Mr.E.G.

Ooh, ohh, pick me.



I follow GT2 cars pretty closely. Let's use the ALMS cars as our test sample.

With the exception of the E92 BMW M3 GTR, which is a goddamn travesty in my opinion, all of the cars use a legitimate production chassis. However, there are several different types of chassis in the series so allow me to delve into that.

The most appropriate answer to your question of whether or not they start as showroom cars and then get turned into race cars really depends on the car in question, and which racing season we are referring to.

The 911 GT3 RSRs that are in the series are bought from Porsche ready to be raced. They effective start life as a body in white race car (called body in white because they come as just the bare chassis with white paint or primer). The unibody is identical to any other 911 that you would get from the dealer, only it comes with a rollcage installed by the manufacturer. Porsche's racing division effectively is the equivalent of a tuner shop that then turns that body in white into a race car. They build several versions that are tuned to varying degrees for varying classes. Every year or so they make tweaks so that the previous year's model may become obsolete, but I will try to break it down based on what the current versions are, so forgive me if I get some overlapping versions in here by mistake.



911 GT3 Cup
The first level is the 911 GT3 cup. It is gutted (technically, interior is never added), has racing electrics installed, and has fairly conservative body work that is based off of the production 911 GT3 including the 911 GT3 production car's front bumper with an integrated airdam. The 911 GT3 cup also has composite doors, a sequential transmission, lexan windows, a rear wing with aluminum supports, single lug hubs, slick tires, and big brakes. The unibody is entirely uncut. The dampers and springs are obviously upgraded, but the suspension configuration and the control arms, subframes, etc. are all stock with exception of upgraded bushings in several spots. Another point worth mentioning is that the front side radiators duct through the wheel wells just like the production 911s and the center radiator ducting is the same as the production car as well. I point this out because it is this way on the lower versions and different on the highest variant.

The 911 GT3 Cup car is obviously designed to race in the Porsche 911 Cup series (a one make series) but is also ready to race in the GT4 class, one of the Grand Am classes (I forget which one), and in the Speed World Challenge, although the WC cars are slightly more so upgraded and they run on street tires. Some people will race the 911 GT3 Cup in club racing classes and in GT3 classes, even though it is probably outclassed in most of the European GT3 classes without some modifications. I would also argue that it is a bit too much car for the GT4 classes, but that's debatable.



911 GT3 Cup S
The 911 GT3 Cup S is basically the same thing only it has the wider body work similar to that of the production 911 GT3 RS. The engine is also slightly more powerful, but other than that it is basically the same. It is designed to race in the GT3 class.



911 GT3 Cup R
The 911 GT3 Cup R is basically the same thing as the cup S (it has actually superseded the Cup S) but it now has very wide bodywork almost as extreme as the 911 GT3RSR. It has a conventional rear diffuser with vertical strakes.



911 GT3 RSR
The 911 GT3 RSR is at the top of the food chain. It is designed to race in the GT2 series. It is everything that the above mentioned cars are only with a more powerful engine, a bigger aerofoil, incredibly wide body work, bigger brakes, etc. It is essentially just a more aggressively tuned version. The suspension configuration is the same as stock. There are spherical bearings all around and the swaybars are blade-type and cockpit adjustable. The car has a flat underbody and has a rather modest diffuser with no vertical strakes (per the rules in GT2). One of the most significant aspects of the GT3 RSR is the front end aero. To the untrained eye, the car has no discernible front splitter. However, the radiator inlet in the front actually allows air to pass through a network of ducts that vent through the side, in front of the wheel wells. The central radiator ducts through the hood (the older versions duct through the small slit between the bumper and hood just like the production 911 GT3, but the new versions now duct through the hood about halfway back). This ducting esentially creates an integrated splitter that is internal to the front bumper. The front end also has canards nestled into the area around the radiator inlets. This is a recipe for downforce, and a damn good one. The aero packages is quite a bit more extreme and everything is dialed up a couple of notches over the lesser variants.

I provided the examples of the lesser 911 racing models because I think that in order to appreciate the GT2 level of the 911 (the 911 GT3 RSR), you have to be able to appreciate the lineage. It truly is a modified production car, it just so happens to be modified by the manufacturer. If you bought a 911 off of the showroom and gutted it, caged it, developed an aero package and upgraded all of the go fast components, you would end up with the same car, only probably much much slower. LOL. The unibody 911 with its 6 cylinder engine and less sophisticated suspension is certainly a knife at a gun fight, yet they win so consistently and I think that the primary reason for this is because there is such a wealth of knowledge behind the cars. There are more 911s racing in GT series than any other car and all of that knowledge can be leveraged into a winning package.



The Ford GTR that races in the ALMS GT2 series is made from a showroom car that was turned into a race car. This car has an aluminum space frame chassis (easily most sophisticated car in the series) that is identical any other Ford GT. The suspension configuration is the same as the production car. Naturally, all of the suspension components have been upgraded.


The Corvette C6-R (Not the old GT1 version, but the GT2 version) is similar to the Porsche in that it is tuned by the factory and is made from cars that never made it to the showroom, but it uses a production chassis. The Corvette gets a little more wiggle room though because what is considered to be a chassis by the ALMS is anything that can't be unbolted (that's a bit of a watered down explanation). The Corvette has a pretty minimalistic chassis with body panels that are removable from the chassis. However, it's not quite that simple. The Corvette also has sub assemblies that the body panels bolt to which are composite from the factory. Since they unbolt, they are allowed to be replaced as well. So you have the basic backbone chassis with carbon fiber support structures in place of the fiberglass structures from factory, with all carbon fiber body work on top. The suspension uses the factory subframes and obviously has custom control arms, swaybars, etc.



