Landracing Forum
Tech Information => Technical Discussion => Topic started by: maguromic on October 30, 2007, 01:42:00 AM
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Since traction control is legal now, I wonder if you use it if you still need to carry lots of weight for the higher speeds. After all there are several systems available that can do the job with in a thousand of a second that have been proven on some of the most demanding tracks in the world.
It’s my opinion that you would not have to carry as much weight. I like to hear what others think.
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Talk to Ron Main about TC. If the TC gives up the ECU may think that the rear tires are going 250 and the front tires are at 0. Take some lead out to compensate and you have EGTs in the 1700 deg. range., or something like that.
Not a fan,
DW
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Here is the problem, It's not traction control. It's wheelspin control. The available traction is dependant on the vehicle configuration and racing surface. You can't use electronics to manufacture something that isn't there.
Jim in Palmdale
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Here is the problem, It's not traction control. It's wheelspin control. The available traction is dependant on the vehicle configuration and racing surface. You can't use electronics to manufacture something that isn't there.
Jim in Palmdale
Exactly (http://www.cybergifs.com/faces/bigtup.gif),
Sum
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My understanding:Adding weight is to increase traction at speed,to offset lift.
Less weight,at speed,would produce less traction.
Electronic "traction control" reacts to differences in wheel speed.
I'd look at mounting a bar graph on the dash,or colored lights,
that would display the difference in wheel speed,front vs rear.
Then figure out what allowable percentage to program into the
Traction Control.You might decide to can tolerate 10%(for example).
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Since traction control is legal now, I wonder if you use it if you still need to carry lots of weight for the higher speeds. After all there are several systems available that can do the job with in a thousand of a second that have been proven on some of the most demanding tracks in the world.
It’s my opinion that you would not have to carry as much weight. I like to hear what others think.
All vehicles produce lift. Many classes can run only factory aerodynamic aids so if you vehicle weighs 2000 lbs. but has 400 lbs. lift at 200 mph can your traction control hook you up @ 1600 lbs.? Or if you can run a wing can you give up the hp? Some wings take as much as 80 hp to overcome the drag without said wing.
I'll say it agian, enjoy your traction control... oh ya, don't use retarded timing to control engine power.
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Talk to Ron Main about TC. If the TC gives up the ECU may think that the rear tires are going 250 and the front tires are at 0. Take some lead out to compensate and you have EGTs in the 1700 deg. range., or something like that.
Not a fan,
DW
I think traction control is a great thing personally. Ron Main's malfunction is an example of how it should NOT be programmed. The front speed sensor broke, thus giving the ecu a 0 wheel speed in front and like Dan stated 250 something in rear. It would have worked beautifully if it was programmed different.
First, they took all the timing out to compensate for the difference in wheel speed. This is the problem. It took all the timing out and caused some extremly high exhaust temps, literally baking off header wrap. This in the end (my assumption) caused weakened valves and on next run they broke valves.
If this was programmed different they would not have had this problem and motor would have lived the rest of the week.
A better solution would have been to start killing injectors, no fire, no heat and you would have ended up with an aborted run instead of a motor failure.
The technology is there to do it, and make it workable.
Jon
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A better solution would have been to start killing injectors, no fire, no heat and you would have ended up with an aborted run instead of a motor failure.
The technology is there to do it, and make it workable.
Jon
Ahhh...... what a good idea. :-D
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What about the fully programable ignition boxes? Like teh MSD and others that were originally made for boat drag racing. They control the maximum rate of acceleration. That was the box that was banned from a lot of racing as it could be used as traction control. Put a maximum rate of accelration in for each gear and presto, no spin up. If it does spin up it acts like a rev limiter and pulls spark progressively.
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Traction control is a general term describing a devise that is used to control wheel spin or coefficient of friction of the drive tires to track surface…. kinda like “Kleenex” is to describe a paper snot rag…there are many ways to achieve it and one of the simplest is pulling timing out….. this method will give the least amount of power reduction and as in Mains case can cause damage….. There are many ways to achieve it, as John mentioned, you can kill injectors on a fuel injected motor… again not my favorite and a no no on a shared style of intake plenums… fly by wire systems can close one if not all throttle bodies to reduce power… my favorite is controlling the blow off valve on a turbo application, knocks off a lot of power fast without affecting turbo spool up. There are also many ways to detect or sense wheel spin… front to rear wheel is the most common but I prefer clutch inner basket to rear wheel cuz you can also kill power if you are over powering the clutch…. I got all that fancy data crap on my liner to anal ize… wish it woulda told me a rod bolt was about to break…..
