Road course Toe alignment?
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Well.... I used to run a very autocross-like 1/8" toe-out, but that can be a bit wiggly under braking.
These days I've been running pretty much straight up zero toe. Feels predictable and I don't need to move the wheel so much while braking.
These days I've been running pretty much straight up zero toe. Feels predictable and I don't need to move the wheel so much while braking.
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It would depend on how stiff your suspension set up is and if you have an LSD, also how big the track is, and how well a track matches your skills.
With stock sway bars (poly bushings or not), and with camber still in the stock range (even though nearer to the max end of range), I use very minimal rear toe-in (.1 per side) and .05 per side toe-out up front. The toe-out up front is close enough to being straight during acceleration that rolling resistance is minimized, and the car will hold a slight drift in carrousel (when maintaining entry speed), and is easy to force the rear around under late braking. The front is more "live" with toe-out, less dead-straight-fingertip-steering like it is with toe-in or even zero toe. I like a tiny bit of rear toe-in, because the car catches itself in a squat around sweepers like that, and if you are on a course large enough to have those, it's very nice when you don't have an LSD.
IMO, if you have an LSD and are at the lowest point you can get to and still have at least a tiny bit of FLCA travel that isn't just removing neg camber up front (Eibach Pro springs or adjustable coil-overs), then you still want a bit of toe-out up front, but you can probably get away with more toe-in at the rear, and exit faster using the rear end's active nature, digging in while the LSD pulls the car around. But you could probably also get away with less toe-in at the rear, because the LSD will make up for certain sins, and you won't need the rear end to be as forgiving. That said, it really depends on your driving propensities/style... are you smooth/deliberate in transition or abrupt/attacking (rhetorical)?
With stock sway bars (poly bushings or not), and with camber still in the stock range (even though nearer to the max end of range), I use very minimal rear toe-in (.1 per side) and .05 per side toe-out up front. The toe-out up front is close enough to being straight during acceleration that rolling resistance is minimized, and the car will hold a slight drift in carrousel (when maintaining entry speed), and is easy to force the rear around under late braking. The front is more "live" with toe-out, less dead-straight-fingertip-steering like it is with toe-in or even zero toe. I like a tiny bit of rear toe-in, because the car catches itself in a squat around sweepers like that, and if you are on a course large enough to have those, it's very nice when you don't have an LSD.
IMO, if you have an LSD and are at the lowest point you can get to and still have at least a tiny bit of FLCA travel that isn't just removing neg camber up front (Eibach Pro springs or adjustable coil-overs), then you still want a bit of toe-out up front, but you can probably get away with more toe-in at the rear, and exit faster using the rear end's active nature, digging in while the LSD pulls the car around. But you could probably also get away with less toe-in at the rear, because the LSD will make up for certain sins, and you won't need the rear end to be as forgiving. That said, it really depends on your driving propensities/style... are you smooth/deliberate in transition or abrupt/attacking (rhetorical)?
So the car setup is pretty much road course set. Running Terrible's old coilovers. Which are around 515 up front and 616 in the rear with the stock front 21mm bar and the H&R 24mm rear bar. Im about as low as the suspension allows in a racing setup. I also have a torsen LSD.
It seems like 0 toe up front should be a good place to start as things are more wiggly/darty than I want right now. Havent gotten to the track yet, but if its like this now I imagine it will be worse on track.
Can you explain a bit more how rear toe works on the focus suspension? Im going to do more reading tonight. My alignment guy gets bent out of shape when I tell him something other than the "factory" .15 out on the rear, but he will do as I request if I push it.
It seems like 0 toe up front should be a good place to start as things are more wiggly/darty than I want right now. Havent gotten to the track yet, but if its like this now I imagine it will be worse on track.
Can you explain a bit more how rear toe works on the focus suspension? Im going to do more reading tonight. My alignment guy gets bent out of shape when I tell him something other than the "factory" .15 out on the rear, but he will do as I request if I push it.
So the car setup is pretty much road course set. Running Terrible1's old coilovers. Which are around 515 up front and 616 in the rear with the stock front 21mm bar and the H&R 24mm rear bar. Im about as low as the suspension allows in a racing setup. I also have a torsen LSD.
It seems like 0 toe up front should be a good place to start as things are more wiggly/darty than I want right now. Havent gotten to the track yet, but if its like this now I imagine it will be worse on track.
