nlpamg

Thanks for the input, guys. Much appreciated.

Jooyoung99

Do you guys really get snap over steer? The back end gets loose pretty gradually to me.

I think the best advice I can give you is to go to BBI, 911 Design or GMG and get the correct alignment, corner balance and anti roll bar setup done. You can ask for a mild under-steer setup, which I like the best.

GT3 feels much more stable to drive when it's setup properly. I'm pretty sure Randy Pobst could've shaved 2 seconds off his lap at WSIR is the car was setup with mild under-steer.

vtracsd

I got my GT3 last week and anxious to try it out on the track vs my GTR. It'll be interesting to feel the difference. What do you do if you get into a corner too hot? I assume it's a no-no to lift off throttle and brake a little.

Manifold

That's a no-no in pretty much any car.

If too hot into a braking zone, keep the car straight, stay on the brakes, and use all of the track to slow down. That might be enough to keep you on the track and enable a rim shot, otherwise be prepared to go off, where you still might be able to control your trajectory (but keep the wheel straight when going off into gravel, etc., to avoid rolling the car).

If too hot while in the corner, you may be able to momentarily straighten the car, brake, and turn again. Otherwise, prepare to go two or four off in a controlled way.

The above scenarios are usually better than doing something which causes a spin, then crossing your fingers and hoping you don't hit something or something doesn't hit you.

This might be an opportune occasion to remind everyone that, sadly, an RLer has already died on track in his 991 GT3, so please be careful out there and stay within the limits of your driving ability.

fxz

+1000

Also from GT R AWD to RWD keep in mind that without nannies you could spin either exiting a turn!

Learn (easier because more gradually due a front end engine on a bmw)
how to manage rear oversteer that s a key factor for Any RWD

Laguna_Dude

once you get used to the dynamics and feeling the car.. you can start to do preventative inputs to negate any snap oversteer. first.. don't confuse snap oversteer with lift oversteer and/or power oversteer. snap oversteer is caused by the rear wanting to continue it's straight path while you are trying to turn (late-turn in to early mid-turn) and rotate the car.. this is the pendulum effect caused by the rear-engine weight bias.. this generally happens just before apex (when most turing/rotation occurs).. so the preventative input is to turn in crisply.. then once the car is pointed towards apex.. do a quick counter-steer input to initiate balance of weight onto the outer rear tire and inner front tire.. while doing this quick counter.. you start to get on the gas.. shifting weight to rear.. this is very handy in 2nd gear turns.. you can toss hard into the corner.. tap a counter steer and floor it and drive out of the turn with no snap.. just a controlled rotation... alway best to be in control vs. always waiting to respond or react to what the car is doing. also, better to be smooth in all inputs as to not disrupt the car.. 911's in particular are sensitive to this.

lifting oversteer is simply lifting off the gas during a sweeping turn disrupting the balance of the car, lightening the rear and causing abrupt oversteer.. this is hard to correct once initiated.. best to never fully lift but modulate gas to balance weight between front and rear.. a good example is turn 2 at big willow.. you never want to fully lift here.. but you can "throttle steer" by squeezing the gas causing the car to drift towards outside then slightly reduce throttle to bring it back in to inside.. this is key to maximize speed in sweepers.. but never lift off completely in sweepers.

throttle oversteer.. this is simply getting on the gas too early or too hard in a turn causing the rear to break loose.. the key here is stay on throttle and counter-steer... do not life once rear steps out.. that will cause the car to snap into a counter rotation and spin.. which is a very common thing with those with no experience controlling power slides.

another key is braking.. if you choose to not trail brake.. be sure to smoothly roll off brake.. as the lack of engine over front tires causes the front to lose grip on turn in after braking when the suspension decompresses..and will cause understeer. trail braking is best.. your brake point will be later and you carry the last part of braking during turn in.. which keeps the suspension compressed and maintains weight shift forward to enhance front grip allowing you to turn in faster vs. non-trail braking. it also helps in a more controlled rotation.

always best to squeeze brake hard and then roll off and onto the throttle.. this roll when done right and in a turn feels like the car is bending through the turn.

best is read as much as you can and practice.. iracing.com with a nice fanatec wheel setup allows you to practice at home and get muscle memory down.

fun2k

Not to hijack the thread but I have a question in regards to braking after turn in. Sometime I feel if that if I brake mid corner(to initiate a slight oversteer) at maybe 8/10th the car would simply try to understeer. Is that normal behaviour for all cars and not just rear engine 911s?

