Hi everyone I guess I should start out with my car. 1994 Acura Integra LS with the following modifications:

Tein Type Flex Coilovers (10k/7k Spring Rates)
Skunk2 Front and Rear Camber kits
Comptech Rear Sway/Tie Bar Combo (Hardest Setting)
15" x 7" 5zigen FN01r-C Rims
205/50-15 Toyo T1R Tires
Password JDM Strut Tower Bars (3pt front, 2pt rear, 2pt trunk)
Prothane Rear Trailing Arm Bushings
Energy Suspension Front Sway Bar Bushings (Torqued to Stock Settings - A friend told me to loosen)
Prothane and Energy Suspension Motor Mounts
ETD Traction Bar with dual mounting LCA points
Earl's Brake Lines
Hawk's HP+ Brake Pads
Motol RBF 600 Brake Fluid

Since I have the ability to alter any angle I choose, whether it be Toe, Camber, or Caster, I would like to hear some of your inputs on my next alignment settings for the car. I do spirited driving for my company (3000 Miles of Pavement) and plan on joining some HPDE's in 2010. The car understeers moderately

Currently the ride height is 4.25" F and 4.50" R measuring from the jackpoints on the car. Does this seem acceptable? Should I rake it back down in the front to a 1/2" difference?

Current Alignment settings:

Front:

Camber: -2.6 Degrees
Caster: -0.1 Degrees
Toe: 0

Rear:

Camber: -2.6
Toe: 0.10 Degrees In

The traction bar can now pull out the front end to better settings, any suggestions on how much caster to run? From what I have heard, Toe out of 1/16-1/32" in the front with 1/8-1/16" toe in the rear would help with stability and turn in while not creating too much scrub off from the tires. Caster angle has been debated among three of my tuners of 1'10 Degree (stock setting), 5 Degrees (or as much as it will do, as long as it is 5 or under), or 3-4 Degrees (Front wheel drive suggested max caster settings = My top choice).

I plan on running 20k miles on a set of maximum performance tires such as either Bridgestone RE-11's or Kumho XS in a 205/50-15 since the Toyo T1R's weren't grippy enough and are just about gone (inner tire wear resulted from too many straight roads + high speeds).

Thanks for reading, please help me out if you have the experience and knowledge. This is my 7th custom suspension setup, and this time I would like to hear some of your feedback before just going by my SOTP driving.


-Ryan

 

Come on, I know there are some suspension gurus on this site.

Anyone track their car a lot?

Another thing, tire selection: 205/50-15

Yokohama Advan AD08
BFGoodrich G-Sport
Kumho Ecsta XS

 

really if you have done this 6 times previously then you should know what you like and how you want your car to handle. there are tons of people on here who will tell you a ton of different setups to run. one thing you should look at doing is getting your car corner weighted since you are getting really in depth.

 

The problem I am having is knowing what I like, but not knowing how to set the car to make it handle like I want it to.

Suspension tuning is the hardest aspect of automotive tuning, and I am barely at the tip of the iceberg.

This is what I plan on running, but I would like to hear from these "tons of people" first:

Front:

Camber: -2.5
Caster: +4 Degrees
Toe: 1/16" Out


Rear:

Camber: -2
Toe: 1/16" In

Does anyone have past experience running high caster angles?

 

well...
a. how do you like your car to handle??
b. you are not going to find alot of people on this forum who mess with caster. also you say you want higher caster?? correct..as in more positive caster??

 

Right now I want the car set up for mid to high speed cornering without any downforce adders such as wings, splitters, smooth underbody, etc.

Yes I did want positive caster because of that, but I am unsure of how much exactly (3-4 degrees being a general setting for front wheel drive cars).

Oops, I am sorry, I guess one of my edits did not work, and I am missing the info that I previously stated (or so I thought).

The car currently understeers moderately, and the shock valving seems just about perfect. When I go over a bump, I receive one jounce and the car settles. I never have two jounces, and it is never too stiff to not drop in a hole or whatnot. One problem I am having is that I do not feel planted at higher speeds and rather disconnected from the road. Under hard braking, I have a bit of shimmy through the steering wheel, and under acceleration I am dead straight.

I know for a fact that my car needs corner balanced and when I get the money, I will do so, but for now, just an alignment will do. The cage and harnesses will come before the corner balancing, as well as gutting the interior. I plan on moving this car towards a weekend warrior class and less of a daily driver with soft/moderate spring rates that are good for just about any surface (current setup).

Any insight for my needs at all would be appreciated.

Thanks again,


-Ryan

 

Toe is the most important setting of an alignment, would you say that my future settings are acceptable? Any idea for improvement?

