Cost to track: Porsche vs BMW, chime in if you’ve upgraded

[adc]

Originally Posted by FormulaMMM

Got a quote pre-Sebring. I think it was $800 actually. Nope...

These are based on the agreed upon value of the car. For example for 2 days at Watkins Glen, OpenTrack wants $384 for my $65k estimated value M3 and $797 for a $140k 911 GT3.

If your quote was based on your M4 GTS, it is likely you used a replacement cost of around $140k.


I personally think that it is not worth tracking an M4 GTS, especially if you paid close to MSRP for it. Far better to start with a civic M4, and chuck away the suspension, brakes and seats as you suggested.

[NYG]

Originally Posted by CanAutM3

Not quite in that way.

While the CS is definitely faster than a civic around a track, the top speed it reaches on each straight is only marginally faster. I've got plenty of data log to compare my 2015 civic M4 to my 2019 M4cs that shows this, the CS is only a couple of mph faster at the end of long straights. It is in the corners and how it picks-up speed out of corners that it makes time. So one could even argue that the CS is less demanding on the brakes than a civic M3/4 because it needs to brake less going into turns .

And all that cooling in the straight is actually beneficial before that hard braking zone .

What? Marginally is a huge stretch especially at track speeds

Velocity contributes to kinetic energy by a square and weight contributes linearly.

Base (3625 lb) @ 100 mph = 1643 kJ
CS (3483 lb) @ 100 mph = 1579 kJ
CS (3483 lb) @ 102 mph = 1643 kJ

All I need is 2 mph from 100 mph to match kinetic energy of the heavier base model. That difference gets smaller and smaller the faster you go. I do an average of 8 mph more than my buddies zcp on the back straight of the Glen. If we brake to enter the bus stop at the same speed, I need to dissipate +305 kJ of non-conservative forces, where the majority is heat from friction.



Pair that with above, and the CS is SIGNIFICANTLY more demanding on brakes.

Since the CS is lighter and the weight reduction moves the center of mass towards the rear you end up with more understeer.

[Gomeler]

Pretty good discussion on things, in short, GT3 has a serious but warranted price premium over a F8x. Will be real curious to see what you think after a season with the car.

Can you opt for a 19" wheel setup, or are you stuck with 20/21 due to rotor/caliper? Haven't researched GT3 wheel sizing, but rubber for a 12x20 or 12.5x21 in the rear must hurt the wallet.

Originally Posted by FormulaMMM

I think the GT3 bucket with 3 pt is likely quite substantially more supportive than a Sportster + 3 pt.

And remember the 3 pt receptacle safety issues with any aftermarket bucket. Other than the OE Euro GTS seats, I'm not aware of any that integrate the receptacle properly like the GT3. I would not run a 3 pt with my Profi on track, for example. It's a legit compromise on safety.

I run with a .2 RS owner at the home track. He has a harness bar and 6 pt. Buckets and 3 pt are supportive enough that he typically doesn't bother with the hans and 6 pt. So just a bit of added weight... kind of funny.

I can't even comprehend having a 6 point + HANS available in the car and not using it on track.

[Powerslide]

Originally Posted by Gomeler

Pretty good discussion on things, in short, GT3 has a serious but warranted price premium over a F8x. Will be real curious to see what you think after a season with the car.

Can you opt for a 19" wheel setup, or are you stuck with 20/21 due to rotor/caliper? Haven't researched GT3 wheel sizing, but rubber for a 12x20 or 12.5x21 in the rear must hurt the wallet.

I can't even comprehend having a 6 point + HANS available in the car and not using it on track.

It's only for people who are VERY serious street drivers - LOL!

[FormulaMMM]

Originally Posted by adc

These are based on the agreed upon value of the car. For example for 2 days at Watkins Glen, OpenTrack wants $384 for my $65k estimated value M3 and $797 for a $140k 911 GT3.

