[kyrix1st]

Originally Posted by baron95

Lap times are interesting, but I care more about how the tires held up (and brakes) - would love to see pictures of the front tire shoulders - and how the car feels on track to drive.

Track days are all about having fun while going through consumables (tires, brakes, etc) at an acceptable rate.

The P-cars are great for the consumable wear rates. Don't expect the M2 to match that, but having a set of pads last at least 2 full weekends and tires last a few is a plus.

100-200kg difference is huge on consumables. To give you an idea...
I went through 10 track days over a year on my Z3 1.9, haven't changed the pads, rotors or tires during that time. On my E92 M3, I changed pads, rotors and tires after 3-4 track days of similar intensity.

I changed the brake fluid on both of them whenever I felt the pedal get spongy/every 6 months. As for the engine oil, I kept it at 1,000km or 100 running hours.

[baron95]

Originally Posted by kyrix1st

100-200kg difference is huge on consumables. To give you an idea...
I went through 10 track days over a year on my Z3 1.9, haven't changed the pads, rotors or tires during that time. On my E92 M3, I changed pads, rotors and tires after 3-4 track days of similar intensity.

I changed the brake fluid on both of them whenever I felt the pedal get spongy/every 6 months. As for the engine oil, I kept it at 1,000km or 100 running hours.

Not to derail the thread, but the Z3 1.9 was sold in the US? Given that I occasional race Spec E30, I'd have loved to track a low HP street bimmer. I didn't know the 1.9 were sold in the US.

[shawnhayes]

Originally Posted by kyrix1st

100-200kg difference is huge on consumables. To give you an idea...
I went through 10 track days over a year on my Z3 1.9, haven't changed the pads, rotors or tires during that time. On my E92 M3, I changed pads, rotors and tires after 3-4 track days of similar intensity.

Are you joking?

You're comparing weight as the contributing factor on consumable rate in cars with a 300hp power differential?

Look, one of my favorite things to do is tool around VIR with one of my buddies in a spec Miata in my M5. He's very clean and FAST around the turns. I consume 15% of the same amount of fuel, and very little tire wear or brake pad wear. But the difference is speed and acceleration, nothing to do with weight.

You can't compare those cars consumable rates and attribute it to weight. Those cars don't live on the same planet as far as acceleration, top speed, and resultant braking delta.

I don't controvert that weight doesn't have a contribution. But that's not the major contributor in that case.

Shawn

[zinner]

Great thread, I love VIR and reading your comments about driving the track takes me back there.

[shawnhayes]

Originally Posted by zinner

Great thread, I love VIR and reading your comments about driving the track takes me back there.

Come back. Lots of open events there. You're just a hop skip and a jump away.

Shawn

[kyrix1st]

Originally Posted by shawnhayes

Are you joking?

You're comparing weight as the contributing factor on consumable rate in cars with a 300hp power differential?

Look, one of my favorite things to do is tool around VIR with one of my buddies in a spec Miata in my M5. He's very clean and FAST around the turns. I consume 15% of the same amount of fuel, and very little tire wear or brake pad wear. But the difference is speed and acceleration, nothing to do with weight.

You can't compare those cars consumable rates and attribute it to weight. Those cars don't live on the same planet as far as acceleration, top speed, and resultant braking delta.

I don't controvert that weight doesn't have a contribution. But that's not the major contributor in that case.

Shawn

Not exactly.. my Z3 cornered faster than the E92 M3, it's a momentum car. What it lacks in straight line you make up by not losing speed in corner entries. Tire wear is primarily weight, anyone who says otherwise hasn't tracked their lightweight cars hard enough.
If what you are saying is true, Caterhams should consume tires at a much more rapid pace than Miatas but that's simply not the case. Uneven wear is mostly alignment issue.
I would agree brake and rotor wears are more power dependent.

Originally Posted by baron95

Not to derail the thread, but the Z3 1.9 was sold in the US? Given that I occasional race Spec E30, I'd have loved to track a low HP street bimmer. I didn't know the 1.9 were sold in the US.

No, it was my race car back in Japan. JP spec had the best car, I think the final gear ratio was 3.8, not offered anywhere else in the world. I raced with an FIA grade A (national) competition license.

[shawnhayes]

Originally Posted by kyrix1st

Not exactly.. my Z3 cornered faster than the E92 M3, it's a momentum car. What it lacks in straight line you make up by not losing speed in corner entries. Tire wear is primarily weight, anyone who says otherwise hasn't tracked their lightweight cars hard enough.
I would agree brake and rotor wears are more power dependent.

I’m not saying that weight isn’t a factor, it’s not the primary factor. Lateral wear could be, but in braking and acceleration it’s horsepower. Put 500 hp in a Miata and matt the accelerator and tell me that the wear (and tire smoke) is due to the light weight of the Miata.

Shawn

[zinner]

Originally Posted by Kroghj1

Stock, my money would be on the g87 based on the number of camaros passed over the weekend.

Most Camaros at Chin events are the LS with the V6 .

Edit this is sarcasm as chin events tend to bring out the fastest drivers in my limited experience.

[aerobod]

Originally Posted by kyrix1st

If what you are saying is true, Caterhams should consume tires at a much more rapid pace than Miatas but that's simply not the case. Uneven wear is mostly alignment issue.
I would agree brake and rotor wears are more power dependent.

