Anyone see issues with this besides putting a angle on the FLCA bushings? Yes I know you can buy the bolt/washers at any local store. I'm just asking about the design of the kit.
http://www.whiteline.com.au/product_..._number=KCA301

 

The design? It's a bolt and a bunch of washers...

You can increase caster by swapping UCAs left-to-right also, and that's free.

On a sidenote, I can't believe they're charging $47 for that!

 

wow, thats terrible

 

"The design? It's a bolt and a bunch of washers..."
I should have been more clear. I was looking for guidence from some of the more math inclinded members to make sure I wouldn't hurt other geometry (bump steer, camber gain ect) by adding caster in this way. Swapping upper arms adds caster but you cant adj to even out caster from side to side.

 

Ah, gotcha. I'll leave that to the more math-inclined members

I think I can safely say that will not affect the camber curve though, and that increased caster in general will increase bumpsteer.

 

I heard the bolts on those kits sometimes break.
Some other whats his face guy complained about horrible bump steer when swapping the UCA's.
Pure anecdotal evidence and zero theory - how about that?

 

for what it's worth swapping the UCAs comes out pretty even in most cases. Mine wound up at 3.2 on both sides and I've seen a number of others that landed right there as well.

 

Should have left it to the math wizards! Changing caster will defiantly change the camber curve, generally most people increase caster to increase the rate of camber gain with bump.

 

Whoops! Well, there you go! on me

 

If you really want to put something like that on your car... Gawd knows i wouldnt. save the 47.00 and hit up a local hardware store and buy it all for what 5 bux?

Who ever offers that should be shot, or congratulated for liberating a fool, and their money!

 

Stinky:

I believe your original assertion is correct.

The Whiteline kit increases caster by moving the LBJ forwards. The caster is (mostly) the angle between the UBJ and LBJ as viewed from the side of the car. The kit does not move the LBJ inwards or outwards from the center of the car. The location of the UBJ and LBJ relative to the center of the car (as viewed from the front) and the arc that they swing out determines the camber curve. The kit does not change the shape of the LBJ curve, as viewed from the front of the car. Thus it does not affect the camber curve. Maybe it does a tiny bit, but the effects are secondary.

Further, I don't think "most people increase caster to increase the rate of camber gain with bump". If you wanted to do that, you'd muck with the UCA mounting point. People mess with caster to increase the rate of camber gain with steering.

 

I still don't believe so, what kind of suspension do you ride on that is not put in a state of compression while turning? And then why would you want to gain camber while turning?

 

I was one of the guys that measured the bump steer change with swapped UCA's on EG/DC chassis' cars. It does a number on bump steer.

DB2-R81, you're mixing things together. Your camber curve is the measure of camber gain in bump. It does not include suspension movement caused by chassis roll. Caster affects caster, and a 2nd order affect is that as you turn the wheel, you get dynamic camber.

To the OP, why do you think you need more caster? I run stock caster on my car, (hell, stock control arms and pivots too, honda did a remarkable job with the geometry right from the factory) and have achieved 1.4g's sustained lateral acceleration.

 

...and too much caster will dilute steering feel and increasing steering effort...among a few other elements. I point those two out because a decrease in feel along with an increase in effort can make a car very difficult to drive fast. - through turns

 

No I am not mixing things up, you are looking at elements in a static situation, in isolation for analysis, I am referring to what actually what happens in a dynamic situation when the steering wheel is turned.

 

Solo-x, I'm not sure I need more caster but my caster is not the same side to side. I figured to only way to know if more caster would help me is testing at the track. It's quite cheap to change if you get parts from the hardware store. I have sustained 1.3g's but that last 0.1g that you speak of couldn't hurt right?

 

...steering wheel turns, dynamic camber changes based upon caster angle, camber gain (SLA) and static camber.

 

I actually have that caster kit sitting on a shelf, unopened. Don't bother wasting money on it.

I have no issues with Whiteline as a company, as they seem to overall make good products. This one very much seems intended for a street car that won't see the harsh conditions of track use.

This kit spaces the LCA halves apart, to move the LBJ forward, to increase caster. Due to the spacing, the bolts holding the 2 LCA halves now run through the holes in the LCA at an angle. To allow this angle, the kit supplies longer bolts that are skinnier than stock, which is issue #1 for me. Issue #2 is that the washers/spacers are flat, when the LCA halves are now at an angle to each other. Combine these 2 issues, and I wouldn't trust them to hold up while banging curbs on track.

As it is, I'll give away my kit to a brave test subject willing to come pick it up, on the conditions that it will be used and any failure reported on here for others to know about, but you won't find it in use on my car.

I'll also add that my personal experience agrees with solo-x's numbers. I ran swapped caster adjusting UCAs for increased caster. The swap is good for around +1.5* of caster, SPC UCAs offer +- 1.5* of caster adjustment, and my DC2 had +1* stock, providing a total of +4* of caster. Turn in was fantastic, steering effort was much stiffer (an improvement for my preferences), the car tramlined significantly less, and the self centering of the steering was significantly improved. I also went back to stock caster (and stock UCAs) to get rid of the horrible bumpsteer issues I had.

With the caster, the car felt fantastic on course. Without the caster, the car feels worse, is easier to drive, goes faster, and doesn't try to rip the wheel from my hands if I find a pothole...

 

By "turning", do you mean that the steering wheel is turned, or that the car is busy cornering?

Most suspension compress on one side when turning / cornering and extend on the other.
Getting additional camber gain while steering is nice because steering usually implies an intent to turn / corner. Thus you can have slightly less camber for straight line driving and braking, and more (negative) camber while turning / cornering.

 

In all honesty, you are mixing them. Caster doesn't affect the camber curve because the camber curve does NOT include steering angle. It is a measurement of the camber change in bump and it is defined by control arm lengths, angles, and attachment points, NOT steering angle.

It's not a matter of semantics, it's a matter of using the proper terminology in the correct context so everyone participating in the conversation understands what is being discussed. It is done this way for a reason.

 

...why I wrote what I did in post 17 solo-x...I had more than a hunch that you knew the difference.

 

Look you can write all you want about your perceived definition of a camber curve however there is nothing in the definition of the words camber curve that delineate a zero degree steering angle. Anyone can measure a camber curve at three, five or twenty-five degrees of steering angle. Likewise at any steering angle other than zero, caster affects camber, period.
I don’t know how much time your car spends at a zero degree steering angle, not much I would hazard to guess, mine is more likely to be found off center.....

 

Would you consider the UCA swap if their was a way to correct the bumpsteer you gained?

 

Here is scott's measurements

https://honda-tech.com/forums/road-racing-autocross-time-attack-19/dc2-bump-steer-data-2639712/

IMO not that big of a change from stock..

you get ~.04" of toe in on bump and ~.051" of toe out extra with the UCA swapped.

 

I prefer to evaluate them seperately; I prefer to look at the two AND then the sum of the two...they create different compromises. Caster doesn't affect RC or IC for example...fairly important I should think. I might prefer to use less caster - or none - and avoid the increase in steering effort and the potential loss of feel. None of this is written in stone but the two do not work the same...and caster throws weight to the wrong rear wheel in the unfortunate opposite lock condition...maybe this is good for drifting though, I've no idea.

I persononally consider caster to be a convenient conceit...but we have to live with that compromise at some level...well, mac strut aside...I guess...


slammed 93 hatch...does ~ .051" of toe out also corrspond to roll toe out? ...and therefore toe in on the inside wheel?