BRZ as daily driver?

[ashtray]

Actually, thinner tires may work better, depending on the type of snow you get. I would probably just get the stock size. +/-1 size wouldn't make much difference as each manufacturer's tire specs vary slightly in their actual width even though they might all be 215/45's.

[OrbitalEllipses]

Skinnier tires for winter is the norm. On my WRX I run 225/45/17 in the summer and 205/50/17 in the winter, though I could go to a 205/55/16 if I wanted to.

[Corey]

Originally Posted by Draco-REX

Rule #1 of circuit racing works well in the real world too. Especially when conditions get bad.

"Always do ONE thing at a time." You can Turn, Brake, or Accelerate. But only do one at a time. Your tires only have so much grip, and you have to spend it like money to buy what you want to do. If you try to do two things (turning while accelerating) you'll have to spread your money out and have less for either.

Well this isn't entirely bad advice for someone new to driving in poor conditions, this is a fundamentally flawed way to drive on a circuit. In fact spreading your "money" out over two things, let's call it diversifying your investments, actually produces a higher net total. In simple words modern tires actually provide more total grip in a given combination of lateral and longitudinal forces than they do in any one situation. This is often illustrated through a "grip circle".


image borrowed from http://farnorthracing.com/autocross_secrets3_5.html (good further reading)

The circle represents the point at which the tire will begin to slide. Anywhere within the circle and you are ok. Anywhere outside of the circle and you are likely not. This provides a simple visual way to understand a tire's grip. For example, at 100% acceleration you've reached the maximum total grip of the tire; any turn of the steering wheel will cause understeer. However, follow the perimeter of the circle to a point at 75% acceleration. While you'd perhaps expect to be able to corner left/right with the "remaining" 25%, the reality is quite different. The tire is actually capable of generating about 75% of its maximum cornering force WHILE accelerating with 75% of its accelerating force; a far higher total amount of grip than simply using 100% for acceleration.

The implication of this is to get the best use of your tires it's ideal to be producing both lateral and forward/backward force at the same time, or in other words both cornering and accelerating/braking. This is exemplified by racing techniques like trail braking and early entry lines (which allow earlier acceleration) that combine the two forces.

Queue "the more you know" music..

[Mr.Jay]

Originally Posted by LSxJunkie

I daily drove my G35 and both of my GTOs. 400hp, RWD, stick. A good set of tires and you're golden. You'll actually stop and turn better than those idiots who go screaming past you at 70mph on the highway in the snow just to end up upside down in a ditch 3 miles later.

Looks lonely out there

We get some crazy snow sometimes here in Vancouver and I still plan to DD. Like what has been repeated snow tires are key

[BillY2KFRC]

Originally Posted by LSxJunkie

Ohaithar.

GTO (and CTS-V) was near the top of my new daily driver list until the BRZ caught my eye. In the end I wanted my 2nd car to be a completely different driving experience from my Vette. Figured the GTO may feel too similar. I'm guessing it's fun hopping between the GTO and G35 for similar reasons.

[Draco-REX]

Originally Posted by Corey

Well this isn't entirely bad advice for someone new to driving in poor conditions, this is a fundamentally flawed way to drive on a circuit. In fact spreading your "money" out over two things, let's call it diversifying your investments, actually produces a higher net total. In simple words modern tires actually provide more total grip in a given combination of lateral and longitudinal forces than they do in any one situation. This is often illustrated through a "grip circle".


image borrowed from http://farnorthracing.com/autocross_secrets3_5.html (good further reading)

The circle represents the point at which the tire will begin to slide. Anywhere within the circle and you are ok. Anywhere outside of the circle and you are likely not. This provides a simple visual way to understand a tire's grip. For example, at 100% acceleration you've reached the maximum total grip of the tire; any turn of the steering wheel will cause understeer. However, follow the perimeter of the circle to a point at 75% acceleration. While you'd perhaps expect to be able to corner left/right with the "remaining" 25%, the reality is quite different. The tire is actually capable of generating about 75% of its maximum cornering force WHILE accelerating with 75% of its accelerating force; a far higher total amount of grip than simply using 100% for acceleration.

