Ok, when I go for the recommended street alignment specs commonly posted, I am only able to hit about 3-3.4* of caster. I only know of two ways to get more:
1. Adjustable Upper and Lower A-Arms (relatively Expensive)
2. Elongate the mounting holes where the A-arms attach to the K-member (Ghetto)

Is there a happy medium here or something I am missing?

I have full suspension (UMI bits), stock springs, Bilstein HDs. I am satisfied with the steering feel, but not happy. I felt the difference going from stock specs to what I have and liked it but want to get to the ideal spec posted here by VIP1.

To give you an idea of where it's going, I will be getting A-arms and Konis (and the Watts link) down the road, but this caster issue would improve the car further now. Any help appreciated!

 

Man...no one?

 

I'm using the stock a-arms, and have lowered the car with an Eibach Pro-Kit. When I put the springs in, I took out the a-arms and lengthened the slots that the "camber" bolts go through, in anticipation of needing the extra room to adjust. However, I'm able to get a touch over 6 degrees of caster without any modifications.

Are you sure that nothing is bent in the a-arms; the a-arm bushings are OK; and the bushings aren't being prevented from sliding because somewhere in the past, the bolts were over tightened, deforming that portion of the frame, and not allowing the a-arm to slide in and out??

 

Hello
I noticed that you are having problems with your cast and camber. I would not suggest ob longing the holes out. That is not the right way or a safe way to do it. I would suggest looking into a set of adjustable upper and lower front A arms. Your not only going to be lightning up the front end its going to give you more adjustment when you have the car aligned. Below is a link to show you what all UMI Performance has to offer!

http://www.umiperformance.com/catalo...3lujpsj3a83sj3

If you have any other questions feel free to ask and I will be more than glad to help!
Thanks
Brad

 

I too have opened up the camber and caster slots. No issues after 4 years of HARD road racing. Its a common practice.

A couple things to know, though ...

The more negative camber you dial in, the more positve caster is limited. This is because of the triangulation of the A-Arm. Whatever you do to one corner, it will affect or change the other.

Next, if you get a good look at the upper slot of the caster mounting point, inside the engine bay, you will notice that the inner fender "bulges" right at the slot. So if you do open up the slot, the head of the caster adjustment bolt will hit the inner fender before running out of slot. The fix is to grind off about 1/3 of the bolt head at a 30* angle and then slide the angled portion underneath the "buldged" fender.

Using a slotted K-Member and the angled bolt head trick, I run -2* camber and +5.4* caster.

Having said all that ...

I agree with Mr. Foot ... If you can only get +3* caster with a normal camber setting, then something else is wrong.

With -0.8* or -1* camber, you should be able to to get over +5* easily.

And having said that ...

What makes you think you need more caster?

 

Leadfoot, good points. No, I am not sure nothing is bent, but it's not obvious. The prior/first owner took a hit on the rear, no front end damage. I have never had an accident in the car, though there are the occasional potholes but they don't SEEM to affect anything. Nothing is visible upon inspection of the front suspension to indicate something bent, however, it hasn't been measured, squared, or technically squared, outside of a standard alignment.

Mitch, I believe I need more caster to make steering response a bit sharper. I'd like there to be less "lag" between starting to turn the wheel and the car actually moving. This occurs both from center to turning and also transitioning one direction to the other. I don't care to have more than a degree of negative camber or a c-hair, if any, toe out. I want an assertive street alignment that won't chew up the front tires. I believe, maybe mistakenly, that additional caster will sharpen up steering feel and turn in.

Here's what I have done to fix or improve steering and suspension over the years (in no particular order):
1. Replaced the rack twice
2. Had a "custom" alignment (several)
3. Bilstein HDs
4. Strano sway bars
5. UMI PHB, LCAs, TA, SFCs, STB
6. Better tires

I suppose this rack could be getting sloppy and I want Konis before too long. Don't get me wrong, for 170k on the clock, the car drives very well. There is nothing "wrong" per se, I just want it a little sharper steering without harsher ride quality.