If your quote was based on your M4 GTS, it is likely you used a replacement cost of around $140k.

I personally think that it is not worth tracking an M4 GTS, especially if you paid close to MSRP for it. Far better to start with a civic M4, and chuck away the suspension, brakes and seats as you suggested.

Right. In the quote form that I filled out it was agreed upon value for the GT3.

Originally Posted by Gomeler

Pretty good discussion on things, in short, GT3 has a serious but warranted price premium over a F8x. Will be real curious to see what you think after a season with the car.

Can you opt for a 19" wheel setup, or are you stuck with 20/21 due to rotor/caliper? Haven't researched GT3 wheel sizing, but rubber for a 12x20 or 12.5x21 in the rear must hurt the wallet.

I can't even comprehend having a 6 point + HANS available in the car and not using it on track.

Yeah, believe I can run 19's with the standard discs, but I'm a wuss and not messing with that system, or buying the viking style torque wrench that's required. Got the 911 with the understanding/hope that no mods are required for a few track days/year, so that's what I'm going to stick to. although they make these antigravity batteries that shed like 35 lbs min...

On the hans, just laziness, ha. I can sort of understand based upon how well the buckets and 3 pt manage, and after contorting myself to get into the GTS with helmet + hans on.

[CanAutM3]

Originally Posted by NYG

What? Marginally is a huge stretch especially at track speeds

Velocity contributes to kinetic energy by a square and weight contributes linearly.

Base (3625 lb) @ 100 mph = 1643 kJ
CS (3483 lb) @ 100 mph = 1579 kJ
CS (3483 lb) @ 102 mph = 1643 kJ

All I need is 2 mph from 100 mph to match kinetic energy of the heavier base model. That difference gets smaller and smaller the faster you go. I do an average of 8 mph more than my buddies zcp on the back straight of the Glen. If we brake to enter the bus stop at the same speed, I need to dissipate +305 kJ of non-conservative forces, where the majority is heat from friction.

Pair that with above, and the CS is SIGNIFICANTLY more demanding on brakes

My comment was meant tongue in cheek, but there is some truth to it. You are missing a key point of my argumentation: the higher corner entry speed capability of the CS.

Comparing data logs from my fastest laps between my 2015 M4 and my 2019 M4cs (over 2 second difference between the two done on the same tires) and zooming on the braking at the end of the back straight (biggest speed drop):

• Base M4 -> Top speed:229km/h -> Brake release speed: 120km/h
• M4cs -> Top speed:231km/h -> Brake release speed: 125km/h

Doing the math, the M4cs sheds 0.8% less energy in braking even when assuming the same weight for the two cars.

Like I said previously, experiences will vary, but in my case, I don't see my M4cs putting "SIGNIFICANTLY" more demand on the brakes than my base M4 did.

Originally Posted by NYG

I do an average of 8 mph more than my buddies zcp on the back straight of the Glen.

Since you are familiar with the Glen, my top speed a the Glen in my 2015 M4 was 245km/h (152mph) while my top speed in my 2019 M4cs was 248km/h (154mph). Not a huge difference...

Originally Posted by NYG

Since the CS is lighter and the weight reduction moves the center of mass towards the rear you end up with more understeer.

Different topic, but I am not sure why you conclude this, because usually moving the center of gravity to the rear reduces understeer by putting less stress on the front tires.

[Gomeler]

Originally Posted by FormulaMMM

Yeah, believe I can run 19's with the standard discs, but I'm a wuss and not messing with that system, or buying the viking style torque wrench that's required. Got the 911 with the understanding/hope that no mods are required for a few track days/year, so that's what I'm going to stick to. although they make these antigravity batteries that shed like 35 lbs min...

On the hans, just laziness, ha. I can sort of understand based upon how well the buckets and 3 pt manage, and after contorting myself to get into the GTS with helmet + hans on.

