In a perfect world, a race car would always hook anywhere.
It would go down the track straight, it wouldn’t rattle the tires, and it wouldn’t lose traction somewhere down the race track. Trouble is, it’s not a perfect world. We’re dealing with a mechanical beast that is operated under all sorts of different track and ambient conditions. Stuff wears out. Track conditions change during the day and so do weather conditions.
Quite often, a problem with hook develops.
So how do you deal with it?
There are a lot of factors involved when it comes to tuning a car and actually sorting out the race track. Sometimes those factors can prove overwhelming – even baffling. And with drag racing, there isn’t a lot of time to make adjustments.
Thankfully, our pal Jerry Bickel (Jerry Bickel Race Cars) has helped us provide you with a great starting point when it comes to troubleshooting traction issues. Jerry came up with this guide, and it’s a perfect place to begin.
In fact, you might want to make a copy and paste it on your trailer door!
Here we go:
Jerry Bickel Race Cars Troubleshooting Guide
Possible Causes | Solutions |
---|---|
Issue: Tire Shake | |
Clutch engagement too violent | Adjust clutch tension weight, finger height; different clutch setup |
Poor shock settings | Stiffen shock adjustments; replace worn shocks |
Tire PSI too low or high | Adjust tire inflation |
Instant Center too high or low; no tire spin | Raise IC or shorten as required |
Instant Center location moving | Add rear stabilizer bar |
Wrong weight distribution | Adjust weight distribution |
Tire shake (automatic car) | Lower launch rpm; increase tire pressure |
Issue: Crooked Launch | |
Tire PSI unequal | Adjust tire PSI evenly |
Tire rollout greater than 1/2" | Purchase matched tires |
Wheelie bar stagger incorrect | Adjust wheelie bar stagger |
Pre-load incorrect | Adjust chassis pre-load |
Issue: Straight Launch but Crooked Out of Water Box | |
Rear tires have unequal load | Adjust corner weights (spring heights) |
Incorrect chassis pre-load | Adjust chassis pre-load |
Issue: Narrow Tire Tracks | |
Tire Spin | Improve traction; soften clutch adjustment; change launch RPM |
Issue: Choppy Tire Tracks | |
Tires wadding up | Adjust tire PSI, lengthen/raise IC |
Issue: Skipping Tire Tracks | |
Tire shake | See "tire shake" above |
Issue: Straight Launch, CG, Poor Starting Line Traction | |
Wheelie bars unloading tires | Adjust wheel bar height; lower and/or move CG forward |
Poor tire adhesion to track | Adjust tire PSI, change to different tire size and/or compound |
Excessive power application | Adjust clutch, reduce flywheel weight, adjust launch RPM |
Issue: Poor Traction at Speed or At Gear Changes | |
Insufficient weight on rear tires | Increase rear weight bias, add more wing angle |
Excessive torque application | Soften clutch adjustment, revise transmission ratios |
Issue: Excessive Tire Squat (Sidewalls Wadding) | |
Tire pressure too low | Increase tire PSI |
Chassis planting tires too violently | Adjust IC longer/higher, stiffen rear shocks rebound setting |
Issue: Excessive Chassis IC Too Low (Squat) | |
IC too low | Raise IC |
Issue: Down Track Push/Pull; One Direction | |
Tires different size | Equalize inflation; check rollout |
Rear-end not square in chassis | Square rear-end |
Pre-load incorrect | Adjust 4-link pre-load |
Front caster staggered | Adjust caster |
Dragging brake or tire | Check for brake drag; body or chassis contact with tire |
Issue: Wanders/Directionally Unstable | |
Insufficient caster | Adjust caster |
Too much toe-out | Adjust toe |
Excessive bump steer | Check and correct bump steer |
Issue: Poor Reaction Time | |
Front tires too soft | Increase front tire PSI |
Slow chassis reaction | Loosen rear shock rebound setting, shorten/lower IC |
Clutch air gap too large | Adjust clutch air gap |
Clutch engagement too soft | Adjust clutch |
Issue: Chassis Loses Settings | |
Components loose or worn | Check chassis and all components; repair and replace as necessary |
Issue: Severe Vibration | |
Tires out of balance | Balance tires |
Tires shaking | See "tire shake" above |
U-joint misalignment | Adjust pinion angle' check driveline adjustment |
[…] In a perfect world, a race car would always hook anywhere. It would go down the track straight, it wouldn’t rattle the tires, and it wouldn’t lose traction somewhere down […] Read full article at http://www.onallcylinders.com […]
My ranger drag truck hops out of the hole. Not wheel hop. Like it skips one time and goes. Ladder bar coil overs. No anti sway bar. 14 x 32 Hoosiers. Single adjustable shocks w/85 lb springs. Truck weighs 2650 lbs. Run 5.50 in eighth.
Thanks! This is of great help!
I have 5 speed Pro Stock car that I use for engine testing and development. We have been experiencing tire bounce down track 3rd and 4th gear mostly. It appears to be a tire wadding issue that starts on the gear change, we have taken all the clutch out of the car we can bare. The car has never had a off line issues 60ft is an average of 1 second, can a to soft of a tire sidewall cause the bounce down track? During 3rd and 4th it can bounce up to 8-9 times during the run making the car very unstable. The car has electric/air adjustable shocks and the tires have only 5 hits on them. I first hit on the new tires there was no bounce, shortly after we are experiencing it. We have move the IC longer, shorter, lower and higher. we can make the car to anything we want with adjustments expect get ride of the bounce. this is an EFI 498 that we shift at 10,200 and leave at 7,000. Our best guess is the 18705 Hoozers although very similar to the D2433 Goodyear could be the issue, the season is over for the moment a set of D2433 have been ordered. Any help is appreciated!
Having same issue 800+ hp pickup 28 10.50 15 Hoosier bouncing traction lol