That's why I want more caster. I just want sharper response and more precise turn in and transitions. I think the proper alignment would be about all I can do without dropping a grand on Konis and re-alignment - which IS on the agenda. Am I off base on what increased caster will accomplish towards my goal?

 

More caster makes the steering heavier and won't help the response. In fact if you think about a Sportbike vs. a Chopper--which is more nimble? The Sportbike, which has much less caster.

What you want is faster transient response, and that comes from two things. Making the car a lot stiffer, or making the rebound damping stiffer. One just makes the car roll less, the other roll more slowly and therefore change direction faster.

What you want is the very reason that all us autocrossers know the things we know about shocks. We want transient response.... and I, for example, don't want to run ballistically stiff springs to get it and live with the compromises that come from those springs.

Hate to say it, I think it's shock time....

 

Yeah I think you are off base a tick. Positive caster slows the steering down, not increases it. Open Road Racers dial in HUGE amounts of caster to that they don't over-correct at 200+ mph.

And your HDs are fine for street duty.

That raised a flag ...

All this is on street tires or R-Compounds? Street tires have a soft sidewall to help soften the ride. So the tire rolls over a lot more.

You might try a "c-hair" more toe out. You might also might try moving front air pressures a lb or two and see what that does.

Finally, the heavier the car (especially on the nose), the less responsive it will be.

 

HD's are fine for street duty, provided he doens't want quicker transitions, which he does--at least that's how I read it. HD's aren't crisp enough for me, even on the street and there are numerous folks on this site that have had both and prefer the more crisp damping.

To each his own, but saying the HD's are "fine" is one of those general blanket statements that just cannot simply be true for everyone.

 

Just to confirm something (because it seems I'm having one of those "brain fart" moments, and can't justify the correct "theory" to myself) ...

... Toe-OUT will help with quicker steering response, correct?

... but will toe-out lead to under-steer in a corner???

As far as I know, toe-out is usually desired for any type of "sporty" or "competitive" driving, as it provides quicker turn-in, and helps REDUCE under-steer, while toe-IN will help with centered steering, high-speed stability, and reduces quick steering response.

I don't know why my brain is arguing with itself about that all of a sudden?!?!

 

As far as shock settings and steering response go, I know that I feel a HUGE difference by dialling my Koni's rebound up or down. The more firm I go, the better (quicker) the car reacts. Dial it down, and that's just it, it takes away the quick, crisp feeling (but also makes it a little more "plushy" to drive every day ).

 

Toe out gives sharper turn in, toe in gives more tracking. Too much toe-in can cause the car to not want to react on the way in, and then can cause the front to wash. Too much toe out will make the car hyperactive on turn in, wander around a bit, but then not really bit mid corner.

The thing with toe is this, you can play with it, but too much or too little leaves you with the same result, the two front tires fighting each other being the are pointed too much a different direction.

I work around zero toe +/- about 1/8" from there depending on what I want the car feel like and what it does. I normally run zero to a touch toe out, but there are cars Ive setup, like Honda S2000's that I ran a good bit of toe in on because they were so darty because of their springs, rear suspension and steering racks (the AP1's, the AP2's are much better).

In the end, you can't do anything too crazy on toe without causing a new issue. It's a very fine tuning thing unless it's all messed up then it can cause serious issues. Toe setting and damping are only very, very distantly related because both can effect response.

 

Awesome, thanks for the time, guys!

I'm glad (for once) to be wrong about caster. I understand toe and like to keep it zero-ish, since I put so many miles a year on the car.

Tires - I went from Kumhos to Firestone Wide Ovals on the front a long time ago and have stuck with them. They wear long and pretty evenly and the wet and dry traction is stout. My 275 Firestones, when on the rear, gripped better than the 315 Vredesteins. I get well over 40k out of a set of the Wide ovals and have had a couple so it's not a random sample. I have played with the pressure and usually run 31-33 cold, depending on, um...the wind. It makes a difference in comfort moreso than response from what I can tell.