As a Caterham R400 owner and my son having owned several Miatas and comparing with my old Z4M, there isn’t a lot of difference in tyre life. Overall 1500km / 900 miles of track day use seems to be about average to a tyre set down to the cords, it is just the Caterham 13” tyres tend to be a bit cheaper.

I also get very even tyre wear with the 185/60-13 front and 235/45-13 rear tyres on the Caterham with the aggressive camber and toe settings, although about 20% more life from the rear tyres than the fronts.

If the tyres are getting to the same temperature and slip angles are the same, then tyre life will be comparable between the cars, as the heavier car tends to have a wider tyre.

[kyrix1st]

Originally Posted by aerobod

As a Caterham R400 owner and my son having owned several Miatas and comparing with my old Z4M, there isn’t a lot of difference in tyre life. Overall 1500km / 900 miles of track day use seems to be about average to a tyre set down to the cords, it is just the Caterham 13” tyres tend to be a bit cheaper.

I also get very even tyre wear with the 185/60-13 front and 235/45-13 rear tyres on the Caterham with the aggressive camber and toe settings, although about 20% more life from the rear tyres than the fronts.

If the tyres are getting to the same temperature and slip angles are the same, then tyre life will be comparable between the cars, as the heavier car tends to have a wider tyre.

That's actually right on point with what I'm saying. Caterhams make 400ps per ton, while Spec Miatas make around 160ps per ton.

If tire wear were primarily power dependent, Caterhams would show much more tire wear than Spec Miatas which isn't the case. Your testimony adds to that.

[aerobod]

Originally Posted by kyrix1st

That's actually right on point with what I'm saying. Caterhams make 400ps per ton, while Spec Miatas make around 160ps per ton.

If tire wear were primarily power dependent, Caterhams would show much more tire wear than Spec Miatas which isn't the case. Your testimony adds to that.

The Caterham is also half the weight of the Spec Miata, so the tyre wear being the same shows that it is not directly related to weight overall.

The brake wear on the rear of Caterhams can be quite high, though, with performance pads lasting about the same as a set of tyres (about half a dozen track days), even though the caliper is the same as used on cars 3x the weight, the upgraded AP front brakes and pads have one-tenth the wear of the rear brakes, though. Another wear factor that doesn’t necessarily directly correlate with weight.

[kyrix1st]

Originally Posted by aerobod

The Caterham is also half the weight of the Spec Miata, so the tyre wear being the same shows that it is not directly related to weight overall.

The brake wear on the rear of Caterhams can be quite high, though, with performance pads lasting about the same as a set of tyres (about half a dozen track days), even though the caliper is the same as used on cars 3x the weight, the upgraded AP front brakes and pads have one-tenth the wear of the rear brakes, though. Another wear factor that doesn’t necessarily directly correlate with weight.

Like I said, you and I are saying the same thing.

If R400s weighed 1 ton (the same as spec Miata), its tire wear will definitely be higher. The reason it doesn't, is because it weighs half as much.

I did mention brake and rotor wears are higher with more power, because you need higher Mu to decelerate the car.

[aerobod]

Originally Posted by kyrix1st

Like I said, you and I are saying the same thing.

If R400s weighed 1 ton (the same as spec Miata), its tire wear will definitely be higher. The reason it doesn't, is because it weighs half as much.

I did mention brake and rotor wears are higher with more power, because you need higher Mu to decelerate the car.

We are not overall in agreement. You said “100-200kg difference is huge on consumables”, I’m saying not necessarily, otherwise the Caterham would have higher tyre life than the Miata. Also, the high powered Caterhams tend to wear the front tyres out before the rears (20% faster in my case) and also wear the rear brakes out 10x faster than the front (which have very long life, even though the tyres don’t).

[adc]

So can we not scare the OP away with all this armchair racing, and perhaps let him answer a question or two based on his own experience in an M2?

[shawnhayes]

Originally Posted by adc

So can we not scare the OP away with all this armchair racing, and perhaps let him answer a question or two based on his own experience in an M2?

Funny. But the criticism of the current M2 being too heavy MUST be addressed. I drive an M5 CS on track. I KNEW walking in what it was going to be like. I LOVE LOVE LOVE this new M2, but it suffers from the same ills mine does. It is what it is.

Nonetheless, cool car, cool track, nice story. I was there with him. It was an ABSOLUTE BLAST (even if I corded my Pilot Sport Cup2's)

Shawn

[shawnhayes]

Originally Posted by zinner

Most Camaros at Chin events are the LS with the V6 .

Edit this is sarcasm as chin events tend to bring out the fastest drivers in my limited experience.

And some absolutely stunning hardware. For the signup, for the Red Group, I stopped counting the hardware expense for the cars after I got to $2 million. And that was just for eight cars.

Shawn

[vrooooom]

is that mechanical detent switch still on BMWs? I have the F87 manual and it doesn't have that.

[shawnhayes]

Originally Posted by vrooooom

is that mechanical detent switch still on BMWs? I have the F87 manual and it doesn't have that.

Manuals don’t have it. It’s 0-100% throttle. The detent is to let the whole car know maximum acceleration (thus “kickdown” as well). Manuals depend on the nut between the steering wheel and the back of the front seat to control that.

Shawn

[leftfootbr8king]

@kroghj1 can we get some run group/lap time details? It would give a lot of context and would be nice to change the subject away from the current debate happening in this thread.