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Just curious, you don't hear all the scuttle buttt anymore about TC, especially the Davis unit.
So guys still using them? Everyone have it why talk went by wayside? Something newer and greater?
Just curious and getting conversation going with my thoughts
it was proven several years back that some times a little wheel spin is faster and needed , i think bloomer done some testing and was faster without it , in some cases i guess it would help , like with a green driver , how ever , it could be a hindrance in learning throttle control ....JMO....
Being that the activity on the tech forum is all but dead, I doubt you will get any useful info on a subject that will incriminate anybody who talks about it. I will say this though, I wish I sold TC units. They could be completely useless and no one would ever know. No one would ever come out and publicly disavow your product for obvious reasons. lol
I do not believe there are any top drivers running a Davis unit. A much more sophisticated unit that could detect yaw, wheel position, and other inputs could in theory, be programmed to work. Something that just limits wheel spin will hinder a good driver in traffic or if the car is off a bit.
There is a reason, years ago you saw so many of the Davis units for sale used. While not 100% useless, they don't provide much gain for the average guy.
Contrary to popular belief, the more throttle control and ability to sense wheel spin you have the more it will help. Meaning a top driver will get more gain then an average one. Those units basically just work of RPM per second gained and when the RPM hits a spike in the climb rate they retard the timing. However the units can only kill about 15% power before they will start to pop and bang, so on a 800HP engine about 120HP is all it can reduce the engines power without being completely obvious. However if you can only sense 40% wheel spin, then you will still push on the gas pedal and keep the wheel spin at 40% (actual wheel speed, remember it only senses spikes or large rates of RPM increases. It is also not really that hard to know who's running it and a trained ear can hear the engine change pitch when it retards the timing 10 to 20 degrees (depending on how it's set).
I could write 20 pages on TC and various ways it's done or hidden and have always been very open about TC as I have tons of years of research on it and was one of the first people to try it clear back in 1994. To save writing a monologue, if you have a question post it and I'll answer it the best I can but some things I may not want to get into. Things like how certain stuff is hidden and what not, that stuff I pass onto tech guys. People often ask why I know so much about it or why do all that work for something illegal? Well, if you don't fully understand this stuff and how it can be done, you will never know if someone is doing it. Having the knowledge to be able to do it, tells you how to find those are doing it and how they are hiding it.
Billet
I always figured for drag racing or asphalt racing especially road course it could be helpful but after that not so much. I hate when it kicks in on my pickup truck even.
Couple years ago at pri guy had unit that works with brakes and GPS. His claim was GPS totally accurate and I laughed. Told him Google GPS can't even locate my house in correct spot.
I'll add some side notes:
1. The amount of wheel spin a Late model operates at is staggering to most people. Your best drivers can't sense wheel spin under 25%, obviously I haven't tested everyone but I haven't found one yet.
2. If you have a balanced car and limit wheel spin (car that has enough power to spin wheels at anytime) to around 12 to 14% the car will get a push on exit. Maximum laps times are always with more then 12% wheel spin. Reducing wheel spin more and loosening the car so it doesn't push slows lap times.
3. Any timing based system, regardless of how accurate it can measure wheel spin is limited on what it can do as far as killing power to control it.
4. Any system that works off a RPM climb rate is extremely limited on what it can do
5. A system that actually measures vehicle speed/front wheel speed vs rear wheel speed is much more accurate and where the larger gains can be had.
6. Most systems out there in years past where very unreliable
7. Are there systems out there now that are reliable and effective? You would be a fool to think no, but I don't think there are all that prevalent and if someone took the time to make one, they would keep it to themselves, IMO.
Jim, it's completely possible for GPS to be accurate enough for a system to work. If a guy really wanted to make one and wasn't afraid to spend the money, I have no doubt it can be done quite easily but the development cost would likely run into the 100K mark pretty easy with prototypes and revisions.Quote:
Originally Posted by Jim11h
However the person you are likely referring to is John Gregory from Racetronics. There are several ways to measure vehicle speed:
1. Wheel senors: Prone to fail and if it does it reads 100% wheel spin and thus will activate the system and shut throttle, apply brakes or whatever and can be very dangerous. I know this from experience and just shutting the throttle mid corner can spin a car out in front of the field (happened to me, lol)
2. Ground speed sensor, no real experience with them but my research has shown they may not be super reliable or accurate.
3. GPS, it doesn't have to be that accurate to be honest to give an average vehicle speed to reference the speed to limit rear tire speed too. However you can always lose signal at some remote tracks so that could be an issue but It's probably the most reliable way to record vehicle speed out there today.
The main issue with GPS isn't the GPS part of it, but getting a good way to control the wheel speed: You either have to control throttle, use brakes, or timing/ignition (most common 3 ways), hiding that part of the system is where it becomes more troublesome and a lot of work to do.
There are systems out there that use a combo pump/actuator to apply the brakes in a self contained small unit to minimize lines and other parts that a system like that needs. But it still falls on needing a way to activate and control either throttle, brakes or ignition.
As far as the Davis stuff: I think Shannon is mostly focused on the No prep and drag racing stuff for the last 10 years or so. I'm not sure he works on the circle track stuff at all anymore, but don't know that for sure.
