ok I though I knew enough about suspension untill yesterday I started reading some stuff on a local auto x forum... well I have a lot to learn!!


does anyone know what the motion ratio is for spring vs wheel movement for the 2nd gen for front and rear? as in if the spring compresses 1", how much does the wheel move?

I'm trying to find out what my wheel weights would be with different springs rates. as I want to compare wheel weights to corner weighting measurements (not that i've corner weighted yet but I can probably guess close enough for now...)

if you don't understand or don't know, please don't bother posting.

 

opps, that was wheel rates, not weights

I think this is over everyone's heads here

 

By definition McPhearson Struts are 1:1. So the front is 1:1. I've been lazy and using .8 for the back. But I haven't measured it.

Rob

 

Hmm...very interesting question. I'm no expert here, but it seems to me there is no magic number for our cars that you are looking for. It seems to me the answer is going to depend on your suspension setup. For instance, changing your camber is going to change this ratio slightly. If the strut shaft were to extend straight down from the strut tower to where it connects on the hub assembly, without ANY angle than this ratio should be 1:1. But add a little bit of negative camber into the mix and that ratio will change. Fred Puhn's "How to Make Your Car Handle" probably has this information in it. I haven't read his book in awhile, but it completely changed my way of thinking about suspension. It is an incredible(but old)read. Try http://www.sccaforums.com/ to see if they can help.

 

It won't be quite 1:1 because the center of the hub is outside the center of the strut. On the rear you have the same situation. The wheel is moving slightly more than the spring. But you knew all that already. I'm still contemplating SPEEDRACER's comments, seems to make sense I just can't visualize right now.

Chris

 

maybe you should measure it? this is also a good time to inspect the suspension, and turn the mounting blocks for more camber stuff like that. when we took my car apart we found that both front swaybar links were completely bad, and all the ball joints are toast too.

mike
88t2 getting manual rack

 

thanks, I talked to someone else and they said the ratio changes during the stroke. as it depends on ride height as well. which would make sense on a non double wishbone.

the guy who was talking at the other forum had an integra, which was 1.3 in the front, and 1.5 in the rear. so for example. a 300lbs spring on the rear of his car, would only be as stiff as a 200lbs one on a car with a 1:1 ratio. as both cars would require 200lbs of force to move the wheel one inch.

so you say 1:1 in front, and 0.8:0 in rear? now I understand much better why people use such softer springs in the rear then in front, when I would think you would want them closer to the same.

so 400lbs front, and 275 rear springs, which is common. would give you wheel rates of 400/343. which is much more balenced.

learning is fun

 

Ahh.. that does make sense.


the guy who was talking at the other forum had an integra, which was 1.3 in the front, and 1.5 in the rear. so for example. a 300lbs spring on the rear of his car, would only be as stiff as a 200lbs one on a car with a 1:1 ratio. as both cars would require 200lbs of force to move the wheel one inch.

Do Integras have a double wishnbone suspension?

so you say 1:1 in front, and 0.8:0 in rear? now I understand much better why people use such softer springs in the rear then in front, when I would think you would want them closer to the same.

so 400lbs front, and 275 rear springs, which is common. would give you wheel rates of 400/343. which is much more balenced.

learning is fun

Yeah it is...thanks for bringing up this post. Learning about suspension and making our cars handle is much more important to me than how fast I can go in 1/4 mile is, or how much HP I have.