Kent
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"Put a maximum rate of accelration in for each gear and presto, no spin up"
Viola!! no acceleration - a little known fact is that in order to set a record you must et to the 2.25 clock.
DW
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I was thinking along what Jon was mentioning. Like Kent says, traction control is a generic word like “Kleenex”. I was looking a the system by Bosch that takes the wheel speed, crank speed and ground speed and does the calculations to do the traction control. With all three it helps eliminate errors. In its simplest form would be to pull timing
I am not trying to get into if traction control is good or bad, but just trying to see if properly deployed if some weight can be left off, for example from 3000lbs to 2500lbs.
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Here is the problem, It's not traction control. It's wheelspin control. The available traction is dependant on the vehicle configuration and racing surface. You can't use electronics to manufacture something that isn't there.
Jim in Palmdale
BUT . . . A traction loss due to a bad surface can be minimized by catching it quickly, and electronics can do it faster. It'd be no substitute for good suspension design, and appropriate driving wheel weight, but worth something. "Put a maximum rate of accelration in for each gear and presto, no spin up"
Viola!! no acceleration - a little known fact is that in order to set a record you must et to the 2.25 clock.
You would here set the maximum rate of acceleration at something well above what the vehicle is capable of. It might be useful to have a different value for each gear.
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Come on guys, do you really want to put all of your acceleration data into a computer and then just put the pedal to the floor and let the computer figure the rest out???
I can see some limited traction control capabilities to help in not blistering a tire by wild tire spin, but I still want to drive the car. The record is part of the equation if you are lucky enough to get one, but they can't take driving the car down the salt away from you and I think that puts the biggest grin on your face :-D.
Remember it is traction control not traction addition,
Sum
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Kent....any chance you had some rods/bolts from falicon, I know
they do some nice stuff...just wondering...
your liner is great...it has some new and old technology working together...
tc is like anything else.....its great when it works.....
Sum, do you really want your ECU to compilate data to trim timing/fuel/boost/air fuel
rpm etc electronically and take out all the pride in mastering the right tune up
with manual controls...?....:):)
Joe :)
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..................Sum, do you really want your ECU to compilate data to trim timing/fuel/boost/air fuel
rpm etc electronically and take out all the pride in mastering the right tune up
with manual controls...?....:):)
Joe :)
I guess I'm confused by what you are saying, but I'm running EFI so there will be a computer that will control the injectors and spark. Will I be running any type of traction control?? No.
Heck I won't be making enough HP to spin the tires anyway, and if I do and it is a big problem I'll revisit this issue and I'll probably end up eating..............
Hey, that was the only good thing about winter in Wyoming. I could spin the tires no matter how little HP I had and it was fun.
c ya,
Sum
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Our bikes have traction control -- manual traction control, that is. Front and rear wheel speed sensors feed into the MoTeC (allowing for different wheel circumferences) and when the difference exceeds a certain preset percentage -- a dashboard light labelled "Warning" comes on. The rider then can do whatever he wants to to do turn off that light.
Traction control takes power out, right? Hey, to go faster I want to put power IN.
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The rider then can do whatever he wants to to do turn off that light.
Traction control takes power out, right? Hey, to go faster I want to put power IN.
Do you think your left wrist can put power back IN quicker and more accurately than a computer?
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The rider then can do whatever he wants to to do turn off that light.
Traction control takes power out, right? Hey, to go faster I want to put power IN.
The higher you get in the horsepower curve the less likely you are to come close to doing that. Watch the Hooley videos and see how fast it gets up on the power curve.
Take weight out? That has nothing to do with traction control, but everything to do with traction. You put more weight in to get more traction. Traction control allows you to control the traction that you have available to you.
Do you need traction control? Are you spinning the tires on a regular basis? Duh!
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LEFT wrist? Unh, that part of me is just there to give someplace to the clip the lanyard/tether. You meant RIGHT wrist, hey?
And I yield the point that I could have the computer do some or all of the figuring necessary to decide, and have it take out some timing or some fuel or some throttle. There's plenty of power in the MoTeC to do all that stuff -- but back to Sumner's point -- where's the fun in that? Maybe it'd save me a blistered tire -- maybe I'd hurt a motor.