I've got one of the wrenches people mention on rennlist, I use it for axle nuts. You feel like you can rotate the Earth with that thing, it's around 4 feet long. I figure I'll likely end up with a GT3 RS, and I needed a bigger wrench for axle nuts so.. what's a few hundred bucks? Long-term investment in a GT3 RS

[FormulaMMM]

Originally Posted by Gomeler

I've got one of the wrenches people mention on rennlist, I use it for axle nuts. You feel like you can rotate the Earth with that thing, it's around 4 feet long. I figure I'll likely end up with a GT3 RS, and I needed a bigger wrench for axle nuts so.. what's a few hundred bucks? Long-term investment in a GT3 RS

haha it makes sense. Really, you had to for investment purposes.

[NYG]

Originally Posted by CanAutM3

My comment was meant tongue in cheek, but there is some truth to it. You are missing a key point of my argumentation: the higher corner entry speed capability of the CS.

Comparing data logs from my fastest laps between my 2015 M4 and my 2019 M4cs (over 2 second difference between the two done on the same tires) and zooming on the braking at the end of the back straight (biggest speed drop):

• Base M4 -> Top speed:229km/h -> Brake release speed: 120km/h
• M4cs -> Top speed:231km/h -> Brake release speed: 125km/h

Doing the math, the M4cs sheds 0.8% less energy in braking even when assuming the same weight for the two cars.

Like I said previously, experiences will vary, but in my case, I don't see my M4cs putting "SIGNIFICANTLY" more demand on the brakes than my base M4 did.

Different topic, but I am not sure why you conclude this, because usually moving the center of gravity to the rear reduces understeer by putting less stress on the front tires.

What if you're just improving your skills and have more confidence after 4 years?

Even if we assume a smaller magnitude for added thermal loads, remember that there's ZERO brake cooling on the F8x platform. You're continuously introducing thermal energy into a rotor/caliper/pad that has a higher initial temperature every time. At one point it gets too high.

Mass*, center of gravity isn't constant due to dampening/aero/etc.

Moving the center of mass to the back means less weight on the front tires, less weight means less grip specifically when you're talking about higher entry speed. That's why people correct understeer with more aero in the front.

[CanAutM3]

Originally Posted by NYG

What if you're just improving your skills and have more confidence after 4 years?

Nope, not related to experience or skill. There's less than a year elapsed between these laps.

Originally Posted by NYG

Mass*, center of gravity isn't constant due to dampening/aero/etc.

Moving the center of mass to the back means less weight on the front tires, less weight means less grip specifically when you're talking about higher entry speed. That's why people correct understeer with more aero in the front.

Nope. Center of gravity is pretty much a constant (except for the effect of fuel being consumed). The center of gravity is a static property of an object.

What you talk about is how dynamic loads are shared between the axles, the position of the Cg will affect load transfer, but load transfer does not affect the position of the Cg within the car. Aero also does not alter the position of the center of gravity either, it adds an outside load which does not need to be accelerated as part of vehicle mass.

Tire grip is also a complex matter, where grip does not increase linearly with normal load. The more load you transfer, the less total grip you have.

[nicknaz]

Originally Posted by CanAutM3

My comment was meant tongue in cheek, but there is some truth to it. You are missing a key point of my argumentation: the higher corner entry speed capability of the CS.

Comparing data logs from my fastest laps between my 2015 M4 and my 2019 M4cs (over 2 second difference between the two done on the same tires) and zooming on the braking at the end of the back straight (biggest speed drop):

• Base M4 -> Top speed:229km/h -> Brake release speed: 120km/h
• M4cs -> Top speed:231km/h -> Brake release speed: 125km/h

.

Nice data and thanks for sharing. I assume you are able to maintain that 3mph speed difference from brake release to corner exit. That’s massive.

[CanAutM3]

Originally Posted by nicknaz

Nice data and thanks for sharing. I assume you are able to maintain that 3mph speed difference from brake release to corner exit. That’s massive.

