Front/rear sway bar questions

Ralphatron

yeah, I think what I'm going to do first is move the end link to the outer hole (softest setting) on the rear sway. You're saying just unlink one side and basically leave the endlink hanging there to test this out? any potential issues I can run into while driving it this way for a bit?

Yeah, the adventure I've been on the past few months trying to get this right has taught me about all the factors that come into play with suspension.

the second coilover kit I put on had custom swift springs at 12k in the front and 7k in the rear (true rear, not divorced spring). This was BRUTAL to drive and I immediately threw on 10k/5k swifts and noticed a huge difference. But I assumed the custom valved dampers for the 12k/7k original springs on this kit were causing it to still be too stiff for daily street driving.

That's why I went with a completely new divorced spring kit, using default spring rates of 10k front and 8k rear. As I'm sure you know, the spring rate is basically double for divorced spring vs true rear coilover spring due to the wheel rate.

This was also noticeably better, but I'm still feeling what I think you described as "darting" (car slightly being thrown left or right I think?) when hitting bumps with one side of the car only.

The other thing too is that I have yet to get my alignment done, because I wanted to finalize my configuration before spending the 100 bucks and avoid having to do it again if I wanted to change something. I know this will affect handling, but I didn't think it would be enough to cause my issue, right?

As for ride height, I'm not slammed, and I'm not at stock height. I'd say right now I'm noticing this at maybe 1.5 inches lower than stock, so nothing extreme but was planning to fine tune the height adjustment to maybe a half inch lower than it is now, just waiting for springs to settle a bit first.

I'm not really sure what down travel is. I'm on the default dampers that come with the BR series coilovers from BC and I have them set to the softest of the 30 available settings.

I appreciate the responses, guys, thank you!

Rusty

You screwed up by not getting an alignment done. Everytime you change coilovers and springs. It changes your ride height.

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Ralphatron

lol, I said I haven't done the alignment yet since I'm trying to finalize my configuration and final ride height. I'm definitely planning to get it done as soon as I decide what I'm keeping on the car. Why would I get it aligned if I know I'm going to change the suspension configuration and then have to re-align it again at $100 bucks a pop.

geokots

Because not getting the alignment won't give you a true indication of the ride/fitment.

Rusty

Everytime you change spring rates. You have to get it align.

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Rusty

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Ralphatron

lol I'm fully aware of why an alignment is needed and what it can do to the car when it's not aligned. Not just by being told or reading it, I've actually experienced it many times back in the day on my older cars.

Right now I'm specifically talking about the way the car handles over imperfect roads. The car actually feels great going straight on smooth roads, and even on smooth turns. but I'm specifically talking about hitting bumps on one side of the car only. If you guys are convinced it's my alignment causing what I'm feeling and can prove it to me somehow I'd be happy to send you an amazon gift card lol.

geokots

LOL so I get a gift card if I do the work for you. Doesn't sound like much of a deal. How about you do the work properly and send me a gift card when I'm right.

Ralphatron

The point was that I can bet an amazon gift card that an alignment is not the problem here. Please go back and read my original post so you can have a better idea of what I'm dealing with because it doesn't seem like you do.

Or you can explain to me in technical detail how camber, castor, or toe adjustment would cause a bump on one side of the car to feel any different instead of assuming an alignment will fix all my issues.

The car does not pull to the left or the right at all. There is no visibile uneven tire wear anywhere. And when I go over bumps or divots in the road that cause BOTH sides to move, I don't have this problem. So again, please explain to me how you're so certain my alignment is the issue?

victorofhavoc

you ever see a car drive straight down the road but it's sitting sideways? That's the result of frame damage or an alignment where two wheels on an axle pull one way while the others pull the other way. Improper alignment may result in the car going straight fine, but being lazy turning one way, and fast another way. If the bump comes at you anything other than head on, chances are the wheels will start to pull in opposing directions at different times and with varying forces. - That's why alignment *could* affect what you're feeling.

The other thing to consider is type of coil. My car sitting on Bilstein monotube coils with about 400lb springs rides like a stiff brick compared to my racecar on kwv3 with 14k front and 10k rear springs on slicks. BC are not exactly known for having the most comfy coil out there, and each person's expectations are usually different. If your ride height is close to bottoming out the coil or only one of them is at a lower than expected height, you can be left with odd bump characteristics that ruin the ride entirely. Combine being too low with a super stiff monotube damper and it likely won't be comfortable, even on the smoothest of racetracks.

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wanker

How about purchasing a lifetime alignment deal? They are usually only a couple of hundred bucks.

Also that "darting" sensation you feel likely means that your car is "slammed." The springs are fully compressing.

I'd raise your ride height at least 1/2" and get an alignment.

Rusty

Everytime you change springs, the valving inside the coilover/shock should be change to match the new spring.

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Jhill

He got a complete new kit BC BR 10/8 so that’s not the issue anymore. With his BC BR his ride height isn’t done by preload so that eliminates the slammed no travel issue. Definitely need to get your alignment checked because if your front toe is set - then it will absolutely be twitchy and darty (that’s why it’s done on auto cross cars). As for the bars I’m going off memory here and again totally different car with different suspension design so not even close to apples to apples but I do remember when I had the stiffer front bar before the softer one I put on later trying to eliminate under steer but I also found I had less kickback in the steering wheel on uneven rougher roads. Not sure if that’s what your feeling but ruling out the sway bars is easy enough by just disconnecting it. I guess I’d also pay attention to if it’s darting directly after the front wheel hits which would lead me to think your describing what I felt vs directly after the rear hits like it’s causing the car to step out.

It does seem more and more people are running no rear bar which is something I wanted to try at a safer track like button willow and learn to throttle steer better but then 2020 became a **** show so never got any track time in.

Brendan

With springs that soft you should still have a lot of down travel. Without knowing anything else I would look at alignment.

And yes, by darting I mean rapid lateral movement independent of steering angle or input.

victorofhavoc

Tramlining, rapid darting, or following every bump in the road can be a result of a lot of camber.

__________________
Had a 2010 WRX- boy was it quick in a straight line, got a 2014 Z- man is she grippy in the corners-- then left the Z and later got a GTI, now back in an 09 racecar Z!