The Ferrari F430GT is a also built by Ferrari but it also uses the same chassis that a showroom f430 uses. The dampers, springs, swaybars, and hubs are obviously upgraded are upgraded, but surprisingly, it uses factory control arms that have been upgraded with spherical bushings.

You should see a pattern developing here. All of these cars really are just tuned production cars and they all retain the factory engine and suspension configurations, along with production chassis.

Now, the BMW M3 GTR is a pile of shit in my opinion. It's an awesome car but it is wrong for the series in every way. This car is built by BMW. The old E46 M3 GTR was built from a body in white chassis as well, but it was an actual production chassis with a roll cage when they were finished with it. This new version starts with a production chassis but they cut the strut towers out and integrated the rollcage to pickup the top of the damper. They cut out the rear wheel wells and welded in an entirely new section. They removed the rear quarter panels (which are not removable from factory) and replaced them with composite pieces (meanwhile the unibody Porsches just add on widebody pieces but still keep the original, albeit clearanced, rear quarter panels underneath). They removed the entire roof section and the top lateral piece of the windshield frame and replaced it with rollcage and carbon fiber panels. The transmission is in the back, which required some additional clearancing of the frame. Lastly, they completely scrapped the factory subframes and they welded in some pickup points on the frame whereby they added in a double wishbone setup in the front and back. It's bullshit of the highest order.

Another such travesty is Cadillac CTS Vs that were raced in the Speed WC series. These cars are similar to what you were speculating on. They didn't take production chassis and then build racecars out of them. GM litterally modified the chassis as they were building them. It would be like if the rules said that you have to build pinewood derby cars out of a wooden block and they genetically engineered the wood before it ever became a block of wood in the first place. They ended up with a unibody chassis that was made using production means, but they made a new chassis altogether. The whole unibody sat about four inches shorter from the floorpans up and the transmission tunnel, firewall, and pillars were all completely different.

I think that with the exception of the BMW M3 GTR, you can legitimately say that the GT2 cars are race cars that are made out of production cars. In my opinion, that is a far cry from the so-called "production based" racecars such as the tubeframe RX8's running in Grand Am, anything running in the DTM series, the current crop of hillclimb and rally Ford Fiestas which have had their chassis cut up and reassembled in order to accommodate an AWD drive train, or the Davis Mustangs in the SWC series that have had their chassis hacked up, firewall relocated, and freaking inboard suspension added in the rear.

rockville

But what about the 911 GT2 RSR? That's the racing version of the 911 GT2.

Swift GT

[QUOTE=rockville,Apr 24 2010, 10:13 PM] But what about the 911 GT2 RSR?

rockville

Running joke...

Mr.E.G.

Well, the GT2 RSR is not a racing variant. Rather it stands for "Really Shitty Radio" and is just the GT2 that is not optioned out.

07gpwS2K

I kinda see where you're going with that logic, but a 40 second gap is HUGE on race track. Now if the GTR was 4 seconds behind the Ferrari that'd be impressive.

Back on topic! Sick video, skilled driver! That being said, the masses are correct: If you're going to write an article or post a blog on a car lapping the 'Ring with a blistering time, it generally has to be a production to really get people excited.

waltk88

I'd guess that a Porsche GT3 RSR would beat this Ferrari around most tracks.

Mr.E.G.

I wouldn't be surprised either way.

There is a lot to be said about real race cars vs. tuner specials and even manufacturer specials.

A few years back at one of the American time attack events, the GMG Porsches that race in the Speed WC series showed up and laid the smack down on a bunch of tuner cars that had considerably more power and no limitations. The GMG car ran in dialed back race spec that they had to run WC races in.

Now, that comparison is not entirely analogous because we are talking about a real race team vs. tuner shops, but you the idea pretty quickly that a ton of power is not what wins a road race. If I recall correctly, the Porsches in WC back then were making somewhere in the 400hp range while some of the other cars in the series were like 600+ hp Skylines and the like.

Also, they ran the Ferrari FXX (800+ hp super Enzo) on the Top Gear track and it was incredibly fast. They also ran the Aston Martin DBR9 Lemans GT1 car and it was 2 full seconds faster in spite of the fact that it is a heavier car with 200 less hp.

The point is that there is a lot to be said for the performance of a proper racecar, but I wouldn't be surprised if the 911GT3 RSR, as badass as it is, to be bested by a car that has considerably more power and no real regulations governing what can and cannot be done to it. I also wouldn't be surprised if the 911 GT3 RSR beat the Ferrari in this case. Once you reach that type of a performance envelope, it's hard to use the conventional wisdom of bench racing to decide who will win.

rockville

Certainly the tires and brakes and the like will make a huge difference. Top Gear compared a Formula Ford (Euro spec) to a Ford GT. The two had similar power to weight ratios but on the track it wasn't close. The FF simply could out corner the Ford GT without effort. But that competition was on a very tight infield track. If you were looking at something like the Ring the results might be different. In my example the FF tops out at a modest 140mph (depending on gearing). The GT of course is around 200. There are likely quite a few sections of the Ring where the FF would sit at redline.[media]http://www.youtube.com/watch?v=g7-S0EDK22g [/media]

Mr.E.G.

That looks like a ton of fun. I see a FF in my future.