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Can you throttle steer a FWD car?


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One of those uncommon days where I had reason to drive both the 2002 and minivan in quick succession and it got me thinking.  I've seen plenty of quick, well-driven Minis/Hondas/Focuses/etc. at several auto-x and/or track events, but I honestly don't understand how one drives a FWD car aggressively like that and now I'm really curious.  I mean, when I'm in one of my BMWs in a hard corner it's sorta second-nature to fine tune the car's attitude with some throttle input.  A small amount to just help push that nose in a little tighter or a healthier amount to get the tail to finish coming around while unwinding at the exit.  But when I do anything even remotely like that in the minivan (totally different animal, I know, but still) or my wife's car, then the front tires just go all mushy, lose grip, and I never feel like there's much I can do other than let off and just wait for the silly thing to find its feet again.  I don't mean at all uncontrolled mind you, not being a menace out there, this is just that split second thing when I'm one of my well-known corners but then reminded I'm stuck in the wrong car.  So how is it done differently in a FWD car? Again, I've seen plenty out there and know it can be done, but it must be fundamentally different somehow.  Is it all about a lot of trail-braking maybe? That's not something I do very much of, so might explain things a little. Help me figure this one out. . . 🤔

Edited by AustrianVespaGuy
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It makes a huge difference how the car is set up.  A rear wheel drive car you have the advantage of being able to exceed the available grip at the rear of the car by just adding enough power to spin the tires. With a front drive car you have to be able to do it by side loading the tires as much as you can and then using the throttle to transfer weight from the rear tires to the front.  There is a reason left foot breaking is more popular in front wheel drive cars. The serious autocrossers set their cars up very stiff in the rear to help balance the turn in. 

Edited by Preyupy
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I'm no expert, but I've been fooling around with a Saab 900 for the last year or so, and I've started to wrap my head around going quickly in it. In a nutshell, in FWD you steer the rear axle with the brakes. With RWD you're able to balance with the throttle in the corner to get the car pointed; with FWD, it's more about balancing with the brakes while using the throttle to pull the car through. For me, it usually boils down to pitching the car in to get the rear end moving (the Swedish flick is a real thing), getting into the throttle early, and hauling the car through (with left foot or handbrake as necessary, surface-dependent). It's very different than my autox experience in BMWs, but it can be quite entertaining, especially on loose surfaces.

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You most definitely can. 

 

Depending on how your suspension is setup, typically you lift/brake into a corner to unweight the rear and initiate over-rotation, then apply throttle to balance between pulling yourself thru and out of the corner while minimising understeer.

 

And yes, left-foot brake. 

 

This experience coming from being a goon in FWD cars thru highschool, and being an absolute terror on CA 152 Hecker Pass for years in a hand-me-down PT Cruiser, before I got an actual fast car. :)

 

 

Edited by 2002Scoob
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Good info, thanks guys!  Must take some pretty decent footwork to be able to quickly and smoothly transfer from a heel/toe downshift before a corner to left-foot braking for the corner, huh?  The physics is starting to get clearer though.  I think in my own driving 'style' I've always tended to focus on yaw rotation and not so much on the pitch of the car, but seems pitch probably becomes the more important dynamic for FWD. And that was one heck of a cool save in that race there Nick, wows!

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1 hour ago, AustrianVespaGuy said:

 tended to focus on yaw rotation and not so much on the pitch of the car,

 

Focused on yaw rotation through decreasing the grip in the back by spinning the tires, allowing the 'grip balance' to be biased to the front, letting the rear have less and rotate.  Well if that's the case, then lifting really hard on turn in would also cause a grip imbalance, no?  With way more grip from load (weight transfer from lifting, so way more normal force, so way more grip), the back has less because less load, lateral force already applied, car can rotate.  I've ever only tried a little- you have to really want to do it.

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when my car broke at one of the events and I got to drive someone FWD car, I quickly came to realization how much tyat car could rotate under breaking. what needed to happen in the tern is to start steering while under breaking and as soon as the car was getting close to loosing it, get on the throttle and drive it out. I changed the suspension on my car to get a bit of that feeling. 

 

Steve K. 

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There are probably better examples, but watch the Saab 96 at 6:36 in this video to see an instance of the Swedish flick I mentioned, the whole point of which is to unsettle the rear end before turning in. Note how the car rolls a bit, and the rapid back-and-forth of the front wheels before entering the corner.

 

 

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59 minutes ago, irdave said:

Focused on yaw rotation through decreasing the grip in the back by spinning the tires

Well I'm talking my lower-powered 2002 and E30 momentum cars, so I'm not usually breaking the whole rear end free, more of balancing steering and throttle input for attitude control after turn-in.  But that doesn't shift much front/rear loading in the same way brake modulation does!  I'm starting to think that's one of the key FWD vs. RWD differences now from this conversation.

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Quote

 

Depending on how your suspension is setup, typically you lift/brake into a corner to unweight the rear and initiate over-rotation, then apply throttle to balance between pulling yourself thru and out of the corner while minimising understeer

 

It's this.  If you youtube the BTCC, especially, to go fast a FWD car has to be set up to lose the rear end when you INITIATE

the turn aggressively.

Then when the fronts transfer grip to the rear under throttle, the car 'vector steers' (you pull the nose where you want it to

go with the front tires in full slip) and it drags itself in the direction you want it to go,

 

It is truly instructive to watch a gaggle of touring cars pile into a corner-

the FWD cars bump the RWD cars in the rear corners,

and they have to lose a TON of velocity to catch it, while the FWD cars just plant their throttles and fly by.

 

Since the cars have to be set up for transition oversteer, it's a lot harder to get a street car to go fast.

They just plow. because 'oversteer is dangerous' in the hands of 97% of your street drivers.

Now, unless you have an earlier Saab, the parking brake works on the rear wheels....

 

t

learned to drive in the snow in both FWD and RWD long before tracktions controlles....

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I used to auto-x my old Dodge GLHS. A mid-80s FWD 170hp turbo-4 hatchback econobox, lighter than an 02, it was stiff, easy to rotate and too-eagerly ate front tires. (2sets/year)

 

Like others have said: Brake while staying on the throttle, pre-roll to set, and hit it — the FWD would pull madly through the turn, the boost kicking up.

 

It was less than 2200lbs, but front heavy, so to avoid the aforementioned plow, you’d almost dart-turn it -- straight braking late but less, and then twitching and cutting a bit harder to induce the rotation and weight shift to pull-steer out. It wasn’t as smooth to me as RWD, but it sure got around cones quick.

 

With that car, the trick was hitting the boost right - it would kick-in real hard and spin the little gumballs a bit too easily. With FWD when they’re spinning too fast, you’re going where you used to be pointing quickly...

 

I started left-foot braking then, and using a handbrake, and actively using pitch & roll to help maneuver better - and have ever since. 
 

Tom-too

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