View Full Version : Are Radiators and Brake Ducts too good?

31-01-2016, 06:15
For the longest while, I've noticed that you can gain an excessive amount of speed from dropping the radiator and the brake ducts. Now this doesn't mean that doing so is unrealistic in Project CARS, but it tends to affect the drag in a rather strange way compared to what we see in real life speeds.

Let's start with the Aston Martin V12 Vantage GT3. The car has a 38.1mm restrictor I believe and weights 1275KG. In real life however, it is rated at 41.5mm and 1280KG. The car produces somewhere around 520HP on average in Project CARS. In real life, someone ran the V12 at Le Mans achieving a whopping 188MPH down into the first chicane. I even asked the person who posted the video and he confirmed the speeds on the track.


In this video you can see how quick the V12 is down the straight. But what does this have to do with PCARS? What does it have to do with Radiators and Brake Ducts? Well to start, The V12 is capable of 187MPH with the Radiator at full open and the Brake Duct at full open. Now remember it has a smaller restrictor in the game than the real car. We are already 1MPH down from real life. Take the car down to a Radiator of 20 (which you can run long races without a problem on) and a Brake Duct of 0 (since Le Mans gives plenty of time to cool the brakes) and You find yourself hitting 193MPH. Thats blistering quick. This car isnt even capable of this by what the real car can do. We know these guys try their best to get the most speed out of the car without harming the cooling of the motor and the brakes. Hitting 193 just doesnt seem possible. This car is already good as it is. It is uncatchable at Le Mans. I know what some of you are thinking. Maybe this driver wasnt getting everything out of the real car? Well even if he was, he had to be using a larger restrictor. On top of that, he had a pole lap of a 3:59. Thats fairly quick. The PCARS Aston is even faster.

But thats just one car right? Wrong. Lets go to the BMW M3 GT. With the brake ducts all the way open, it is capable of 183MPH. Running the 20 Radiator and 0 Brake Ducts, It is capable of 189MPH. Okay, now something is off. This car is running the real BMW 2011 LM BoP from what it looks. This gives it just above 480HP and 1245KG. In 2011, the factory BMW car went 182MPH. Now the current car in PCARS was updated to have wider tyres, so 183 makes sense because the car would be carrying more speed through the corner onto the straight. But when you lower the Radiator and the Brake Ducts, your doing speeds that this car is completely incapable of. It makes very little sense to me.

Another car was also tested. The V8 Vantage GTE is capable of 178MPH with the Radiator and the Brake Ducts open all the way. The real car did 182MPH in real life. Thats 4MPH short. The V8 Vantage GTE in PCARS has a .4 larger restrictor than the WEC BoP 2015 car, but has the same 1225KG weight restriction. With the brake duct fully closed, the car is capable of 181MPH. This seems perfect. The car is acting as it should speed wise considering its already on the wider tyre in real life that the M3 was given, however if you take the radiator down all the way to 20, it goes 184MPH. This isnt as bad, but it is faster than what seems realistically possible. I will say that the V8 Vantage seems to be the more accurate car with drag reduction from the tuning options.

All these tests where done using low downforce and 45L of Fuel., Slict-Soft Tyres, on the Playstation 4 with a T300RS

Now, lets go to Tracks. Jorg Muller ran the Marc VDS Z4 GT3 at Spa in 2014 at the 24 Hour race. The fastest Qualifying time was from a Z4 with a 2:18. Jorg has a video of him running in the fog on the track.


I took the same date as well as using Fog which Jorg had to deal with and proceeded to test open Radiator and Brake Ducts. My fastest lap with them open and a full tank was a 2:18 flat, already putting me on pole. I then took the Radiator to 30 and the Brake Ducts to 15 and ran a 2:17.1. You can gain nearly a full second just from lowering these options, meaning they are partially responsible for the "faster than real life" lap times.

Now we all know that you will always be faster in a game than real life due to driving exploits and tuning exploits, however from my tests, these two tuning options are responsible for almost a second of those times on most tracks. Much more on a track like Le Mans or Monza. I have no issue running faster than real life, however its not a handling exploit, but a speed exploit. When your going 3-4MPH faster than real life cars are capable of constantly, then something is off. In my opinion, I think that the cars are using their natural drag rations provided by the manufactures when the Radiator and Brake Ducts are fully open. When you close these, they are obtaining a much lower drag ratio than possible. This tends to be very inaccurate.

How do you fix this? Well in my opinion, I feel that the cars natural drag should be at 0 Radiator and around 35 Brake Duct. This means the car would do the same speed at 0 Radiator and 35 Brake Duct as it originally went at 100 Radiator and 100 Brake Duct. We may see much times slow down to something more realistic as well as seeing speeds in the cars that make more sense. After all, these are pro teams capable of reaching these speeds and times. Why are we able to go 5-6MPH faster than possible, even on say a stock setup with low Downforce, Radiator, and Brake Ducts?

What do you think. Should these options be edited to prevent impossible speeds from being achieved? I myself think that the Aston V8 acts very real speed wise at 100 Radiator and 0 Brake Duct doing 181. If they were edited to my suggestion, it would do 181 or so at around 30 Radiator and 0 Brake Duct.

I hope the Devs see this. It is a serious gripe to me after all.