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12-03-2008, 10:44 PM | #1 |
JDM Fred
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cornering help
I've noticed when I've been taking hard left or right turns the car bogs down and seems like all the weight is shifted to the front tire of the direction of the turn. Seems like my suspension just bogs down and the car kind of just looses momentum.
I think it's the suspension and now I'm wondering if the tein coilovers might be too soft and bog down also. Also I'm wondering if it has to do with my winter tires and maybe having an auto transmission
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1990 Mazda Miata... I miss my Yaris |
12-04-2008, 12:02 AM | #2 |
ULTIMATE
Drives: 07 Yaris Turbo Join Date: May 2007
Location: Canoga Park, CA
Posts: 14,859
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are the coilover adjustable for stiffness and/or pre-load?
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12-04-2008, 12:28 AM | #3 | |
QUACK~!!!!!
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Quote:
if i remember correct when my bf had his civic, it's the next best thing compared to front sways
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" ... I don't follow, thus i reign SUPREME . The only time i follow is when i follow my dreams ... " |
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12-04-2008, 12:59 AM | #4 |
JDM Fred
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I'm stock, except a center brace, on the underside of the car. I go from 3rd 60mph+, downshift to 2nd while braking and the back slides a bit and then it just bogs onto the left or right corner and it feel like it looses tracktion as I exit the turn. I figured coilovers would help alot but I know nothing about racing other than how to take a turn and rev matching.
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1990 Mazda Miata... I miss my Yaris |
12-04-2008, 02:37 AM | #5 |
QUACK~!!!!!
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sounds like it could be your tires
the back slides out??? i'm not sure about that ... try out the h-brace and see if that helps with anything, and then maybe look into different tires since you are riding on your "winter tires" not sure what kinda tires they are using but it might just mainly be your winter tires
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" ... I don't follow, thus i reign SUPREME . The only time i follow is when i follow my dreams ... " |
12-07-2008, 11:15 PM | #6 |
Reluctantly Crouched...
Drives: 2008 Yaris HB M/T Join Date: Oct 2008
Location: DFW, TX
Posts: 867
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I'd say this is a combination of non-performance tires, under-inflation (for performance purposes) and carrying too much speed into the corners. When I autocross my stock yaris, I had the same problem at first, but tweaking the tire pressure up to 38 F and 34 R along with carrying less speed into the corner allowed me to accelerate out of the corners without the "plowing" effect I think you're describing.
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12-08-2008, 11:14 AM | #7 |
Drives: Yaris Join Date: Oct 2008
Location: Michigan
Posts: 199
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You are defiantly going to fast for your setup. More air pressure and stiffer suspension will help, but you will still always have a limit where this behavior happens.
I would also suggest braking hard just before the corner and be back on the throttle slightly(or moderately depending on the turn and where your apex is). Accelerating will help push the front up, but you'll have obvious grip limits so don't gun it too much. The key is to practice and get a feel for how the car handles with different entrance, apex, and exit of corners at different speeds. |
12-08-2008, 02:59 PM | #8 |
DKDC
Drives: Yarlet Join Date: Aug 2006
Location: los angeles
Posts: 200
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one easy thing to remember: braking pushes your car's weight to the front and accelerating sends the weight to the back (not so much in a stock yaris). depending on how much and when you break going through a turn will shift the weight around. this shift will cause number of fun things to happen, like over/under steer depending how you control your car. learn to control the "weight shift" and you will see improvements no matter what your set up is.
tires, suspension, and breaks will improve the way your car feels but not the way you drive. |
12-22-2008, 11:23 PM | #9 |
Ecurie Snoopy Lives
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And remember, to brake before you turn. When the weight shifts to the front, the rear lightens up. At the track we always tell people to go in slow and out fast. Meaning to brake before the turn and slow enough so the car doesn't understeer.
The other thing when you are braking and turning, this is where the rear shifts to the outside and you end up with (off throttle) oversteer. You'll have to learn the limits a bit better in these cars, because with stock tires, it's easy to meet those limits and you may end up where you don't want to. If you rear does brake loose, ease off the brakes and countersteer quickly to reset the car. Learn to use the throttle and steering to help get the control back quickly. This and all of the above posts should help you out. A great place to learn all of this is the auto x. And it's fun!
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12-23-2008, 03:06 AM | #10 |
What?
Drives: 2007 Yaris LB Join Date: Nov 2008
Location: Safety Harbor, FL
Posts: 1,006
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There's a mix of good and bad advice being given here, but most of it is good. The height of the bad is the notion that you need a larger front swaybar. That's the last thing you want on a Yaris, especially if you're already experiencing oversteer.