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Tortoise- I think you mean right wrist. Otherwise I need an extra throttle on the left. Maybe that is one of those old timer speed secrets.
Dwarner- How can putting in a maximum value limit your acceleration as long as that value is slightly greater than what the salt will allow? If available traction lets you accelerate at x meter/sec and you tell the computer to limit accel to 1.1x then you can still accelerate just as fast, you can even have wheel slip. It is just when your wheels really spin up the computer will bring it back in line. It doesn't even matter how much your wheels are slipping as long as it doesn't let the acceleration run wild.
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I am not saying take all the weight out. Of course you need weight, but do you need to carry all the weight that you would of carried if you didn’t have traction control? I think utilized efficiently with a proper engine management system it can be an asset.
Bad traction would come from too much horsepower and bad track. You can’t control the track conditions but you can control how the horsepower is applied.
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This is going to be interesting....
Let me see...slow down to speed up....
Does anyone remember how bad the salt was in '99? I do, I've got in car video, we couldn't have gone any faster... but then again it's your time and money.
I'll let you guys work it out first.
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The rider then can do whatever he wants to to do turn off that light.
Traction control takes power out, right? Hey, to go faster I want to put power IN.
Do you think your left wrist can put power back IN quicker and more accurately than a computer?
Riding the bike backwards with your left hand on the noise control and a sharp eye on the back wheel is just another unexplored possibility that might be better than too much automation. :roll:
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Great idea, Jack- you probably know a bicycle guy set the European (Resident- I guess) record for speed a year or two ago in Nevada riding ON HIS BACK facing BACKWARDS at 79 mph- only two mph off the alltime record.
Sounds like something that should be explored.
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Riding the bike backwards with your left hand on the noise control and a sharp eye on the back wheel is just another unexplored possibility that might be better than too much automation. :roll:
Yeah, that's what I meant. Thanks, Jack; people mighta thought I'm an idiot if you hadn't explained it.
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Great idea, Jack- you probably know a bicycle guy set the European (Resident- I guess) record for speed a year or two ago in Nevada riding ON HIS BACK facing BACKWARDS at 79 mph- only two mph off the alltime record.
Sounds like something that should be explored.
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I'm thinkin' Jack paid real close attention to Floyd Clymer back in the day.....
Ed Purinton
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Fallin' on the floor over RidgeRunner's last comment.
I didn't think there was anyone on EARTH left who remembers Floyd Clymer and his publications!
Jack's mentor finally divulged!
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"Dwarner- How can putting in a maximum value limit your acceleration as long as that value is slightly greater than what the salt will allow?"
Ask the man who has taken horsepower out and gone faster. What is that Jack says about theoretical race cars setting theoretical records?
Put something on the race track,
DW
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It is not nice to try an fool Mother Nature.
She always wins. :-D :-D :-D :-D :-D
Tom G.
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Don't confuse wheelspin with horsepower. Build a car with solid suspension or put to heavy springs on a car with supension put 70 lbs. of air in the tires,set the 4link or latter bars so the instant center is in the wrong place and you can spin the tires to your hearts desire. 0f course you could add 4000 lbs. of lead.
Msd has an ignition that enables you to set how fast the engine accelerates. Mustang racers at the drags on 10.5 inch slicks have exceeded 200 mph with that system, but not before.
Wheelspin definitely causes oversteer and possible spin, but lack of downforce at speeds over 160 mph is
another problem, spoilers,wings,& weight are required.
To answer the post, probably? We have run 288 mph with a 279 exit speed in our Camero, the car weighs 4680 lbs with 3000 lbs. on the rear tires & 10 inch spoiler. The car handles great at that speed with no wheel
spin after shifting out of low gear. It is possibly too glued in but no weight will be removed at this time. I HAVE NO DESIRE TO SPIN THE TIRES, or get too light.
If the record was close and slower speed ?
jl222
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To answer the post, probably? We have run 288 mph with a 279 exit speed in our Camero, the car weighs 4680 lbs with 3000 lbs. on the rear tires & 10 inch spoiler. The car handles great at that speed with no wheel
spin after shifting out of low gear. It is possibly too glued in but no weight will be removed at this time. I HAVE NO DESIRE TO SPIN THE TIRES, or get too light.