Camber angle, second to toe, I have always run 3-3.5 degrees until this last alignment and the car just doesnt handle as well as it used to when pushed to the limit. Older setups were -3.3/-3 which I loved (4 wheel drift machine), -3/-2.8 (light understeer), -1.8/-1.5 (lack of traction during cornering), etc etc... I forgot a lot of my previous settings. Toe was always at stock settings (0 front, 0.1 Degree in rear).

 

honestly you sound like you know how your car responds to different settings.

sooo...

the caster thing. adding more caster is going to make your steering feel heavier and i dont know if that is going to benifit you as you would like.

you say the car understeer slightly which obviously is the demise of a fwd car. but do you feel you could loosen up your rear end at all?? i know your problem is faster corners which im assuming is ~50-70mph but i dont know if your problem is your car is pushing too much at higher speeds or if it feels as if it is kicking out on you.

now onto he said she said. lol. this is my opinion. toe out in front is going to help you tremendously in slow corners but as the speed picks up it might push a bit more due to weight transfer and the outside wheel facing away from the apex opposed to zero toed setup. toe in on the rear will help with your straight line stability but in turns i think that is where you are getting some of that instability. here is how i picture it...once again just picture a car in the turn. lets say a right hand turn...weight transfer goes to your left rear tire and with it toed in at this point it is now scrubbing against the contact patch. yes in theory it should help the rotation of the car but i dont think it would be as benificial as you just doing toe out in the front. also i think that your car will be very twitchy with toe out front and toe in rear as your speeds increase.
*disclaimer:these are my view and are not expressed by anyone else except myself. lol.*

i hope just this bit of info helps but like i said i think you are on the right track. i mean that mid to high speed cornering could become smoother with better tires or different offsets or wheel widths. maybe even possibly different tire pressures. lol. as you can see this has many variables..which you already know.

once again i hope this helps somewhat.

 

If anyone was wondering why my caster angle is so bad, well you can thank both Sk2 for a poorly designed UCA and the previous owner for having a small crash. Thankfully it was properly fixed at the dealership and they are at least even from side to side.

If you swap sides of the Sk2 camber kits, a positive caster gain will be found (Right on Left and Left on Right). This is also the case with the stock ITR UCAs.

Caster angle is something I'll have to experiment with more. Now a days, engineers are using more and more of the caster angle in car suspension design (even the new civics have around 8 degrees positive). It used to be around 3-4 for the FF cars and 5-7 FR, but all these old "rules" people used to go by have been crossed and from what I can tell greatly improved.

So on this car, I am thinking of maxing out the caster angle (hopefully without breaking any other components) for my custom traction bar. Thanks again Robert @ MillPro.us for rethreading my radius arms after I cut them down to proper sizing.

 

The one thing that I forgot to mention in this thread is that the positive caster angle will create more negative camber angle once the wheel becomes dynamically changing direction.

I can tell that when I was running the larger differences for camber angle (-3/-2.3) the car would oversteer much easier and was much less balanced when at the limit.

So I guess I am back to square 1 then. I need help defining toe characteristics for a mid/high speed cornering setup. Those speeds would be 50-100mph at the apex of the corner. The lower speed corners are much easier for me to handle, and these are where I am losing my adhesion prematurely. Just as a reference, with the -3.3/-3 setup, I had the car at around 1.2g with neutral handling, but bad high speed stability with wobble.

 

yes this is correct. that is why alot of newer fwd cars have more caster is due to the fact most have the mcshitson front suspension which obviously has crappy camber gain.


im running zero toe on the front and rear with -2/front and -1.5/rear camber. rear biased sprung car. no arb in the front and stock ex arb in the rear. at gingerman last weekend most corners in my car with the d16 is around 50ish on average for the tighter turns..8 and 9 are around 65ish. when the tires arent greased to **** the rotation was awesome. but then again i like that loose rear end feel and it got looser as the tires went to junk. but it was never like i felt the car was unstable..just sometimes turn in was a big push.

 

I cant believe how this suspension forum has so many threads reappearing with the same questions and everyone answering them over and over, when only you can answer mine.

I am guessing these guys pull numbers out of hats? **Ahh -2/-1 will be good!**

Anyways back on topic. So I think I will run that 4 degrees caster angle against what one of the tuners Ive talked to said.

TOE is what baffles me now.

 

Just something to keep in mind:
The DC chassis has very little bumpsteer, regardless of ride height.
However, adding caster adds significant bumpsteer.

I run +4* of caster on my 2000 GSR. During auto-x, I can just drive through the bumpsteer, but it is problematic on track and on the street at times.

