Smogrunner

iTrader: (5)

Great thread. I really appreciate the openness of Joe and Paul. Others are so secretive that it is hard to decipher whether it is true protection of IP, marketing hype, or just clever concealment of fairly low quality hardware. I've been accused of drinking Paul and Joe's Koolaid (i.e. of being brainwashed) when making the suspension choice of going with the Vishnu Spec Ohlins. So be it.

Joe, have you ever cracked open a set of Buddy Clubs or JICs that many Evo owners run? What are the primary differences on the inside between them and the Ohlin's R & T?

chronohunter

iTrader: (1)

Smoggy AFAIK they use a triple progressive stack of marshmallows on the compression side and vertically skewered gummi bears on the rebound side

It's actually amazing how different shocks are on the inside, Joe can tell you all the differences in detail (for all that can be taken apart, many are not). The units that are similar if not identical are the Ohlins/Penske/Proflex/JRZ/ProTrac/Moton/(etc.).

Now go drink your Kool Aid!

Smogrunner

iTrader: (5)

gulp, gulp, gulp.... wait-a-sec, this ain't Koolaid, its Sam Adams

Djazair

iTrader: (1)

I haven't tested JIC or Buddy Club. Most shocks are very similar inside: piston, shim stacks, floating piston or reservoir, three ways have a 2nd shim stack or spring loaded blow-off valve. The *BIG* difference is in piston and seal design. The top companies have the R&D man power and money to try tons of combinations and new experiments. Once they come up with something good, they patent it. I know for fact that every Penske and Ohlins piston is patented. The smaller guys then can't copy it. Having more variables to play with gives me more options. Penske for instance, you can have the same shim stack, with a different piston, get relatively the same overall damping force, but drastically different curves. If you need to tune for certain situations you now have those options. Watch ChampCar, the front runners and back runners can perform close together in nice smooth long turns. Throw in some bumps (in a braking zone) or wild transitions with curbs, then watch which cars get tossed around. I've been lucky enough to find out what some of the top guys use, it's really trick stuff and super expensive ($7k+ per shock), but the car will perform over anything.

It is hard to decipher between marketing hype and true IP protection. I've tested many shocks out there and Paul has driven them. But we're both consumers too and who wants to spend good money on an unknown. In development and endorsement of a product, we feel that support thru consumer education is the best way. You learn what we do and more importantly why. This way you can make the best decision for yourself. It makes for good customers too, because they know exactly what they're buying, no surprises on either end.

trinydex

iTrader: (12)

bump for renewed links?

trinydex

iTrader: (12)

i never noticed this question before. are you referring to pumping effect?

or are you pointing out that overstiffening the springs causes skipping?

Noob4life

I think he is referring to a car's tendency to skip or hop through a corner, never quite taking a set. I could be wrong.

IMO part of the upper limit will be defined by available grip and downforce. A car with a more grip and downforce can get away with running much higher rates than compared to a car with minimal aerodynamic elements and street tires.

dsycks

iTrader: (10)

Once again it may be a rather complex set of issues involved. For one I think the chassis of the race car is FAR stiffer which is a bit of a double edged sword.

On one hand you have much more precise control of the actual working bits of the suspension but on the other you some flex in the slop of an underdamped chassis which I have seen some say is not so bad but I think it's unpredictable and counterproductive.

It may be that the lack of deflection and predictable and focused fashion in which a race car exerts force on it's suspension allows for better use of higher rates. May also have something to do with the fact that many race cars have modifications to the geometry by moving pick up points or changing lengths of arms. This can also change ratios which have a direct effect on how much of the spring rate the suspension actually sees but that may be less an issue in this regard.

I also think its a good point to address downforce and traction. It's really not all that hard to make a few hundred pounds of downforce with simple aids and that is enough to make a pretty noticeable difference in some cars.

Of course the tires that you put on a race car are often nothing like what you may have on something set up to a lesser degree and as we all know, tires makes the single biggest difference in any set up.

It would be interesting to take a car or few similar cars on the same day and work out some of these issues.

GTLocke13

iTrader: (1)

I agree, great thread. But while Joe's openness with his methods is commendable, he could as well have said, "I place the shocks in a silver bowl full of used transmission fluid and set them on the altar under the light of the first full moon after the Chinese new year," and most people would take the same amount of information away from it. Even for the few of us who know what he's talking about, that is a WHOLE lot of work to construct those simulations. All I've taken away from it is that my mental image of how a suspension works is way too simple.

BTW, in taking apart shocks, have you disassembled any Koni yellows, and if so, was their engineering up to snuff with the big guys you mentioned?

toovira

iTrader: (2)

This is pretty good:

http://farnorthracing.com/autocross_secrets.html

Read the "Suspension" section.

Oh yeah, there's MUCH more to it than spring rate/damper. You wouldn't believe how much you don't know until you start reading magazines like "Racecar Engineering".

Obviously, suspension gemotery is extremely important. A lot of people lower the car because "it looks good" or "lower the CG"....sometime, you really shoot yourself in the foot doing that. I mean the ideal suspension system is the wheel travel up and down perfectly, but you notice how most suspension joints are pivot points? So everything goes up/down in radius....which means the suspension can "push" the wheel in/out or forward/backward.....which changes the contact patch and even handling characteristic of thecar.

chmodlf

iTrader: (19)

I am also interested in the Koni quality ;-)

dsycks

iTrader: (10)

Konis are very simple. It's "old" technology which is good and bad.

You get a simple reliable system but also one that you can upgrade easily by putting it together with thicker synth fluid in them and get a nice stiff happy damper that will resist fade better than many of the non competition dedicated coilovers that are currently on the market.

The sad news is that the majority of stuff we see on the market is crap.

Maybe some folks need to take the jump into cutting up some base dampers and putting koni 8611 inserts in them. THAT would be an interesting write up and experiment.

chmodlf

iTrader: (19)

From your post I am not clear on what is bad about the Koni's?

killthelights14

iTrader: (2)

http://www.fatcatmotorsports.com/feedback.htm

go to chassis setup
suspension spreadsheet and go through the excel tabs on the bottom and play with setting.

that really shows you how the setup works in a car. This spreadsheet is setup for a miata but the values can be changed...but mainly used to references.

enjoy!

GTWORX.com

iTrader: (35)

Awesome thread.


- Andrew