The official MP4-12C Thread

I think it will be relatively easy to get wheel/tires for track use....just need to know the correct offset and you can get lots of folks to build you good quality two or three piece track wheels that will hold up. Agree we'll have to go to smaller diameter wheels to use true track tires. One reason I stayed with 16" on my old 911 racer was to be able to get the biggest selection of tires....that was a few years ago though and there are more options for bigger wheels. That being said, I think 18's will be a good alternative. I am sure some manufacturers are already looking into this and drooling at the prospects of selling wheels to those of us who just have to play hard at the track.

I would think the steel rotors and race pads would be the way to go. The car is light enough (yeah, it's all relative) for the 4-piston rotors and pads to handle the heat as long as you use true racing pads and racing fluid. The stock 430 brakes were smaller on a heavier car and with race pads it was pretty good on the track....I upgraded to Brembo GT's and it did make a huge difference is stopping power due to increased swept area with bigger calipers and pads...but again, by using racing pads it's easy to take the heat and you can use different compounds at each end to help balance the car under braking, although I'm guessing that will be less of a problem with the 12C.

Lovely to think about the possibilities!!

 

A no brainer option,over 20Lbs saving at the wheels would need 120lbs weight reduction elsewhere in the car to equal the performance gains!

 

Hi August, Welcome & again thanks for the info. It confirms much of what I have read on Mclaren's OS, and various other articles.

I'm not sure if you have read andy_c's post stating the Iconel exhaust systems weight advantage is now only 1kg. Is your info direct from Mclaren or from internet/magazine sources?

 

Agree

One thought crossed my mind though. I'm no engineer, and may be miles off base here, but I do wonder if Mclarens use of hydraulic suspension to control wheel movement would negate this somewhat in real world conditions?

Either way less weight, especially unsprung weight is always a good thing.

 

Hah! I *WISH* I was ordering one!

I have a good friend who is getting one and he's provided me some of the info he's received. The 3kg is what he was told by McLaren (but I don't know if the dealer told him or if he got that from McLaren directly - it's not from a magazine/blog/internets, however). The wheel weights came from the options .pdf (which I'd post but is too large, apparently).

I've been a McLaren fan since I was 5 and used to watch them kick butt in CanAm (reverent moment of silence for one of the greatest racing series EVER)...

 

They aren't using the hydraulics to control wheel movement, they are there to replace the mechanical anti-roll bars. Reducing unsprung weight is just as beneficial on this car. And saying a 1 pound reduction of unsprung weight equals a reduction of 6 pounds of sprung weight is kind of a silly generalization, it's kind of like saying "a sandwich has 800 calories". What kind of sandwich, and how big? If the weight reduction in a wheel occurs near the hub it is not nearly as beneficial as that same weight reduction would be moved away from the hub. Besides, the 1=6 generalization applies only to acceleration and braking parameters, not the more important suspension-compliance parameters. Reducing wheel weight makes a car handle better and feel better. Besides, what's another $5K for the lightweight wheel option?

 

Good enough for me...

 

Did you guys see Steve Sutcliff's comments on the new Lambo compared to the Macca? (he, he, he, now I can show off with the easy access to Autocar):

How does it stack up beside the new McLaren?
Not too well in theory, but fine in practice, b/c it's a completely different car to the McLaren. One that's nowhere near as well resolved dynamically, but offers a more extrovert driving experience...

 

Well then, if you want to use integral calculus to determine the weigh distribution of a cars wheels and then do some simple calculations to determine the equivalent mass increase to the car, you will find the real number approaches a 2 to 1 ratio and not the 6 to 1 (or even 10 to 1) you hear on the internet. But, people want to believe the bigger numbers.

p.s. Don't count all your sandwiches as 800 calories either.

There really is a huge choice of fantastic cars today. The McLaren probably has capabilities far beyond what 75% of the new owners will ever come close to exploring.

 

Most detailed explanation that I've seen of the 12C's dampers yet--under the heading "Proactive Chassis Control":

http://www.caranddriver.com/reviews/car/11q1/2012_mclaren_mp4-12c-first_drive_review/tech_trickledown_page_2

 

i think the inconerl exhaust was 3 to 4 kilos lighter originally,your comment about the iris system will add a bit 3 speakers go to 7 speakers,but as you would expect they have gone to MCLAREN lengths in finding the lightest metal possible for the magnets in them,this will be the lightest sound system in a car,just like the F1

 

I posted it earlier, but the best detailed overview of the suspension is here:
http://blogs.insideline.com/straightline/2010/09/2012-mclaren-mp4-12c-suspension-walkaround.html

 

I really can't decide if standard brakes or CCBs will be best for a car that will see track work. McLaren seems to be pretty consistent in saying that the CCBs are intended for track driving, however I guess there is no way to predict the durability of the Brembo setup. If it is Ferrari quality, then I would probably pass. If it is more like Porsche kit, then I'd take it. At the speeds this car is capable of, it sure would be nice to have CCBs.

I understand the standard brakes are by AP Racing, which is great. However, I bet replacement rotors are still going to be expensive, vs. aftermarket.

Anybody have any further thoughts?

 

I explicitly asked the factory (through dealer) about brake replacement costs. Still waiting for answer.

 

Me too.
I read on the Porsche forum that replacement cost for CCB rotors:

Corvette ZR1: $5K / set
Porsche: $16K / set
Ferrari: $30K / set
Bugatti: $50K / set

However, the rotors from Brembo are virtually identical for all these cars.