Apex speed advantage is a bit less (~2mph) but corner exit is actually a bit faster (~4mph). The CS is much better at putting the (added) power down coming out of corners.

[Laertes]

Originally Posted by SYT_Shadow

Meanwhile, the GT3 and GT3 RS guys all run with their nannies on, God forbid the car actually reacts to their cretinous inputs.

Sorry; haven't been following this thread for awhile, but I have to chime in here.

That's not an entirely fair statement. There absolutely are Porsche GT drivers that don't turn their nannies off because if they do they will die.

But the fastest, best drivers (National SCCA champs and such) ALSO leave their nannies on. Because the Porsche GT car stability control is amazing. I don't know how it works its magic, but it somehow knows the difference between a little intentional oversteer to get the car to rotate just a smidge more and an unintentional skid. I think its real skill is it understands weight transfer; you can move the weight of the car around without it freaking out.

When I had my 997.2 RS I had to turn all of the nannies off or they would kick in fairly frequently. It definitely improved if I made a conscious effort to be smoooooooth, but data showed if I did that I was slower. So I ran the nannies off, and I never had an issue without them.

Once you get to a certain level, the F82 is undriveable on the track without turning the nannies off. The stability control is so obtrusive the second you start to accelerate out of a corner the computer pulls the power and you just hear the engine note slow down like a sad trombone. I'm 3 seconds a lap faster at my local track (1:30ish lap, so a pretty short track) with the nannies off, and the car doesn't move around much at all when I turn them off, so it's not a matter of me overdriving the car.

The stability control on my 991.2 GT3RS, on the other hand, is completely invisible at the track. I've run with it on, and I've run with it off, and there is no difference in how the car feels and the data proves the car is just as fast. So why turn it off? If you really get out of sorts, no stability control will save you. But if I make a small mistake and it keeps me from wadding the car up in the armco, that seems a good reason to keep it on.

[SYT_Shadow]

Originally Posted by Laertes

The stability control on my 991.2 GT3RS, on the other hand, is completely invisible at the track. I've run with it on, and I've run with it off, and there is no difference in how the car feels and the data proves the car is just as fast. So why turn it off? If you really get out of sorts, no stability control will save you. But if I make a small mistake and it keeps me from wadding the car up in the armco, that seems a good reason to keep it on.

This is a pretty old thread, but if you're arguing that the 991.X Porsche stability control is very well done I completely agree with you.
The 991.X generation finally is fast and the electronic controls are the reason. It allows all kinds of cretins to achieve acceptable speeds at the track without receiving their due consequences, which is eating the wall.

It's funny that years ago the GT-R came out and was so criticized for allowing any form of cretin to be relatively fast. And now this is lauded as an advantage of what some people think is God's gift to driving: the GT3.

Personally I am happy the new stability controls are better. It brings a little excitement to chasing down 991 GT3s because if not I'd have to add another 400lb to my car or maybe use Michelin Energy tires.

Lastly, although the M3 stability control is not as advanced as others, a few weeks ago MDM allowed a 2:06.8 at WGI... which is the speed of the well driven 991.X GT3s.

[Laertes]

Originally Posted by SYT_Shadow

The 991.X generation finally is fast and the electronic controls are the reason. It allows all kinds of cretins to achieve acceptable speeds at the track without receiving their due consequences, which is eating the wall.

Ummm... no. The 991.x generation is fast for lots of reasons. Power. Aero (at least in the RS). Weight. Brakes. Weight distribution (gets the power down out of the corners). PDK. Etc. The nannies definitely help some drivers, but once you're experienced I don't think it makes you faster; it just gives you some security. I guess it's debatable whether knowing you're slightly less likely to put it in a wall makes you willing to push harder, but the fast guys are pushing so hard in those things the nannies aren't likely going to help much.

The traction control can help you get the power down without wheelspin if you're inexperienced and mash the throttle, but the cars have so much grip and are relatively low torque, and wheelspin in the dry on decent tires isn't an issue. Now that might be a totally different story in a GT2RS, but I've never driven one of those.