The implication of this is to get the best use of your tires it's ideal to be producing both lateral and forward/backward force at the same time, or in other words both cornering and accelerating/braking. This is exemplified by racing techniques like trail braking and early entry lines (which allow earlier acceleration) that combine the two forces.

Queue "the more you know" music..

I'm quite familiar with the grip circle, both inside and outside. However the "Do one thing only" advice is how you *start* training someone for performance driving. You're correct the "trail-braking" and "rolling into the throttle" are necessary for fast track times. But judging how to balance two of the three forces comes with experience. So you start someone doing *one* thing at a time. This is doubly important to hammer home to a new track head because in their day-to-day lives they have been able to brake and accelerate in the middle of a corner with impunity and so have picked up bad habits.

My post was about driving in poor conditions however. While on a sunny day the average driver will probably never find the outer limit of the grip circle, on wet and snowy roads it's very likely. So in poor conditions track techniques meant to help budget the grip circle become very effective for the average driver.

I'm not telling him how to drive on a track, but how to keep his new RWD car out of the trees.

[LSxJunkie]

Originally Posted by BillY2KFRC

GTO (and CTS-V) was near the top of my new daily driver list until the BRZ caught my eye. In the end I wanted my 2nd car to be a completely different driving experience from my Vette. Figured the GTO may feel too similar. I'm guessing it's fun hopping between the GTO and G35 for similar reasons.

I remember you were considering a CTS-V the last time I saw you. The GTO would have been very different, but on stock suspension, it would've been more like driving an LS2 land barge. Amazing grand tourer, would soak up hundreds of miles in a day in comfort, but certainly not tossable and nimble like this will be. Going from the G35 to the GTO to the GTO with shocks, springs, bushings and sways, I kept finding that I wanted even more power but I REALLY missed the sharp steering. The woefully slow steering ratio killed it, and the only fast ratio rack was expensive, built in very limited quantities, and was apparently a bit leaky. Plus the rear was made of glass. I suspect you'll have none of these problems with the BRZ though.

[Turbowned]

On my 9th New England winter, 7 of which were driven with a RWD car. The best years were the ones with RWD + snow tires. The worst years were any with all-season tires, FWD or RWD. The most interesting year was this one, with AWD + summer tires.

I'm glad the BRZ is coming with all-seasons. That gives me two pairs of rear tires for drifting, as I plan on having a dedicated set of summer and winter wheels/tires for the car

Although I plan on modding the BRZ, I think I'll make my MR2 a dedicated track car and leave the BRZ for fun cruising and the occasional drift event because drifting my MR2 is too much of a challenge.

[serialk11r]

But they're not all seasons...

[ashtray]

Exactly - BRZ COMES WITH SUMMER TIRES!.

[Canibuz]

Originally Posted by Turbowned

On my 9th New England winter, 7 of which were driven with a RWD car. The best years were the ones with RWD + snow tires. The worst years were any with all-season tires, FWD or RWD. The most interesting year was this one, with AWD + summer tires.

I'm glad the BRZ is coming with all-seasons. That gives me two pairs of rear tires for drifting, as I plan on having a dedicated set of summer and winter wheels/tires for the car

Although I plan on modding the BRZ, I think I'll make my MR2 a dedicated track car and leave the BRZ for fun cruising and the occasional drift event because drifting my MR2 is too much of a challenge.

This...

I drove a MR2 around in winter with all seasons sometimes fun sometimes scary. Everyone in the NE that drives a rwd or hp car knows either drive extremely careful or get dedicated tires for summer/winter. Town fair tire usually has a extremely crazy deal going on right around august. Its usually 4 snow tires with stealies for 4-5 hundred. I can't remember the brand but even the worst snow tire is better in the snow than a all season tire.