The simple fact is that you're over-driving the car. Things like "brake first, then turn" and "slow in, fast out" are the best advice presented here. Getting the back end loose in your Yaris should be the exception rather than the rule, and it should NEVER happen on the street. Period. If you want to drive that aggressively, get into autocross, or go find a race track. The front end "loading up" as you make and exit the turn is a combination of the fact that you're probably still on the brakes when you begin the turn (which is why the back end is coming around), and you're being too agressive with the throttle. You can feel the inside tire spinning, and beyond that, you can feel the outside tire push outward... both of these are signs that you're giving the car too much throttle for the amount of grip you have available. (either due to road conditions or crappy tires) The solution is to ease off of the throttle and/or reduce the steering angle until the front tires regain their traction. In a FWD car, don't even try to go full throttle on corner exit until you have the wheel almost completely straight. Ideally, you want to get all of your braking done BEFORE the turn. Begin the turn with neutral-throttle, then complete the turn under light-to-moderate throttle and add more throttle as you unwind the wheel. It's easier said than done, but that's what it takes to get around a corner fast. Sounds like you have a Tein coilover kit. There are some things you can do (setup mistakes that you can correct) that may help. They may seem counterintuitive to you, but here they are: 1. Make sure you're not set TOO low. Too low can mean you're cornering on the bump stops. When you hit the bump stops, your spring rate goes from whatever it should be to near infinity. If this happens in the rear first, you get oversteer. (and it can be really nasty snap-spinning oversteer) If it happens in the front first, you get understeer. So, don't "slam" the car. Leave yourself a little bit of suspension travel. Suspension travel is more important than wheel gap! 2. Stiffer is not always better. What are your shocks set to? (if you have Tein Basic, you have no damping adjustment) Full stiff is really only good for super-smooth surfaces, the kind of surfaces you rarely encounter in the real world. A suspension can only work (work = absorb the imperfections of the road so that the tire stays in contact with the road) if you let it, there needs to be some compliance. Aside from that, you can use the shock adjustments to help adjust the balance of the car. For instance, if you just can't ditch (poor word choice?) the tendency for the back end to step out, you might try softening the rear shocks relative to the front to make the back end more forgiving. 3. Tire pressures are important. Not only should they be higher than "normal" for the kind of driving you're talking about, but like shock settings (and spring rates, and sway bars), they can be used to help adjust the balance of the car. Going REALLY high with the rear pressures can induce oversteer in an autocross environment if you need it. It does so mainly by increasing the "effective spring rate of the tire", but depending on the tire, it can also reduce the contact patch of the tire. Going lower in the rear can help it stick better and stay planted. For street use, you should be running about the same as the front, or up to 5-10 psi less. On a FWD car, front tire pressures can't be tweaked as much. They have a lot of weight on them, and take a lot of the cornering load, so they need to have fairly high pressures. You'll find that there is a minimum pressure below which the tread will roll over and you'll scuff up your sidewalls. Stay above that. But, usually any more than maybe 10psi more than that won't gain you anything but a really harsh ride. Okay, enough rambling. Have fun, but be safe. Lots of families on the road this time of year. Concentrate on smoothness and proper racing line. You don't have to drive fast and out of control to practice these things! But, if you ALWAYS drive smoothly, and ALWAYS drive a racing line (within your lane, of course), you'll learn habits that will be there for you when you get to a track or an emergency situation where you NEED to be fast. You'll also soon learn that you can actually corner faster without all the drama. |
12-23-2008, 08:27 AM | #11 |
l33t3st Asshole
Drives: MY07 Yaris Liftback Join Date: Nov 2006
Location: Epcot
Posts: 588
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first things first, don't buy any parts.
first thing to do is re-learn aggressive driving for your current setup, if you continually over push your car you will never learn to be fast. Start Slow get faster, then once you hit the "too fast" (scrubbing speed b/c of over/understeer) dial it back a little. Before you buy any performance parts buy new tires. Tires are the most important thing for a car and if you cheap out on tires your performance will suck as well. The best coilover/swaybar/bracing suspension will still suck when on cheap tires. oh and get out there and AUTOX! Don't be acting a fool on the streets. |
12-23-2008, 08:52 AM | #12 |
daily driver
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smooth driving = key
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12-23-2008, 02:41 PM | #13 |
it is due in largest part to your tires. basically you are generating more cornering force then your tires like to handle causing a large slip angle... deforming the tires... and the more they deform the less "happy" they are to reform to their shape and continue forward...
The coilovers are part of it, but the largest part is due to the tires and wheels |
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12-23-2008, 09:06 PM | #14 |
rarer than JDM -1 of 1!
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Agreed. Practice driving "the proper line" when ever you are in the car. It doesn't mean acting a fool on the interstate, but knowing the line. Setting yourself up to take a turn is also just as important if not more important than trying to "buy" handling. JDM/aftermarket coilovers don't mean jack if you can't handle your car in stock trim.
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12-23-2008, 11:09 PM | #15 |
Drives: 07 Yaris sedan Join Date: Jun 2007
Location: Keremeos BC
Posts: 986
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Good ol' Loren, always lays it out the way it should be. Smooth is definitely the key here. I have seen lots of jockeys out there, slamming onto the pedals and steering, thinking they are going great, lots of tire smoke, yadayadayada, with crappy times.
Jackie Stewart said it best: a passenger should never be able to tell exactly when you applied brakes, throttle, or steering, it should all be on smooth motion. What else is there to say? Some guys out there spend yards of money on equipment when the fact is that they can't drive worth squit. Practice, guys, particularly on slick surfaces like sand or such, and LEARN what the fastest way is around a course, even a corner. |
12-24-2008, 04:33 AM | #16 |
Parallel Parking Pro
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I was going to write a long essay about cornering, but I decided to just say, buy a Playstation 3 and Gran Turismo game. Earn your licences, and get an idea of cornering lines.
Next, when winter thaws out, have a go with some mates racing go-karts. It is the cheapest safest and best way to learn about racing lines, and have some fun along the way.
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12-24-2008, 04:57 AM | #17 |
vroom vroom
Drives: lil red 5-door Join Date: Sep 2006
Location: Bangkok, Thailand
Posts: 7,744
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yes! Took me like 5 hours to get the S license in GT3, gave me a good appreciation of the importance of smoothness And turn off the stability assists, they make things too easy!
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12-24-2008, 12:01 PM | #18 |
Drives: 07 Yaris sedan Join Date: Jun 2007
Location: Keremeos BC
Posts: 986
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Hm. I suppose the Playstation will show you the lines alright (never having tried it), but the stability aid required most is the ass of your pants: EVERY mistake makes itself felt there! Practice, guys, practice...
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