Look, I'm just as big of a fan of the F8x as you are. I love mine. And I've passed plenty of Porsche 991.x GT cars in my M4 (sounds like you have too). But saying the GT cars are fast because of the electronics is wrong and doesn't give credit to the other facets of the car. And in the same hands, they're faster than an F8x; at least one that hasn't been modified up the wazoo. But they should be given what they cost.

And what's with calling everyone cretins?

[SYT_Shadow]

Originally Posted by Laertes

Ummm... no. The 991.x generation is fast for lots of reasons. Power. Aero (at least in the RS). Weight. Brakes. Weight distribution (gets the power down out of the corners). PDK. Etc. The nannies definitely help some drivers, but once you're experienced I don't think it makes you faster; it just gives you some security. I guess it's debatable whether knowing you're slightly less likely to put it in a wall makes you willing to push harder, but the fast guys are pushing so hard in those things the nannies aren't likely going to help much.

The traction control can help you get the power down without wheelspin if you're inexperienced and mash the throttle, but the cars have so much grip and are relatively low torque, and wheelspin in the dry on decent tires isn't an issue. Now that might be a totally different story in a GT2RS, but I've never driven one of those.

Look, I'm just as big of a fan of the F8x as you are. I love mine. And I've passed plenty of Porsche 991.x GT cars in my M4 (sounds like you have too). But saying the GT cars are fast because of the electronics is wrong and doesn't give credit to the other facets of the car. And in the same hands, they're faster than an F8x; at least one that hasn't been modified up the wazoo. But they should be given what they cost.

And what's with calling everyone cretins?

It's an original word! Do you not like it?

I was saying the 991.x GT cars were fast comparing vs previous generations. The 997.2 has lots of the same things the 991 has, but lacks the electronics and subsequently is way slower. Quite difficult to drive as well.

[Laertes]

Having owned and tracked both, you are correct that the 991.2 3RS is definitely faster than a 997.2 3RS. I think it's hard to tease out exactly how much is due to what, but the majority is PDK vs. manual. That's the biggest part of the difference. And I guess you could consider that part of the electronics package, but I think it's just progress. Of course, there's also 70 hp more in the 991 and the car is the same weight. The front tires are a bit bigger for more front end grip, and there's no doubt the rear wheel steer helps dial out the understeer (ok. That's electronics too). And there's a big difference in aero (992 lbs vs. 359 lbs at 186 mph). But don't forget there's been about 10 years of tire development between the two generations. That makes a huge difference.

And I'm definitely faster in my F82 because of the DCT and advanced ECU that gets so many hp out of that little displacement. Don't those count as computers? And I'd argue that the folks driving E46s and E90s are probably frustrated by how much faster the F8x are, even in inexperienced hands.

All I'm saying is yes, a relatively inexperienced track driver can immediately be quickish out of the box in a 991 GT car. But if you want to be really fast, you have to know what you're doing.

[SYT_Shadow]

Originally Posted by Laertes

All I'm saying is yes, a relatively inexperienced track driver can immediately be quickish out of the box in a 991 GT car. But if you want to be really fast, you have to know what you're doing.

I think we completely agree.

[MyFragileHalogen]

This thread was very informative and educational! Now I understand a lot better about 'em.

I would think when there is a bit too much ego involved in track days where there is no trophy for nobody, things get a bit interesting with some overly inefficient usage of those GT3 cars; and people will love to talk about driving skill and cost efficiency! Last track day I (new thing I learned personally but nothing new to y'all) saw a track prepped E90 (but that is still driven to track with tires carried) doing a well driven GT3RS time. Don't even need a F8x to get the job done! GT cars no doubt are amazing and when I see some novice/intermediate people bringing them out I am happy for them.

I guess if there is a much cheaper car than BMW F8x that can still keep up or outperform at track, they would be saying similar things though.