If the record was close and slower speed ?
jl222
Good post, which Camaro are you running??
Sum
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Sumner,
This one:
Getting ready for Bonneville(rebuild)
DW
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Sumner, I think jl222 is John Langlo and you know which camaro that is. Cya (I am not sure this is true, just my idea.)
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In drag racing people take power out and go faster all the time. If you have to much power for the track it make you spend to much time focusing on keeping the car straight. Of course that is drag racing on asphalt which is different. That is why I asked.
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Dan, you beat me to it, but that confirms what I thought was true. Cya in impound, I said that last spring, but didn't deliver.
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Dan, you beat me to it, but that confirms what I thought was true. Cya in impound, I said that last spring, but didn't deliver.
Thanks guys, I guess I should of put my brain in gear and thought for a minute (http://www.cybergifs.com/faces/cry2.gif),
Sum
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You must be breathing too much of that Utah, high altitude air. Or else spending way too much time working on the lakester. Cya
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I think BSR has the MSD traction control ignition boxes on their site.
Basically,you program the maximum acceleration rate for the rpm in high gear.
Works fine on short tracks.
The acceleration rate at Bonneville would be pretty low in high gear.
Don't know if there is a minimum acceleration rate in the programing.
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To answer the post, probably? We have run 288 mph with a 279 exit speed in our Camero, the car weighs 4680 lbs with 3000 lbs. on the rear tires & 10 inch spoiler. The car handles great at that speed with no wheel
spin after shifting out of low gear. It is possibly too glued in but no weight will be removed at this time. I HAVE NO DESIRE TO SPIN THE TIRES, or get too light.
If the record was close and slower speed ?
jl222
Good post, which Camaro are you running??
Sum
Summner????
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Don't confuse wheelspin with horsepower. Build a car with solid suspension or put to heavy springs on a car with supension put 70 lbs. of air in the tires,set the 4link or latter bars so the instant center is in the wrong place and you can spin the tires to your hearts desire. 0f course you could add 4000 lbs. of lead.
Msd has an ignition that enables you to set how fast the engine accelerates. Mustang racers at the drags on 10.5 inch slicks have exceeded 200 mph with that system, but not before.
Wheelspin definitely causes oversteer and possible spin, but lack of downforce at speeds over 160 mph is
another problem, spoilers,wings,& weight are required.
To answer the post, probably? We have run 288 mph with a 279 exit speed in our Camero, the car weighs 4680 lbs with 3000 lbs. on the rear tires & 10 inch spoiler. The car handles great at that speed with no wheel
spin after shifting out of low gear. It is possibly too glued in but no weight will be removed at this time. I HAVE NO DESIRE TO SPIN THE TIRES, or get too light.
If the record was close and slower speed ?
jl222
Bviller, I am not a disbeliever, but are you sure about your weight bias. If my abaccus hasn't failed me, you are running 65% on the rear wheels. Now while that may be great for traction, I wonder what steers the car? Hope you guys do well at El Mirage..........................
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Hi Bob
We weighed the car at a certified trucking scale. I also bought one of those light weight ton & a half floor jacks,thinking it would lift the rear without water in the intercooler, or engine tanks, but it didnt even budge it. Got my money back.
We have 20 degrees caster in the suspension and run the car with a slight rake. I also believe we get a lot of downforce from header exhaust.
At 35-65% weight bias it does handle great and goes straight and no lightness after pulling both chutes by
mistake once.
65% has got to be less than Fred Dannefelzer's lakester, and he has a big wing on it. Hey Freddy i know you're reading this. well?
I looked in my formula I book to verify that they ran 40-60% to 35-65% they had wings to and cornerd like hell.
Thanks JL222
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For easy weighing of vehicles, you might consider getting what we use around Star Industries for weighing bulky stuff: A pallet jack (you know, the thing you use around the warehouse) with digital scale built in. It's accurate to a half-pound (assuming you calibrate it with a known weight), and is rated to 5,000#. The forks are spread just about right to fit front and back of a tire, then pump a few pumps to lift that tire and Viola, you're got an accurate weight reading for that corner of the vehicle. This is how I know my pcikup weight as close as I do -- it's easy to weigh stuff.
The pallet jack with scale will set you back darn near a kilobuck -- but if you've got a need for a pallet jack anyway, it's a fine "option".