Shocks - I think both you guys are right. The HDs are fine and I have no complaints, but I suspect I am finding myself wanting more than fine. The car rides better and is more taut than stock and most other cars I have ridden in (couple dozen). I only have one brief ride in a Koni car and that may well be my ticket for my stock springs and what I want to do with the car.

I wish I had nutted up for Konis the first time but since I have the HDs, I am wanting to make sure I have maximized what I have before Koni-izing.
As far as alignment, it sounds like I may squeeze a bit more out of what I have and would benefit from adjustable a-arms. However, it seems like Konis plus a slightly revised alignment may well be the permanent solution, with or without new a-arms.

 

Konis are definitely an awesome shock. No arguement there.

But to get your money's worth from them, they need constant attention. Conditions change constantly. So adjusting them is a necessity.

And for those who will come back and say they have adjusted them once and have no issues, why did you pay extra for adjustability if you are going to set them and leave them alone?

 

So you can adjust them when necessary, ie: before the track, or after the track . Or for a tighter track, more sweeping track .

For normal driving around, I set mine and leave them. But I've put them up and down numerous times in between .

However, even if you bought them and set them ONCE, at least you had the ability to fine-tune them as YOU like .

 

Damn Mitch.... why do you have coil-overs? You shouldn't because you don't play with your spring rates now that you found what you prefer. I don't know why you insist on being so short-sighted. Fine, you don't think adjustable shocks are worth a damn, and I guess subscribe to the theory that only one thing can be "right", all the while thinking that *I'm* the close minded one.....

They do NOT need constant attention that's simply in your head and there are PLENTY of folks folks here know I'm speaking the truth (because they have them). But I'm glad to see you have been able to admit Koni's are awesome shocks because before you thought Bilstien's were all anyone needed because you like them better. But then I wonder if that's because you assume you need to screw with Koni's all the time when you don't.

To those reading, all you need to do is find the guys that have had both and ask them. I can only think of two instances where someone felt Bilstien's were as good or better performing. One is ride oriented, the other is Mitch.

 

Exactly. You set them and leave them, but didn't you play around to find what settings you liked best? Can't do that with shocks that aren't adjustable. Some folks aren't comfortable with changing them. It's not scary, and if you do something you don't love, change it back (or part way back). There are no monsters under the bed, and anyone, racer or not, who is seeking to make a car work the best it can can benefit from damping adjustment. After all, the car doens't know it's being "raced", shocks are simply damping the rate and speed of movement which is as applicable on a street car as it is a race car. Maybe more so given softer springs and the greater movement a street car might have.

 

Because as far as I understand from doing my homework in the past, there exists a setting on my konis that dampens most aftermarket springs well. My conclusion was that there was nothing out there that provided that. I'll pay for adjustable shocks if there's no non-adjustables that will be good enough for lowering springs. I got these when I was on stock springs for a few years and before strano springs came out.

I may still play with them sometime though.. just been too lazy. I should play with them though since now days I do mostly short oval track spectator drags. I'm learning as time goes on that the optimal setup will probably somewhat steer me away from an optimal autox setup. Though the autox setup was a good start.

 

LOL ...

I've never said Konis were junk. I have said they were OVERKILL for a daily driver, though.

I have said HDs were a fantastic shock, head and shoulders above stock and plenty of shock for street duty.

And I still stand by that.

The truth?

You make more profit from Koni sales, so sure, you are gonna fleece many of your customers into a set of Konis. And like a used car salesman, you talk them into it, they get installed and compared to the 100K mile Decarbons, Sam has hung the moon! Truth? Sounds more like taking advantage of those who are not very educated in this particular subject.

I don't buy into your hype, Sam. Never have.

But your "Look at me" threads are quite entertaining ...
I have numerous e-mail and PM from folks tired of your self-serving BS and asking real tech questions. Why PM or e-mail? Because they are tired of getting their threads spammed with vendors wanting to make a sale.

 

What if it's a guy who might go with lowering springs in the future on his daily? I think that applies to a large crowd and would think Konis is your #1 choice for that.