I know that when I lift off or brake at 10/10 its easy to make the car oversteer. Ive never tracked my cars yet

Laguna_Dude

generally speaking you should never brake after turn in.. you get all your braking done either before turning or into turn via trail braking. you have to imagine that when you brake, weight shifts forward.. lightening the rear and making front heavier.. thus making contact patch of tire smaller in rear and bigger in front..causing oversteer.. opposite can happen when on gas.. weight shifts back, making rear tire patch bigger and front smaller.. imagine that at static state (equal balance of weight), the normal tire patch has a finite amount of grip. this grip can be used to drive you forward (i.e. rear tires), slow you down.. or grip in turn.. if you are turning and 100% of tire grip is keeping the car planted.. once you brake or give it gas.. you will exceed the grip and cause whichever tires impacted to lose grip and slide.. like if you are powering out of a turn and still need grip to finish rotation, yet you give it too much gas.. you then exceed the rear tire's grip and cause power oversteer. if you brake mid-turn.. you lighten rear patch.. reducing finite traction available and if grip needed to maintain line exceeds this new smaller patch.. the rear will slide out.. same if you abruptly give it gas when needing to turn.. you make the front patches smaller.. reducing available grip and thus causing understeer.. there are other factors.. such as brake bias, LSD settings, suspension and alignment, how smooth or abrupt your inputs.. that all impact weight shift, tire patch, rotation, etc.. and it's dialing all this in that is the art of the game.

fun2k

Thanks, I understand the concept a little better now. But what confuses me is that, lets say there is a really long high speed curve and somewhere before apex your are at 8/10 limit of the car(well within tyre adhesion limit i.e) and when you press the brake pedal(lets say apply 30% pressure) the front starts to push instead of tucking in.

It feels as if there is uneven braking applied to all 4 wheels(maybe due to front brake bias??) or esc is intervening to induce safe understeer.

btw I have 14' gt3 with iron rotors.

Laguna_Dude

I would think ESC would only be triggered if it senses loss of control.. at 80% you are still well below losing control. I never use ESC or TC... so I have no idea there. but i would think since traction has NOT been lost, ESC and TC would not be triggered in this case. Also, you cannot have push/understeer without loss of front traction.. i.e. have not exceeded tire grip limit. The issue is that the car tracks straight when brake is applied. Because in a turn, grip of tires is fighting your prior momentum that was traveling in a straight line (before the turn). The grip used to slow the car is taking away from grip that was resisting that force; hence it cannot hold the same line and tracks out/straight. hope this makes sense. congrats on the GT3! and good call on the iron.. best feel and cheaper to replace and with proper pads and fluid can take a beating with no fade.

Kobalt

I think that when you brake and turn at the same time, the car want to go straight because of the dynamic forces in the car. (English is not my primary language, I hope that it made sense.)

I guess it is similar to braking with a motor bike when turning: the bike will straighten up so it is 90° compared to the ground and go in the direction of the tangent.


Maybe being much softer in the braking will make get you the expected behaviour?
Or maybe just ease of the throttle to get the car to turn around the apex faster.

Kobalt

As someone said: Be soft with all the controls.

Be gentle when you start applying the brakes - get pressure on the front wheels - then full brake.
When turning in - be gentle with the movements of steering wheel.
When getting of the brakes - do it smooth and gentle, don't upset the car.

Be nice to the car, don't force it to do things it don't like.

DChan415

On the GTR we had to push the 3 buttons up for 2 seconds, then go.

On the GT3, we have to turn the climate control off because it turns on by itself everytime. Then hit the exhaust button and go.

JRCNRING

Great thread, I'm taking delivery of my GT3 next Monday and already have the option on taking it to COTA at the end of the month.
I hope I can brake it in before then.

I agree entirely with what some one mentioned on the thread. To me the 911 will be a learning experience from scratch.

I have driven a GTR a few times on the track but I felt it had no real feedback from the car, It sort of felt the car was doing the work and I was just pressing the gas pedal.
I have the most time in my Challenge Stradale, which compared to the GTR is rear wheel drive and has less gismos to help the car.

I'm really eager to see how different they drive but at the same time a bit concerned on the prospect of fearing more the car on the track than enjoying it.

est8esq

Completely different car. Completely different feel.

Lines are lines (for most part w/ modest deviations), but entry, brake and exit are all very different.

The GT-R is just plain HEAVY. There's no carving into turns. It's a car w/ gross understeer, so you enter turns fast and hard w/ virtually no trail braking. You rotate the car quick and mash the gas pedal for the explosive turbos to kick in and head towards the next turn. It's very predictable. Very confidence inspiring and you get the learning curve rather quick.

For me, the GT3 is a different animal EVERY time I get behind the wheel? With each heat cycle of the tires, the ambient temps, the track temps, the pressure of tires, etc… seems like the car behaves just a tad different. If you figure it out quickly, you're rewarded w/ lap times you've never hit before. If not, then either you're slower or more critical events happen.

I feel for the weekend warrior doing a few track events a year, you're going to be quick faster in the GT-R and you're going to go home thinking you're a good driver. Then, going to the GT3 with some modest seat time, you'll simply smile at the GT-R owners and remember the first time you lost your virginity thinking how good you thought your made her feel and how good you "thought" you were?