coilovers isn't that accurate, not to mention the fact that your frame is most likely not straight to better than about 1/8" (guessing on that one). Because the position of the wheels is actually defined by the ground, this non-planarity manifests itself in weight variations as opposed to differences in distance. Cornerweighting is an attempt to get all four wheels in the same "plane" by equalizing the weight carried by the individual wheels as much as possible. It's kind of like folding up a napkin and putting it under the table to keep it from rocking.

Alignment is just adjusting the angles of each wheel relative to the ground (camber) the centerline of the car (toe) and the axis of wheel rotation (caster).