BURNOUT

[TYSON14]

When i am in the water box the car wont run straight. So we put a little preload on one side and nothing happen. But what i dont understand is that it will run straight down the track. We put a string on the suspension and every thing seems to be right. So what next?

[kwkracing]

one tire is probably bigger than the other. take a cloth tape measure and measure the circumference of the tire or what would be the roll out.... Some times you have to buy several tires to get the same height!

[FullTimeRacing]

turn in to the burnout ,not like drifting.

[bjuice]

get it up on the tires QUICK once out of the water and you will most likley eliminate this problem...most of the cars i see doing what your speaking of is not getting the tires good and wet and then getting them turning...

[kwkracing]

uneven tires get worse when the grow!!!!

[slowmotion]

My brother says that a car that goes sideways on the burnout doesn't have enough wheel speed.

[dparker]

You would have to be way off on tire size and suspenion to cause this. Your probably coming up on your rpm to slowly. Roll thru the water to the edge of the water box and strike your tires hard. They should almost jump up and start spinning, making sure your in high gear as quick as possible. Your car should track straight then.
One way to do a quick check on your preload is to jack the rear end up and check if the drivers side is coming up first. It should come up about 3/4 of an inch before the passenger side without you in it. Just a quick way to make sure your in the ballpark.
good luck

[Tod74]

Mine used to do that...finally figured out I was not all the way out of the water. :oops: make sure you pull all the way up out of the water before you start your burnout and get it into high gear asap.

[us7race]

Here is a tach video of a pass I made a few weeks ago...
Notice how I hit the gas for the burnout.. I don't have these issues.
This is a 6.26 1/8th Pass...

http://s133.photobucket.com/albums/q68/us7race/?action=view&current=TachVideo.flv

[JEFF69Z28]

SOMETIMES IF YOU HAVE A LIMITED SLIP REAR END ONE TIRE SPINS SLOWER THAN THE OTHER AND COULD CAUSE FISH TAILING,THAT IS WHAT I WAS TOLD.

[radicalz]

When i am in the water box the car wont run straight. So we put a little preload on one side and nothing happen. But what i dont understand is that it will run straight down the track. We put a string on the suspension and every thing seems to be right. So what next?


...sounds like you're not in the box right like 1 tire is behind and 1 in the water have somebody put you in with both rear tires in... :wink: :wink:

[silverranger]

if you have had any welding done on the rear,check the width at the front and rear of the tires to make sure the axle tubes are not wharped. a buddy of mine had the same problem.it would take an elephant to hold it straight in the water. the axles would go in fine,but the right tube was bent in bad. steering the car sideways.it also was scrubbing the rubber off of the right slick....just something to check.

[kwkracing]

Axles do warp pretty easy! You wouldnt think so , but a small weld will pull the tubes no problem! All welding and cutting needs to be done before the housing ends are put on!

[Tod74]

When i am in the water box the car wont run straight. So we put a little preload on one side and nothing happen. But what i dont understand is that it will run straight down the track. We put a string on the suspension and every thing seems to be right. So what next?


If it goes straight down track why would you change the chassis?

[dparker]

When i am in the water box the car wont run straight. So we put a little preload on one side and nothing happen. But what i dont understand is that it will run straight down the track. We put a string on the suspension and every thing seems to be right. So what next?


If it goes straight down track why would you change the chassis?


How a chassis car does a burnout can show you that something is not right on chassis setting. When your going down the track your not spinning your tires so you can keep your car in the groove.
We had a car this year, running a 632, whose rear tires would jump to the left whenever the driver hit the gas in the water box. He would turn into it, leaving the ass end of the car hung out and smoke the tires across the starting line. This car made numerous passes running 8.40s with no apparant problems. A few of the racers told him that something was off in his chassis to do this. He came to the track for another race and decided to try his throttlestop. When the thottle stop came back on it blew the tires loose and the car jumped to the left just like it always does in the water, only this time he was at half track. The car shot from the left lane to the right guard rail totaling his 80,000 dollar racecar.
I think there's alot of cars that have a pretty good chassis that are not set right that still go down the track. Big tires and a well built chassis will shadow wrongfully setup chassis. But when the tires are spinning, it magnifies missettings on the chassis.

