rockitman

That's interesting. I can see how that would work as long as the computer isn't too smart and realizes the air is too clean on the post cat sensors...

vegasgolf98

Yargk - You misunderstood about the grill vents - not weight- reduced airflow. Have you ever seen a NASCAR race where they put one little piece of tape on the grill or take some off? - That maybe all that is needed to adjust the front downforce.

Sorry, You are wrong about the tire wear - this is a well-know fact and is in almost every race tuning book - if you don't believe me just conduct test like most racing teams. Look at Ny-NJ's results. 1-2* more should be all we need for the GT3.

Z06

With the Corvette.....the cat..o2 sensors work with a voltage related to heat created by the cat, when exhaust temps rise the cat gets hotter and the o2 sensor will send a signal via voltage letting the computer know that the cat is working. No cat wrong voltage and the computer will eventually realize that the cat is not working and set a code.

They had o2 simulators that would send a constant voltage that would indicate that the cat is working, even with this eventually the computer will see no change in temperature and it will set a code.

macfly

So isn't there a way to tell the computer that no code is needed anymore because the cat has been taken out of the loop?

Yargk

I'm not saying extra wear doesn't occur, I'm just saying that it must be less compared to the extra wear in a real race car.

There are 3 reasons why it is much more important in a race car than in a street car. (let's specifically compare the ALMS cars with our street cars.)

1. The ALMS cars run race tires that don't last as long as our street tires anyway.

2. The downforce that the RS wing produces is much less than the ALMS wing. At zero incidence at 125 mph the RS wing produces 11 pounds of downforce. Maybe at larger angles it makes 50 pounds. I'm sure the ALMS cars have over a hundred pounds of downforce on the rear.

3. The ALMS cars weigh less, why does this matter do you ask? Well the increased wear from downforce will be due to increased pressure on the tires. If the car weighs less then every pound of downforce that you add will change the wear by a greater amount from the wear without any downforce. So let's do a simple calculation.

1800 pounds on the rear of a street GT3 with 11 pounds of rear downforce (RS wing at zero incidence) means that the pressure on the rear tires is increased by .6%

1800 pounds on the rear of a street GT3 with 50 pounds of rear downforce (upper extreme for RS wing) means that the pressure on the rear tires is increased by 2.7%

1600 pounds on the rear of an ALMS GT3 with 150 pounds of rear downforce means that the pressure on the rear tires increased by 9.375%

So we see that the difference in wear on a race car is much greater than on a street car, in addition if you reduce the weight on the rear by a few pounds you can cancel any extra wear due to downforce. This would only take a set of lightweight wheels and a carbon decklid and wing.