el es tu

With the hoopla about the Redbull car tcs I figured Id post this in the autox/rr section...


In our cars its not possible to disable the active handling but keep traction control. Also many of our cars do not come with launch control.

In hp tuners there is a torque management table for rpm vs gear.

Has anyone considered using this table to dial down torque in certain gears? You could turn the tcs and ah off on the console and then just rely on the values in the table to still give you an advantage as far as having some traction control but also set it up so it acts as a crude form of launch control. One could set up tables for various tires and weather conditions as well...

let me know what you think or if any of you all have tried this...

thanks!

mesospeedy

Never thought of that, it might work! But personally, I wouldn't use it. I'm one of the youngest "old school" people I know, I hate driving asists of any kind! I don't even use them on video games, haha! I like it to all be up to the driver. I mean no offense by this, just my insane way of thinking I'm curious however if anyone has used this

6SPEEDZ

The problem is you have to constantly adjust it for track conditions and you don't have enough time to test and really dial it in. But you could fix it some.

RX-Ben

Thought of it...but you really need a "smarter" approach that incorporates wheel speed measurement. Long ago I pestered HP Tuners about hacking into the traction control tables, but they had not done so, and at this point, I doubt they would.

6SPEEDZ

Traction control programming screams of huge liability lawsuits for them

Bill Dearborn

If I forget to turn off traction control I can run for a lot of laps before I realize I forgot to turn it off. It really doesn't activate that much on a track since you aren't banging gears or sliding around or have a super light car with a thousand HP. AH is something else altogether as it can be used to by the driver to do things that normally couldn't be done. Without AH a driver can not apply the brake on a single wheel but they can when they do have it. All of the control is in the driver's hands and feet since the major input is the steering wheel angle and how much slide slip is generated by use of the throttle. A driver has two choices complain about how it messes them up thus turning off the system or learning how to use it to give themselves an advantage by gaining exit speed on the critical turns that lead to long straights.

Bill

el es tu

If I get some time in the next couple of weeks, Im going to see what can be done with 1st gear to establish some level of launch assist.

RX I asked about the same thing a while back (I belived it was chuck cow) and if I remember correctly the issue was how the ah and tcs are controlled separately from the main computer. I think if a vendor sold a dial adjustable unit that installed on the console there would be a decent market for it. Heck even the 2014 vettes offer more driver control...

Bill I knew you were going to respond with that!
Even if youre not intentionally sliding, in comp mode you get no tcs. This could still allow you to dial a little bit in when you need it - like with rain...

brkntrxn

The first racer that replies to this thread with ideas is going to be strip searched at their next event.

el es tu

Just remember if you hear the snap of medical gloves - RUN!

JerryTX

Launch assist on a track car? You know I thought it would be cool to do a standing start in our NASA Blitz race group and be like the CMC guys (CMC in Texas does at least one of their 4 races over the weekend as a standing start). As soon as I installed the 7.25" QM Triple clutch, I retracted my request of the ST Race director and told him to forget I ever mentioned it! LOL!

naschmitz

I would wager that AH is designed to slow the car down and point it in the direction of the steering input, not speed it up and point it in the direction of the steering input.

drivinhard

it already does. the abs and PCM talk to each other, and monitor delivered torque. the PCM calculates this and the ABS monitors it. It can use a combo of throttle reduction (PCM), and brake line pressure (ABS). The system works pretty well on catching wheel spin, but it's slow to release. (pretty safe for a street car on street tires in the wet). You'd want it to be MUCH more aggressive on a track with race tires.

I don't think really high end traction system use throttle control for wheelspin, I think they get into spark/fuel (because it's faster to react) and the sampling rates on them is likely a ton faster than what we have.

Bill Dearborn

Actually, you don't necessarily need tcs when running in comp mode. If the backend starts breaking loose the EBCM will apply a single brake to control the yaw and may also command a torque reduction depending on the change in yaw rate the EBCM is seeing. It will do whatever is possible within the laws of physics to get the car yawing in the direction the driver is pointing the steering wheel.

I only have one example of that from my C5Z. In an autocross I had set up cars were entering a 90 degree left hander at high speed through a series of gates. To get through the turn and make the 200 ft run to the finish line they had to brake hard, start the turn and start rolling onto the throttle. If they hit the throttle too hard they would spin the car. A number did that. However, I had my car in Comp Mode and could brake hard, turn and as I passed the apex go to full throttle. Speeds coming off the turn were probably in the low 20s. With AH the rear wheels were spinning some but not excessively and the front brakes were being alternately applied to keep the rear wheels behind the fronts and keep the car going in the direction I was steering. With the spinning tires and the hammering of one front brake and then the other the car was vibrating violently but went exactly the way I wanted it to go and did it very fast. Fast enough that I got FTD in all events. Everybody kept asking me how I was coming off that turn so hard without spinning.

What do you mean by the main computer? There isn't a main computer. There is an ECM for the drivetrain, an EBCM for the ABS/TC/AH, an ESC for the Ride Control and the BCM which ties those units together with the rest of the modules in the car. BCM is the closest thing you have to a main computer. The car is basically a system of systems similar to the way modern aircraft avionics work. The systems communicate with each other so they can coordinate what they are doing but that is it. EBCM detects rear wheel spin or drag and sends commands through the LAN to the ECM requesting a reduction or increase in torque. The ECM responds and the EBCM determines if the response is sufficient and either requests more action from the ECM and if that doesn't work applies the rear brakes if the rear wheels are spinning. All of that is triggered by the differences in wheel speeds from front to rear and/or between the rear wheels.

If you are trying to use torque management to control torque during launch or coming off from a turn you are missing the key input which is what are the wheels doing? The NASCAR guys who had a simple traction control hooked up to their cars had sensors to tell them what the wheels were doing (I think it was a drive shaft sensor) and then used a module to limit the ignition. I suspect the F1 version is much more sophisticated since there aren't as many technology limitations in F1 Vs NASCAR.

Bill