[kwkracing]

Take the car and put on a alignment rack and let us know what it read!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

[bjuice]

When i am in the water box the car wont run straight. So we put a little preload on one side and nothing happen. But what i dont understand is that it will run straight down the track. We put a string on the suspension and every thing seems to be right. So what next?


If it goes straight down track why would you change the chassis?


How a chassis car does a burnout can show you that something is not right on chassis setting. When your going down the track your not spinning your tires so you can keep your car in the groove.
We had a car this year, running a 632, whose rear tires would jump to the left whenever the driver hit the gas in the water box. He would turn into it, leaving the ass end of the car hung out and smoke the tires across the starting line. This car made numerous passes running 8.40s with no apparant problems. A few of the racers told him that something was off in his chassis to do this. He came to the track for another race and decided to try his throttlestop. When the thottle stop came back on it blew the tires loose and the car jumped to the left just like it always does in the water, only this time he was at half track. The car shot from the left lane to the right guard rail totaling his 80,000 dollar racecar.
I think there's alot of cars that have a pretty good chassis that are not set right that still go down the track. Big tires and a well built chassis will shadow wrongfully setup chassis. But when the tires are spinning, it magnifies missettings on the chassis.


Just curious. How big of a tire does your friend run..reason i ask this is because i agree with you Big tires can be forgiving and even mask a problem in the chassis set up..( one reason i run big tires 8) )

and what was the reasoning behind running the throttle stop with the problems he was having ?..sure fire way to unload a good working chassis on Big hp engines

Just curious.. :?:

[dparker]

He's a rich business man that use to race 15 years ago and what I hear was pretty good racer. Now that he has unlimited funds, he buys a RM 632 and a all round tube chromemolly car. He started asking everybody's opinion and followed what whoever he talked to last had said. Someone told him to put a thottlestop on and it would be safer until he got everthing just right. Only thing is he had never run a TS and didnt know to bring it on just out of the gate and to set it where it would come back on very slowly. He blamed the track saying it wasn't prepped properly. But very few tracks will hold a 1100HP car coming right back on the TS. He took out 50ft of guard rail and 5 telephone poles that were used to support the guard rail. He was uninjured and within 2 weeks had purchased another Jerry Haas car.

[rob41willys]

I agree with BJUICE that more wheel speed during the burnout should cure the problem. Chassis are all different depending on types of suspensions, wheelbase, corner weights and driver sizes you may not always be able to get your weight bias the way you would like it. sounds like you just have more weight on one side. ( probably drivers side ) no big deal. as long as the car leaves straight and goes down the track straight.

[zipper06]

I don't know if this post is worth replying too, he makes one post and 10/15 people reply, DParker seems to know the person, but Tyson has not responded in 2 weeks after asking the question :roll:

Zip.

[dparker]

No Zip I don't know this guy. Its just that I think his problem is seen all over. We take burnouts for granite. IMO more parts are hurt in the water box than any where else. Its a thread that I thought might hit home with quite of few newer racers that might be having some of the same problems and not want say out loud. If you get a chance, to go to the line and watch you'll be surprised at some of the things racers do from the burnout to the line. Kinda scary sometimes. I've seen racers do their burnout in the water and come to the line with water dripping down on and in front of the rear tire. Then complain that the track isnt biting when they almost take out the tree or the other car next to them. Hopefully some of those racers will look at threads like this.
take care zip

[TYSON14]

Went to the track today. i hooked my two step up and a 6000rpm chip. Just held it to the floor got it in second pretty kwick. It did a hole lot better but my line locks wont hold for about 3 sec then they release. I think it is leaking threw.thanks for the help.

[TYSON14]

here is my times 60ft...1.645....330...4.699...1/8...7.297... how does these sound?

[dparker]

Sounds great. Where you racing this time of year.?

[TYSON14]

alabama internatial dragway in steale alabama. There was about 20 cars there but it was great if you are tuning. We moved the timing a little. I want to run the 6.0 class but we are a long way off. Need more motor...

[BillyShope]

Excellent post, dparker!! At my site, I am constantly harping on the importance of equal rear tire loading on launch. Too often, the response is: Hey, I'm going straight down the track, so everything must be all right!

Yeah, you may be going straight down the track, but, with uneven tire loading, you're losing performance AND increasing the accident risk.