Wasn't gonna mention business but you nailed it. Nice guy and know someone whom bought his unit. After using couple times he took it off but said it taught him where he was lacking. I'm kinda believer that your butt tells you majority what ya need to know
speaking of drag racing , i saw a article several years ago about a control device that used a sensor on the front wheels and the drive shaft to control wheel spin , i have wandered if this would work on a dirt car using the rt frt wheel , which is always on the ground and the drive shaft , you ever heard of this billet ?
I read a book on performance driving. IT catered to asphalt but still had some good take always.
This particular F1 driver was 1.5 seconds faster per lap WITHOUT traction control on a blind test he didn't even know he was participating in.
Interesting note about the butt. The seat is the the most valued part of the car for safety obviously but it was also the only one of two parts that transfers the feeling of the car to the driver. It's a language interpreter/decoder if you will. A badly designed seat or one that doesn't fit properly made almost the same improvement's as traction control did.
I wish tire prepping were talked about more. I'm pretty libertarian when to comes to that topic. I wish I knew how many drivers are doing it on the local and regional levels where tire testing is nearly non existent or very expensive for a track to do. I'm willing to be a paycheck it's a whole lot more than any one would guess.
While tech'ing should be the tracks job, we all know with the state of racing this financially isn't all that feasible for the tracks. Most of the time it's the racers that police the other racers more then the actual tracks, but if a track had to do a costly tech item every time someone thought someone else was cheating. . . that would get expensive.Quote:
Originally Posted by Lizardracing
However what many won't do is protest or pay to have the test done, if you are that sure someone is cheating then for the small fee that it costs and they if are in fact guilty will come back to you in the following weeks in purse money pretty quickly. While some may hold a grudge when they get protested, I don't as I actually find it quite humorous.
Things like tire doping an easy way and cheap is just have the track use a durometer and check the top 10, if some guys tires seem different then everyone else then the track can note that and suspect something is up and then go farther or decide if another team wants to pay the protest money to have the tires checked. While not perfect, it's a start and doesn't cost anything but a little time to do an initial check with the durometer. Obviously a duro doesn't catch all tire dopes but it's better then nothing.
I was the tech guy for two local tracks. Both UMP at the time. Niether liked my style nor did UMP so that ended and I went back to racing my own car.
I know of matter of personal experiance, several guys in my area doping tires and never once have they been caught. The secret is you don't have to soften the tire to promote grip and reliability and to prevent glazing. You can do it with sipes/grooving but all that R@D takes a toll on the budget as well. Our local tracks are all "Dolly Pardon" style so the guys I race with are on smaller budgets so making a POS tire last more than two nights pays WAY more dividends than does that one or two extra finishing position. A $60 bottle of prep for 4 tires will make the tire last twice as long. I'm pretty sure that's why the tire makers don't want anything to do with it. If most track promoters actually knew the business of what it takes with a small to almost no budget teams and realized that right there is MOST of their clientele they might just change their minds and allow TC in some form or another whether that's tires or electronic devices.
That's how they all work when I say a senor based system or one that actually measures wheel spin. All you need is a vehicle speed, that can be a front wheel sensor or anything that would measure the speed of the car like a ground speed sensor or GPS. Then all you need is something to measure rear wheel speed, that could be anything from just a RPM signal, rear wheel speed, driveshaft speed or anything from the crankshaft to the tire. The last thing is a way to stop wheel spin, IE throttle, brake or timing control.Quote:
Originally Posted by fastford
The issue with sensor based stuff is reliability and hiding it. Using a tach or RPM signal for rear wheel speed is easy to hide but you would need to adjust the computer for every gear change or tire size change. While not hard, your going to have to remove computer from car to adjust the ratio or drive the car and have a way to reset the zero spin %. This can be a red flag, that something is up. Then you still have the vehicle speed sensor/item to hide.
Actual sensor based systems can actually control the wheel spin to a set %, I had one where I can just drive like normal but instead of modulating the throttle off the corner I just hold it to the floor. It would adjust the throttle 7 times a second to keep the wheel spin at the % I set it at. The problem with this was there are sensors on a front wheel and a rear wheel, then a Tee in the power steering to power/move the servo to work the throttle, power steering solenoid, a computer, wires and etc. Back then it wasn't known about thus not illegal so you didn't have to go crazy hiding it as no one knew to look for anything.
Now, could a guy get away with this today? Not real likely, but I feel like if I tried I could probably slip this by most sanctioning bodies but it would be a lot of work. I won't get into a ton a details but someone that's pretty knowledgeable about these types of systems really only has to look for a few items and trace that stuff back. No matter how good you hide something, there are things that have to be there and if you follow that stuff closely on the car and don't assume that firewalls and what not aren't double walled and if a like or wire goes thru something it in fact comes out the outer side with no Tee off it. Given 20 to 30 minutes of time, I feel I could find TC on about any car excluding timing based systems since there isn't any way to check the electronics of that quickly and be accurate.
Hey Billet from your studies, how much tire spin % can there be on a dry slick type track, something cleaned off with some black all around? We were sitting around talking about this in the pits, most guys couldnt comprehend how much tire spin there could be in these conditions.
Open engine LM average slick track (not super super slick):Quote:
Originally Posted by Kromulous
Vehicle speed low 70's MPH
Rear tire speed just over 100 MPH
As an average, on this track average actual vehicle speeds where around 65 to 95 MPH, rear tires where generally going 20 to 30 MPH faster then vehicle was at any point the driver was on the throttle.