In this video, you will notice the left front tire lift slightly, then it comes straight back down before the car moves forward..

Anyone have an idea what causes this?

The motor is running flawless with no lag, no bog and no stumble..

http://www.youtube.com/watch?v=h5ldsn0aoh8

Tires unloaded and spun dropping the front back down.

Looked like you may not have enough front end travel. Could be a slick starting line, too much tire pressure, worn slicks, shocks too stiff (front or rear).

Thanks.. I understand now...

Check the rear leaf spring shackle angle, if it is slightly(less than 20 degrees) to the rear at static hieght jack the car up (high enough to let the rear end clear the ground when let down) and put jack stands under the frame so the rear end will hang down and not touch the ground, if the shackles point straight down or to the front you need to move the upper shacle hangar forward so the leafs springs will not go by the center of the upper hangar and pull the rear of car down on the launch making it porpoise or bounce on the hit of the throttle Let us know what you find and do to fix it

tell us about it. you have the old hook spin hook front end does not transfer well.
minimum 50/50 drag shocks better ranchos set at 7 or 8 cal trac 90/10s out front??

second look see you have cal tracks but your front end had next to 0 movement???

Thanks again guys for all the information... The rear shocks and the torsion bars are set up for street driving... In fact, Al_Aguire has scolded me several times for still having air shocks in the rear, but thats something I need to keep the tire from scraping until I get some new wheels with more back spacing..

And Barry, you're right, it did hook, spin and hook again..

On Diego Ted's duster we had similar symtoms so we did what caltracks told us, and that was that we needed 5.5 inches of front end travel. So we cut the upper and lower control arm bump stops and then lowered the car to get the travel we need. If you do this and the car is to low you might have to get taller tires, and make sure you at least get some 90/10 front shocks,because it almost looks like you have front end limiters in the video.

Cab , are you saying : with the rear tires of the ground the bottom of the shackel should be angled to the back of the car. Mine is angled to the front about 6*. This could be my problem with traction.

Sheldon