Why couldn't the C5 be programmed to rev match under certian conditions so that we would not have to heel and toe on the track? It knows the vehicle speed, it knows what gear the lever is in (I think), it knows when the clutch is depressed, it knows when the brake is depressed, and it controls the throttle. It would come on only under the following conditions: 1. Competitive mode engaged, or on it's own control button. 2. brake pressed. 3. Clutch pressed. 4. Gas not pressed. Then when you move the shifter into a gear, it would rev the engine to the required speed for that gear at your current MPH. That's a very simple calculation. The robotic clutch DSG cars already do this, so why couldn't our cars be programmed to do it? It seems to me, all the sensors and controls it would need are already there.

 

It certainly seems feasible, but if you've read a review of cars with DSG, they have lots of issues with jerking/surging at low speeds. IIRC, MT said they felt like a high school kid learning to drive stick when navigating parking lots. And it's a pricey option. Not to mention, some of us prefer the satisfaction of rev matching ourselves, without computer assistance.

 

But this system would only activate when it's turned on by a switch and the brakes are applied. So low speed jerking would not be an issue. I'm sure some would rather rev match themselves, but there are those, like me, that are not yet skilled at it and don't like the idea of rolling their foot partly off the brake when comming down hard from 140mph. And I'm sure you'll agree, the computer would be capable of rev matching so well that the clutch release would be smooth enouph to not upset the chassis at all. Maybe even possible to drop the clutch after entering a corner. As for cost, since no new parts are added, only a program change, it couldn't be that bad.

 

I don't think there is a sensor for what gear you are in, and with the clutch pressed in, it can't calculate by RPM to MPH ratio.

Besides, Heel and toeing is tons of fun. Might as well let the car steer and brake itself too, and watch from the stands

 

Ouch! Yeah, other than heel and toeing, the driver is pretty much piontless. Would you like your ABS deactivated? Wouldn't want the car to help you drive. I know for a fact that automatics know what gear they are in, but they have to since the computer controls that. Our cars do know when you are in first gear because they have skip shift. Does anybody know for sure whether the ECM knows what gear the car is in or not? I would like more opinions. Tell me if you think this is a good or a bad idea. I'll try not to take offense. (of course, I might anyway)

 

Why not? As long as it has a sensor to tell it what gear the lever is in, this is a very simple calculation. What does the clutch have to do with it? Thanks for responding to my post, by the way.

 

Heel-n-toe

 

I know this is out of place on a c5 but in my old jeeps I sometimes needed three feet also . My solution was easy , I used a bicycle brake lever and cable attached to the back side of the throttle pedal assembly and attached it to my shift lever . Not classy on our cars but maybe a twist throttle off of a motorcycle would do the trick . Good luck !

 

Wouldn't be any fun that way.

 

I don't race but I have a thought. I'm sure they are points during this evolution where you want to have different levels on brake presure, clutch engagement/disengagement, and a throttle postion that allows for acceleration or deceleration. So your combination of voluntary postions for all of these are all over the place. How would your computer know WHEN to rev match? Does it do it when the clutch is barely pushed in or when you start to let it out? How hard on the brakes do you have to be? And does it try to match when the brake pedal is going down or coming up?

All of this may happen so fast that my questions are needless but it may also be the reason that the DSG car is so herky-jerky.

 

 

I may be wrong, but wouldn't the new A6 cars (with paddle shifters) behave exactly this way?

 

Why not, the BMW M3's SMG II matches the revs.

 

You mean like this:
http://www.edmunds.com/insideline/do...ticleId=101938

As time goes on, computers and machinery get better and better. The clutch is one of the items that is doomed. Tomorrow you will be completely eliminated from the driving equation. A sport car will no longer be sporting. If you want to race, just push the "Race" button and just set back and relax. No skill required.

Me? I want my clutch.................

 

The only purpose of rev matching is aviod sliding the rear tires and burning the clutch while downshifting. Driving on the street, we never down shift to third gear at say, 70mph, unless we want passing power. So we can use our right foot to hit the gas and rev the engine before releasing the clutch. If we downshift to third at 30mph, it's not a problem because the rpms are close enouph to idle at that speed. On the track, we want to downshift at high speed while in the braking zone so three feet would be nice. Since all you are trying to do is match the engine revs to where they will be once the clutch is released, it does not matter how hard the brakes are pressed or where the pedal is in it's travel. As long as the clutch is depressed so that the system would not activate while in gear, and the brake is depressed so that the system only activates on downshifts and when heel and toeing is required, it should work fine. How many revs you need does not depend on how hard you are braking or where the clutch pedal is, only what speed you are going and what gear you are going to. You racers agree?

 

I like my clutch too! I just don't like smoking my tires and clutch down at the end of the back striaght. Dude, a car that would rev match for you is a long way from driving for you. The problem for me is the only place I can even practice heel and toeing is at the track. I only get to do that every month or so and I'm a little busy at the time. How often do you downshift to 3500rpms while braking on your drive to work?

 

Hey Dude, er.......Paul, aren't there any backroads there in SE AZ that you could practice/learn on? Instead of learning and increasing your skill at it, you seem to be wanting to take the easy way out. Let something else do it for you. Once you learn you won't be "smoking my tires and clutch down at the end of the back striaght[sic]". Practice, son, practice.

 

It is very close, but still jerky unless you lift slighlty to upshift. Downshifting is not a problem.

The BIG challange is most ppl do not know when to properly shift. ppl upshift too soon ( low rpms) and downshift at high rpms.

Upshift at redline, downshift as the car slows into a braking zone.

 

Actually, the roads around here all striaght. The mountian roads have bicycle riders, sheer cliffs, and very slow traffic. But I am not an excuse maker. My next track event I will dedicate to forcing myself to heel and toe. I know how to do it, it's just my normal reaction to put my foot in the center of the brake pedal. Look guys, I'm not a pansy. I'm not trying to avoid learning the skill, I just thought it was something very feasable that could be done not only to the C5, but pretty much any modern fly-by-wire throttle manual tranny car. I have never heard of ANY non-DSG car being able to do it either stock or modified. Even for those that can heel and toe well, the system could make race driving not only easier, but also more acurate. As I siad before, it might be so smooth you could release the clutch in the middle of a corner. There are people selling lots of useless crap for cars. This, nobody is selling and it would actually be functional. I asked why, that's all. At least give me credit for a different type of post. I could have asked what you thought of Khomho tires or if a GTO is faster than a C5.

 

You don't need curves to practice, and you should be in the gear you want before you're into the corner. Anyway, that's how I was taught. Then power out. I'm no Pro (and it shows) , but it works for me, using the brake/throttle through the corners.