 

I am thinking of getting the whiteline kit on my car to help with my radius arm (since I dont want to actually PULL out 4 degrees by just using that).

Anyone know what the kit comes with? Actual sizes of parts? Anyone have a kit for sale? Know where the best deal is for either local pickup or shipped?

 

The Whiteline caster kit?

Its 4 bolts, and a bunch of washers.

It would be a much nicer kit if the washer/spacers were tapered, instead of flat, due to the angle installing them creates between the 2 LCA halves. I've also heard of a couple of horror stories of people breaking the supplied bolts on track. They are thinner than stock, since they have to go through the 2 halves at an angle.

I have the kit sitting on a shelf. I took one look at it after receiving it, and decided to try getting caster other ways. You can find them for $40 or so online.

I don't think the kit will work for a car with traction bars installed. It spaces the 2 LCA halves, and a traction bar install generally removes the back half to install radius rods instead. Just shorten your rods to increase caster.

 

4deg is still alot. i think the eg/eh chassis oem spec is like 1.17deg so i am assuming the dc is very close to that.

also you talk about mid and high speed corners. so with toe just start off at zero front and rear and adjust accordingly. i was going to go toe out in the front with the new setup..but after my last track event im staying zero toe due to how the car handled.

 

Thanks for the info on Whiteline's kit. So you guys think that 4 degrees is too much on the DC chassis? The stock setting is 1'10 Degrees, but from what i've heard, the more the better on almost any car (5 is about the general limit for double wishbone FF).

Has anyone done toe in on the front end of our cars? Wouldnt that also develop better high speed stability?

I just spent 5 hours today working on balancing the car a bit better (no scales though) using a SOTP feel, and here are my current ride heights: Front=4 9/16" Rear=4 31/32"

This gives me the grip I need for on the throttle turn ins, and also does not cause the car to plow into a corner like it did on my previous setup.

Toe is a mystery atm, and caster is as much as I can do without pressing against the rear of the front tires (moving them forward forcefully). Camber is probably around -2.8-3.0 in the rear and front is probably still -2.6-2.7.

TunerNoob, if you dont mind, could you post up your alignment settings? How does your car handle at the limit? past the limit? Besides the bumpsteer issue, which I believe the traction bar will almost fix, how does the car feel?

 

i dont know the heights of my car but i have my car raked probably close to the difference of your settings. and i wouldnt put my cars on the scales at the track because wellllll....i was afraid to see the cross weight ratio. lol. but i loved the way the car rotated on the track. with adjustments could it have been better?? probably but i forgot my spanner wrenches at home so no go.

also with tunern00b running close to what you want to run caster wise he will have better advice than me. also keep in mind like he said...he uses it for autox and from the way he talked he doesnt do tracking events.

hope you are getting closer to your ideal setup!!

 

What I find weird is that people usually run LOWER caster angle in AutoX because of the low speed cornering and the need for a lighter steering.

Any idea on toe? Anyone?

 

lol. exactly. thats why i said listen to him. same chassis. i just dont know about the setup similarities.

and i guess noone else cares about your toes. lol.

 

But I like my toes...and they need caring, lol.

 

I run 0* toe, front and back, as my car is a double duty daily driver / auto-x car, and I can't afford excessive toe wear driving to/from work.

Toe is a personal preference. 0 toe is a nice compromise for most people. For auto-x use, a slight rear toe out can be beneficial for rotation. Slight front toe out can help turn in and responsiveness. On an overly loose car, some rear toe in can stabilize it.

Its one of those things you just need to play with to see what works for your driving style and your car's suspension/tire setup.

 

yeah to follow up on that. like i said before...start at 0 and go from there. who knows...you might like your car zero.d out.

 

I know for sure that having 0 toe in the rear does not suit my driving style. I am very smooth for corner transitions and whatnot, and when I had my toes set at 0/0 one time (goodyear did the alignment) the rear end was squirrely. I would hit a bump on a freeway entrance and lose the rear end. This was also running one of my favorite camber settings of -3.3/-3.

I guess I'll just have to grab some 8' pieces of pipe from a friend, adjust my toe until I like it, and get it aligned properly. I would rather have an expert tell me what either will do for me though, so I can see if what my seat of the pants feel is telling me the right thing (self tuning).

I am definitely going to run 1/16" rear toe in...I am just baffled by the front suspension settings...still.

 

i agree with starting at zero and going out. personally i run 1/16th out up front and between zero and 1/16th in out back. i've done as much as 1/8th out up front but it kills tires and becomes darty. also turn in is not really increased by anything i can feel at the wheel. i'm going to try 1/16th out up front and zero out back next.