 

It's not as clear cut: ccb's will last 3-4 times longer on th track than steel and will not lose any braking power till they go. Yes, they are bigger, but that means you will get better braking out of the car. The car is very fast and can get up to very big speeds.

 

in the evo mag Chris Harris has said the 0-300 kph ime is 24.5 seconds,nothing quicker this side of a veyron,head line is The MP4-12c is the best sports car-perhaps the best road car of any description-i have ever driven.with the ride quality better than a 5series,high praise indeed, ps,will try to find out the replacement cost of steel rotors next week

 

For those that missed it, RG's blog is back up on Evo website.

http://community.evo.co.uk/users/Roger-Green/blogs/index.cfm/2011/3/2/ROGER-GREEN-The-new-McLaren-isnt-soulless

In many of the reviews of the MP4-12C the major criticism levelled at it has been that there’s a shortfall in emotional connection. Fair comment? I don’t think so. Certainly not compared with the 458, which relies more on history and association with truly epic Ferraris like the Enzo or any of the GTOs rather than creating its own aura. Yes, the Ferrari has more visual allure, but soul? A 360 Stradale has a bucket-load more than a 458. Make no mistake, the current entry-level Ferrari will prickle the nape of any petrolhead and its capabilities are unquestionably extraordinary. But it's the McLaren that really got under my skin – and it’s even more able.

As you can read in the new issue of evo, on sale today, it took all of six laps of a wet and bumpy Llandow track to understand how obsessively engineered this car is. These conditions presented just about the toughest test you could subject a supercar to, and yet in the Mac you instantly felt secure. It keys into the tarmac, dismissing bumps and standing water, and it builds confidence so fast you can really lean on it within a lap. it is shockingly fast too. I knew it would be quick – Monkey told me in no uncertain terms as I climbed aboard, and, like everyone else, I’d already seen the acceleration figures – but that knowledge still doesn’t prepare you for the full effect.

But the most astonishing aspect isn’t the power, it’s what the MP4-12C does with it. Over the soaking wet, cold Welsh moorland roads the ride was almost spooky. I opted for ‘Sport’ in those conditions to tighten the roll rate, but it still had an exceptional level of suppleness, connectedness and feel. It’s a true drivers’ car. You feel instantly at one with it, and yet you also know that each and every drive would uncover more facets. It’s not a car to show off in. It’s a car to drive, and in the real world conditions there’s nothing faster or more accomplished. Seventeen years ago McLaren re-wrote the supercar rule book. I reckon they’ve just done it again.

 

pps dont forget ,they will probably wear more evenly than any other car because of the airbrake making the back brakes work nearly as hard as the front

 

Ever driven? Wow. I wonder if he penned that before his last video. Either way, that is crazy praise, especially considering the accolades he and the rest of Evo staff gave the 911 GT3 in PCOTY.

The new issue hasn't come out on ipad yet. I feel shafted.

 

not that good with computors,thing LAZERBLU will be able to come up with this, for you guys across the pond

 

We heard the 0-300 rumor before, but it's still extremely hard to believe. Here some comparison times:
20.7 - Bugatti 16.4 Veyron (Handling-mode, no High Speed-Key)
28.6 - Porsche 911 GT2 RS
32.3 - Lamborghini Gallardo LP570-4 Superleggera (458 Italia: 32.4)
35.4 - Corvette ZR1
42.2 - Mercedes-Benz SLS AMG
50.6 - Lexus LFA 54.3 (to 280 km/h)
54.3 - BMW M3 GTS
http://www.6speedonline.com/forums/attachment.php?attachmentid=130895&d=1282357086

Outright speed-wise, this car is much closer to Veyron than to Italia or any other possible competitors. Again, insane!

 

Steel rotors are cheap....I don't care WHAT car they are for. The steel rotors for the 12C are made by AP, and they will be using a standard size. I have purchased steel rotors for all kinds of high and low end cars, and the prices are not dependent upon the type of car unless you buy from the dealer. I would anticipate that you will be able to buy steel rotors (the aluminum hats don't need to be replaced when you replace the rotors) for all four corners for under $1000, certainly for under $1500. Heck, racing PADS might be more expensive than the rotors! I've done this many times for Ferrari's and Porsches, and the 12C will not be any different. And those of us who plan to track the car will be buying pads all the time...again these will be standard calipers and pad sizes. Nothing particularly exotic about steel brakes, folks. Very easy to replace. Those of us who have tracked cars a lot can change a set of pads in a few minutes (assuming the calipers are design with the usual Brembo/AP-type springs to allow for quick access for changing pads) and certainly a full set of rotors and pads in between our run sessions....it's that easy once you've done it a few times. The most time consuming thing is usually getting out the tools and jacking up the car and taking off and replacing the wheels. The 12C is stiff enough (as is the F430 and the 911 GT3, etc.) to be able to jack up one side of the car at a time, so you won't have to do each corner one at a time. Also nothing magical about bleeding the brakes, etc. Really, you can even change your own oil on a modern Ferrari with no problems....it just takes time because you have to remove/replace under-trays.

Truly nothing too exotic about these basic maintenance items. You just have to be careful not to over-tighten things when dealing with aluminum calipers and aluminum blocks, etc.

That being said, I wouldn't go near the hydraulic suspension bits on a car like th 12C....THAT is certainly better left to trained mechanics.