[gum2012]

Originally Posted by MyFragileHalogen

This thread was very informative and educational! Now I understand a lot better about 'em.

I would think when there is a bit too much ego involved in track days where there is no trophy for nobody, things get a bit interesting with some overly inefficient usage of those GT3 cars; and people will love to talk about driving skill and cost efficiency! Last track day I (new thing I learned personally but nothing new to y'all) saw a track prepped E90 (but that is still driven to track with tires carried) doing a well driven GT3RS time. Don't even need a F8x to get the job done! GT cars no doubt are amazing and when I see some novice/intermediate people bringing them out I am happy for them.

I guess if there is a much cheaper car than BMW F8x that can still keep up or outperform at track, they would be saying similar things though.

Hah exactly. It’s just like people playing golf. Trying to get their swing down as much as possible to win absolutely nothing. The best driver is the one having the most fun and it’s not really debatable. We only do this to have fun because lord knows it’s expensive as hell .

[adc]

Originally Posted by MyFragileHalogen

This thread was very informative and educational! Now I understand a lot better about 'em.

I would think when there is a bit too much ego involved in track days where there is no trophy for nobody, things get a bit interesting with some overly inefficient usage of those GT3 cars; and people will love to talk about driving skill and cost efficiency! Last track day I (new thing I learned personally but nothing new to y'all) saw a track prepped E90 (but that is still driven to track with tires carried) doing a well driven GT3RS time. Don't even need a F8x to get the job done! GT cars no doubt are amazing and when I see some novice/intermediate people bringing them out I am happy for them.

I guess if there is a much cheaper car than BMW F8x that can still keep up or outperform at track, they would be saying similar things though.

Assuming you’re in the market for a 4 seater, I think the Camaro SS 1LE has at least parity with the F82, performance wise. If you need 4 doors though, there is nothing else.

I don’t consider a 911 a 4 seater.


And you have personal likes and dislikes thrown in. I positively hate the Camaro interior and visibility issues. Some people can easily afford a 911 (bit of a stretch for me) and they love the driving feel (steering, brakes, cockpit, etc), and consider picking one over a BMW a non event.

None of these things have anything to do with track lap times, driving skill and confidence to push. It’s a complex equation.

[MyFragileHalogen]

Originally Posted by adc

Assuming you’re in the market for a 4 seater, I think the Camaro SS 1LE has at least parity with the F82, performance wise. If you need 4 doors though, there is nothing else.

I don’t consider a 911 a 4 seater.


And you have personal likes and dislikes thrown in. I positively hate the Camaro interior and visibility issues. Some people can easily afford a 911 (bit of a stretch for me) and they love the driving feel (steering, brakes, cockpit, etc), and consider picking one over a BMW a non event.

None of these things have anything to do with track lap times, driving skill and confidence to push. It’s a complex equation.

I agree E90 & F80 are the freakin' 4 door saloons that are really the all around best. Not looking the best (IMO ) but now I get the point of having 2 extra doors! Maybe Alfa Romeo Gulia? but it doesn't have the proven record of reliability and vast resource we have.

Then 2 door cars- E92, F82, and E46; still plenty of space and can get very fast. I don't see that many Camaro drivers here so I have no knowledge. It's really hard to think of a car that can get up to GT3 speed without it trying to kill you or grenade itself (you now Miata and S2000 and such ) I wonder if a stripped out STI with a rebuilt motor can get that fast? Maybe not GT3 fast?

There's nothing wrong with having money to buy a GT3RS and have fun driving it at track. I think it's mostly about people who drive them who may deserve criticism, but not the car itself to be blamed. Though probably it brings a chance of building more ego as it could be taken as a shame to be slower than other while driving one of those.
I've met some good people and car lovers who respect when they saw a cheaper car passing them; like walking over to my car and starting a friendly conversation ("It's MANUAL!?") to exchange information and talk about cars.