understeer how do I minimize it?

[joshh]

And besides, my point is not that "Because Spec E30 uses H&R Races they are the best you can get," it's simply that they obviously don't suck.

You're not wrong but what is he doing with the car....

[Fidhle007]

And besides, my point is not that "Because Spec E30 uses H&R Races they are the best you can get," it's simply that they obviously don't suck.

[Fidhle007]

When was the last time you have your car corner balanced?

[nando]

You realize that about 17% of r3v member will actually take the time to set up their coilovered cars, right? Coilovers that have not been set up properly (Yes, with scales and all that other shit) are completely pointless and a waste of money. For the everyday driver, and most other folks too, it's best to go with a setup where most of the hard work has been done for you. Spec E30 wouldn't use H&R Race springs if they sucked...

they use them in the interest of cost, not because they are the best thing you can get.

[atomic]

http://www.rogerkrausracing.com/Tech...verunder.shtml

[Fidhle007]

Terrible advice! lol

If you're going to buy another spring/shock setup, just man up and go with a ser of coilovers.

Only if the OP has scales. Otherwise you're wrong. Coilovers are just an expensive way to fuck up your handling if you don't have the capability to set them up right.

[Fidhle007]

You realize that about 17% of r3v member will actually take the time to set up their coilovered cars, right? Coilovers that have not been set up properly (Yes, with scales and all that other shit) are completely pointless and a waste of money. For the everyday driver, and most other folks too, it's best to go with a setup where most of the hard work has been done for you. Spec E30 wouldn't use H&R Race springs if they sucked...

[DSP74]

Terrible advice! lol

If you're going to buy another spring/shock setup, just man up and go with a ser of coilovers.

Agree. BTW the Cosmo kit comes with rates I've seen similar to HnR race.... And I read today on another forum that the springs are 2.5" ID springs not some stupid 3.5" or whatever it was spring people were saying they came with......Probably OD 3.5"

Then you can change to any rate you want in the future too.....All for CHEAP.

[z31maniac]

The cup kit is pretty low and soft, I'd go with an H&R Race (or IE III)/Blistein Sport combo and see where your at.

Terrible advice! lol

If you're going to buy another spring/shock setup, just man up and go with a ser of coilovers.

[Fidhle007]

Wow!! Thanks to all for the comments. I will be a little more specific on what I have in my setup.. I mentioned that I have a H&R Cup kit, so that suspension. The car is an 89 325is. It has stock sways and I have changed the tires and wheels. I am currently running 15" team dynamics race 1.2s. They are wrapped in toyo R888 tires ( 195/50r15). I primarily run the car on road coarses, I haven't run an autox yet and don't plan on doing that to much. I would like to change the suspension out to a coilover setup, and from the chatter here maybe just add adjustable end links to my stock sways. Along with playing with the tire pressure. Thanks again for all of the input. Oh ya.. brake more before turning, accelerate out of the turn...

The cup kit is pretty low and soft, I'd go with an H&R Race (or IE III)/Blistein Sport combo and see where your at.

[Emre]

Converntional wisdom on a BMW is to run stiffer springs in the rear than the front (usually 150-200 pounds different).

You can't simply compare the front and rear spring rates directly. The rear rates are effectively much lower due to their location on the trailing arm. Once you factor in the difference, you end up with a front that's effectively much stiffer than the rear.

Stiffer springs in the rear are only due to the motion ratio in the rear.

Exactly.

I run a stock front sway and no rear bar on my E30 track car. Big sway bars are the American way to tune the suspension, springs and shocks with fine tuning from the sways is the European way to tune the suspension- not that one way is better than the other.

Whether the stiffness comes from springs are sways is a different matter to be debated in a different thread. The point is that if you want to eliminate understeer, you need all the roll stiffness you can get at the front of the car. Whether that roll stiffness comes from springs or sways is another issue.

[hendrik]

Wow!! Thanks to all for the comments. I will be a little more specific on what I have in my setup.. I mentioned that I have a H&R Cup kit, so that suspension. The car is an 89 325is. It has stock sways and I have changed the tires and wheels. I am currently running 15" team dynamics race 1.2s. They are wrapped in toyo R888 tires ( 195/50r15). I primarily run the car on road coarses, I haven't run an autox yet and don't plan on doing that to much. I would like to change the suspension out to a coilover setup, and from the chatter here maybe just add adjustable end links to my stock sways. Along with playing with the tire pressure. Thanks again for all of the input. Oh ya.. brake more before turning, accelerate out of the turn...

[DSP74]

Yep, but the front is also much heavier than the rear. The front spring rate as a function of how much weight the spring is carrying is still probably somewhat less than the rear rate.

Factor in that the front is a little heavier not alot, and the swaybar rate then the front is still stiffer. If the car weren't stiffer in front it would be literally undriveable.

[DSP74]

I can see situations where the body roll transfers enough weight to the front outside wheel that it overcomes the mechanical grip that the tire produces therefore causing sliding and understeer. In that case, either stiffer springs or a stiffer roll bar should help decrease understeer by balancing the weight load a bit better.

Body roll doesn't transfer weight.


All cars regardless of independant suspension or not lose camber on body roll.....A car that didn't would have roll center movements all over the place and braking would suffer. Probably alot.

[Hallen]

Stiffer springs in the rear are only due to the motion ratio in the rear.

When comparing wheel rates INCLUDING THE SWAYBAR (which is difficult to accurately calculate) the front is much stiffer....even if you stick with a stock front bar and no rear.

Yep, but the front is also much heavier than the rear. The front spring rate as a function of how much weight the spring is carrying is still probably somewhat less than the rear rate.