I was looking at this link that depicts using an STI suspension with a 2" spacer to keep the stock ride height on a Forester XT. There are some roll calculations that I don't understand, and it really exposed my ignorance about suspension in general aside from smoothing out the bumps and keeping the car planted on the road.
I know this has been covered before, but I can't find it. What are 2-3 books that cover the basics of suspension geometry and setup?
Thank you in advance. I'm going to go buy some STI pink springs and try to figure out how to get a Koni insert into my housing.
Hasbro
Dork
2/17/12 11:27 p.m.
How To Make Your Car Handle, Puhn
Chassis Engineering, Herb
Adamshttp://www.motoiq.com/tech/the_ultimate_guide_to_suspension_handling.aspx
The Race and Rally Car Sourcebook, Allan Staniforth
Think Fast, Neil Roberts. I like his philosophy of avoiding interactions between parts of a system. He also gives the best, clearest description I've read of how damping adjustments affect the parts of a corner.
I think Carroll Smith's "Tune to Win" is vital reading, but can't recall off the top of my head whether it gives a suspension geometry overview...
Ah, it does, though my two caveats for him are that A) He dives in perhaps bit more deeply immediately than you might want for an introduction, and B) I can never shake the feeling that he's occasionally talking about things that apply more to pure race cars than production-based cars and doesn't necessarily point out when there's a distinction. That being said, I expect the overview is mostly applicable, and it's a generally terrific book.
Book 0: A big posterboard, some pencils, some tacks, and some cardboard. Construct full-scale or larger 2-D models of any suspension you're thinking about and move them thru the full range of travel. Won't take too long and you'll know what you're reading later.
Book 1: Tune to Win by Carroll Smith.
Book 2: Think Fast by Neil Roberts.
chaparral wrote:
Book 0: A big posterboard, some pencils, some tacks, and some cardboard. Construct full-scale or larger 2-D models of any suspension you're thinking about and move them thru the full range of travel. Won't take too long and you'll know what you're reading later.
Book 1: Tune to Win by Carroll Smith.
Book 2: Think Fast by Neil Roberts.
Book 0 is not a bad way to give yourself a good idea of what the books are trying to teach you. Conversely, go out to any car you have that has the wheels off and the springs and dampers out.. and move the suspension around by hand. (We all know you have at least one car around like that)
mad_machine wrote:
go out to any car you have that has the wheels off and the springs and dampers out.. and move the suspension around by hand. (We all know you have at least one car around like that)
Heh, I put it back together not long ago, but I did have a car like that for a while. I'm going to have another car like that, soon, too.
Book 3: Miliken's Race Car Vehicle Dynamics.
Itt seems to me that as long as the lower control arm is near the stock angle, then the roll center would be the same
The strut is functioning as it is supposed to .
The spacer is just making up for the differnce from the stock one.
Of course with the shorter strut there is less wheel travel.
mad_machine wrote:
chaparral wrote:
Book 0: A big posterboard, some pencils, some tacks, and some cardboard. Construct full-scale or larger 2-D models of any suspension you're thinking about and move them thru the full range of travel. Won't take too long and you'll know what you're reading later.
Book 1: Tune to Win by Carroll Smith.
Book 2: Think Fast by Neil Roberts.
Book 0 is not a bad way to give yourself a good idea of what the books are trying to teach you. Conversely, go out to any car you have that has the wheels off and the springs and dampers out.. and move the suspension around by hand. (We all know you have at least one car around like that)
I think it was Stanforth that used book zero as his "computer" before he had computers. I have done this. It is a lot cheaper and easier than Solidworks to figure out where everything will be when you can articulate with yarn.
93EXCivic wrote:
Book 3: Miliken's Race Car Vehicle Dynamics.
Although a great book @ $90 a copy it is over the top for someone wanting a basic (and even fairly advanced) understanding of suspensions. It provides valuable theoretical information but presents it in a very dry textbook way that requires a good understanding of suspension design and fairly advanced math to apply.
I like tune to win and competition car suspension buy Stantiforth as good moderate depth suspension books. The only topic they are deficient on is some advanced weight transfer stuff, Modern shock information, and ackerman theory (milikin misses on this as well making me think it simply isn't well understood).
nocones wrote:
93EXCivic wrote:
Book 3: Miliken's Race Car Vehicle Dynamics.
Although a great book @ $90 a copy it is over the top for someone wanting a basic (and even fairly advanced) understanding of suspensions. It provides valuable theoretical information but presents it in a very dry textbook way that requires a good understanding of suspension design and fairly advanced math to apply.
Second that. It's a great way to get in over your head and pissed off if you're not already familiar with vehicle dynamics. I'd definitely start with Tune to Win and Think Fast.
Thanks for all of the replies so far. I'm going to look for a few of these on the flea-bay and at the local used book shop.
I'll probably never design my own suspension or really modify anything beyond using off the shelf aftermarket pieces, but I hate being so totally ignorant about something that I experience every day.
For book 0, to simulate a strut suspension, you will need to make up something that looks like a slide-rule, as the strut length changes.
You probably won't do much better than buying Tune To Win from Carroll Smith's family or buying Think Fast from Mr. Roberts.
