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View Full Version : I Know Someone Here Knows: Torque Mapping Question



Jag_Warrior
02-25-03, 02:18 AM
OK guys, so how does this torque dial work? How would it affect the point at which maximum torque is developed, without affecting the horsepower developed? If you dial the torque, to lessen wheel spin coming out of slow corners, wouldn't you also somehow affect the horsepower? Something tells me the answer to that is "no". This has to do with the torque curve/horsepower curve vs rpm graphs I often see, right?

How does it work? Through the ECU? Is it basically a fancy variable timing system?

FLATOUT
02-25-03, 02:48 AM
I would assume it is all done through ECU mapping. An ECU can contain hundreds if not thousands of different throttle maps that can effect how much horsepower and torque is produced and where in the rev range. Due to the new rules this year I assume the fuel mixtures can't be remapped to save gas but I guess the computer folks figured a way to either move the torque curve up or down or to change the characterisitcs of it.

Remember that horsepower and torque are the same things using different calculations. That being said you would think that if you lowered torque you must therefor lower horsepower and subsequently lower fuel consumption but apparently not.

Where are all the computer experts on this board. I would be interested to know as well.

Regards,

Jon

Miljax
02-27-03, 12:44 AM
We were wondering the same thing this weekend... Please,somebody give me some peace of mind!!!

nrc
02-27-03, 01:27 AM
Cosworth's Bruce Wood talked about the torque maps in this story on CART.com (http://www.cart.com/News/Article.asp?ID=5324).


A rotary switch on the steering wheel will allow the drivers to select from five different pre-determined torque maps.

"The maps are all pre-set before the season," Wood pointed out. "We'll give the drivers the power curves showing what each map does and it's entirely up to them and the team to decide which one to choose. The driver can change whenever he wishes.

"I think it's definitely good to have the ability to change the engine performance. If it's a wet race, for example, it will be really useful. I think it's good for the drivers to have that tuneability that allows us to put on a better show."

The idea is that you want to be able to change the power curve to suit the track and conditions. For a slippery track you may not want the power to come on so quickly. You may want to pick a power curve that doesn't make you shift in the middle of a fast sweeper or grab and extra downshift coming out of medium speed corner. It may also depend on the driver's style and the car setup. A car setup for speed on the straights at Road America may use a different torque map than a car setup for higher downforce.