[fatoni]

Originally Posted by Corey

Well this isn't entirely bad advice for someone new to driving in poor conditions, this is a fundamentally flawed way to drive on a circuit. In fact spreading your "money" out over two things, let's call it diversifying your investments, actually produces a higher net total. In simple words modern tires actually provide more total grip in a given combination of lateral and longitudinal forces than they do in any one situation. This is often illustrated through a "grip circle".


image borrowed from http://farnorthracing.com/autocross_secrets3_5.html (good further reading)

The circle represents the point at which the tire will begin to slide. Anywhere within the circle and you are ok. Anywhere outside of the circle and you are likely not. This provides a simple visual way to understand a tire's grip. For example, at 100% acceleration you've reached the maximum total grip of the tire; any turn of the steering wheel will cause understeer. However, follow the perimeter of the circle to a point at 75% acceleration. While you'd perhaps expect to be able to corner left/right with the "remaining" 25%, the reality is quite different. The tire is actually capable of generating about 75% of its maximum cornering force WHILE accelerating with 75% of its accelerating force; a far higher total amount of grip than simply using 100% for acceleration.

The implication of this is to get the best use of your tires it's ideal to be producing both lateral and forward/backward force at the same time, or in other words both cornering and accelerating/braking. This is exemplified by racing techniques like trail braking and early entry lines (which allow earlier acceleration) that combine the two forces.

Queue "the more you know" music..

you make sense but accelerating force and accelerating grip are two different things. you may accelerate at 75% of what the engine can provide wile cornering with 75% lateral grip but you cant accelerate at 75% of what the tires can handle while cornering with 75% lateral grip. yeah sometimes it is advantageous to combine both from time to time but i assume for any given line, the person who stays closer to that circle is faster regardless of what parts of the circle they are using

[Corey]

Originally Posted by fatoni

you make sense but accelerating force and accelerating grip are two different things. you may accelerate at 75% of what the engine can provide wile cornering with 75% lateral grip but you cant accelerate at 75% of what the tires can handle while cornering with 75% lateral grip. yeah sometimes it is advantageous to combine both from time to time but i assume for any given line, the person who stays closer to that circle is faster regardless of what parts of the circle they are using

The engine's power is actually entirely irrelevant as long as it can provide enough power to use 100% of the tires' traction during perfectly straight forward acceleration. Note that this is very often not the case, as in my own car which is on wide sticky tires with only a meager 150hp. That "actual" grip circle for such a car would look smushed on top because the engine simply can't produce enough power to use much of the tire's potential forward grip.

What you're saying is exactly what one would expect, but the truth is tires are not so simple. Let me illustrate it this way:



The red lines I've drawn in illustrate what you'd guess represents a tire's grip: a linear relationship between lateral and longitudinal grip. This would represent a car that can either accelerate/brake at 100% without cornering, corner at 100% without accelerating/braking, or do some combination of the two in which the two forces always add up to 100%, i.e. 50% acceleration and 50% left cornering. This is not how tires work.

You can see there is overlap between between the "expected" lines and the actual grip circle at the four extreme forces. At those four points the maximum potential of the tire is the same. The interesting parts are the diagonal areas that represent a combination of lateral and longitudinal forces. The area within the circle but outside the "expected" lines represent the higher potential grip of the tire when combining forces. At any point in that area up until the outer limit of the grip circle you are using more of the tire's potential, and will thus produce faster lap times, than someone who operates only within the "expected" lines. Indeed, the combination of forces in those areas will add up to a greater net force than the maximum the tire can produce in any one direction. In other words using techniques like trail braking that use both lateral and longitudinal grip at the same time will produce more grip, and thus better lap times than someone who only "does one thing at a time."

[UAM]

This car will be the company DD car. We will take the z34 and E90 and weekend cars.