Right now there is about .15* out in the rear too, which feels pretty okay, but i will likely have the shop align that in to 0* aswell. and see how things feel.
It seems like 0 toe up front should be a good place to start as things are more wiggly/darty than I want right now. Havent gotten to the track yet, but if its like this now I imagine it will be worse on track.
Right now there is about .15* out in the rear too, which feels pretty okay, but i will likely have the shop align that in to 0* aswell. and see how things feel.
+.15 is the factory "spec" but yeah for track im going to bring it into zero. I had some problems with off-camber 5-6 at gingerman last year in the wet. The back end was super lively. In the dry it just felt on edge the whole time.
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Positive numbers are toe-in. Factory for SVT is 0.08 to 0.23 per side in the rear. Getting closer to zero in the rear will make the rear end come around more easily... oversteer... toe-out in the rear would be a nightmare of instability, with the car jumping from side to side at every bump.
The way the stock rear works is when the outside side collapses due to cornering forces, the arms and flex blade (trailing arms) cause the outside wheel to toe in and negative camber to increase slightly. [Like a running back planting their foot when making a quick direction change to avoid tackle.] It fights against oversteer.
When you stiffen the suspension too much you loose this function, which may be a wanted goal in some applications to help the car rotate instead of plow, but there is a limit. Also, when you lower it too far, so that the LCAs (front or rear) are parallel with the ground, you will increase static negative camber to the max point, so when you turn and collapse the suspension more, you will actually loose negative camber and loose the mechanical handling functions of both ends of the car.
IMO, it's not best-practice to remove ALL compliance from a Focus rear suspension. It has an excellent, driver friendly geometry that can be ruined much easier than improved upon. A little body roll (the kind that's hard to see, but still there) is actually a very good thing on a Focus. A lot of body roll is, of course, not optimum due to enacting too much nanny understeer, and just making the driver uncomfortable. Eliminating almost all body roll compromises all the effectiveness of the Focus' wonderfully engineered suspension, and would be like driving a tubular frame car that weighs half what the Focus does, and needs to be trailered everywhere... will make you go around the course slower than you could otherwise.
For competition, predictability is your best friend, so poly bushings are good, keeping a bit of rear toe (minimal) is good, keeping a bit of front neg toe (out), or zero toe with an LSD, is good... just as much as braking the same amount at the same time and choosing the same gear and apexing at the same point and accelerating with the same determination each time for each corner are all good. Don't try to outguess the engineers who designed the thing. Use the Focus, Luke.
Ah got my numbers backwards about understanding rear toe. I may leave rear toe then and see how it feels, but the front really has some toe issues at high speed. So pushing that in is needed.
As for the suspension mods affecting things. I do have massive toe arms and camber arms, poly trailing arms and stock LCAs.
As for the suspension mods affecting things. I do have massive toe arms and camber arms, poly trailing arms and stock LCAs.
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IMO, .31 total (~.15 per side) is a good number. Right in the middle of the range, 0.15 to 0.45 total toe. [I really enjoyed 0.12 per side in my old Focus sedan w/SVT suspension, w/all poly adjustable arms, and -1.5 camber each side.]
Front total toe is spec'd at -0.30 to 0.00, max -0.15 per. So you are right in the middle of it. Since you are not at the high side on the rear and you have LSD, you might enjoy getting closer to zero front toe, as Omni suggests.
Front total toe is spec'd at -0.30 to 0.00, max -0.15 per. So you are right in the middle of it. Since you are not at the high side on the rear and you have LSD, you might enjoy getting closer to zero front toe, as Omni suggests.
All the info supplied has been spot on. Not knowing the power output of your car remember rotation with the rear requires you the driver to be ready to power out of the slight rotation. Drifting is fun, not fast but fun. Running with stiff bar and the coilovers allows the lowering to work. The alignment that works for our track car is more camber, 2.3-2.5 neg in the rear and zero toe. It works with a massive rear bar and no front. I don't like a twitchy rear and the focus rear end stays planted and secure at pace. The only thing we are fighting is rear brake lockup on the unweighted inside tire. We also found that the same inside tire will actually lift off the ground and carry around the corner no more than 2" but clearly showing air.
Its still just a stock SVT gearbox, I end up being in 3rd most of the time.
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Intake/exhaust/tune as I remember.
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I don't think you'll notice much of a difference at all in the way the car behaves, the benefits are more for feel than anything else.
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