Rear Suspension

Question 1

In a 4-Link drag car, the starting point for the rear end should be 1/2” to the left of the center line to help launch the car straight.

Answer 1

False/ In a drag car, the rear end should be centered.

Question 2

Which type(s) of lateral locator would you find on a ladder bar drag car? Diagonal link or Wishbone

Answer 2

both

Question 3

In what type of vehicle would you find a jacob’s ladder lateral location device?

Answer 3

Non-wing sprint car

Question 4

Tristan and Randy are discussing 3 link suspension tuning. Tristan says lowering the front mounting point of a pull bar will increase traction on acceleration. Randy says lowering the front mounting point of a pull bar will decrease traction on acceleration. Who is correct?

Answer 4

Tristan only

Question 5

Andy says wrap up occurs during deceleration. Dave says wrap down occurs during acceleration. Who is correct?

Answer 5

Neither Andy or Dave are correct/ Wrap up = acceleration / Wrap down = deceleration

Question 6

Lonnie says that asphalt cars have the panhard bar mounted to the frame rail on the right. Paul says that dirt cars have the panhard bar mounted on the frame rail on the left. Who is correct?

Answer 6

Both Lonnie and Paul are correct

Question 7

Billy says that a Watt’s link lateral locator is used on a road race car because they allow the rear end to move straight up and down.

Answer 7

True

Question 8

What is the proper orientation for a birdcage on a 4 bar dirt modified?

Answer 8

6 o clock & 12 o clock

Question 9

In what type of race car would you find a birdcage being used?

Answer 9

Dirt 4 bar late model

Question 10

What is loose roll steer on a race car?

Answer 10

Rear end pointed towards the outside of the track

Question 11

What is tight roll steer on a race car?

Answer 11

Rear end pointed to the inside of the track

Question 12

Which tire contact patches should be lined up on a dirt car modified?

Answer 12

Left side

Question 13

What component(s) should be used with a drag car using ladder bars with leaf springs?

Answer 13

Axle cages

Question 14

What causes a race car to roll steer?

Answer 14

Angles of the trailing arms as viewed from the side

Unequal length trailing arms

Question 15

On a 4 link drag car, changing the bottom bar angles has no effect on the instant center or the launch of the race car.

Answer 15

False/ Changing the bottom bar angles DO have an effect on the instant center and the launch of the race car.

Question 16

Brandon and Greg are discussing 4 link drag cars in class. Brandon says that instant centers that fall below the neutral line will cause the rear of the car to squat. Greg says that instant centers that are above the neutral line will cause the rear of the car to squat. Who is correct?

Answer 16

Brandon only

Question 17

On a leaf spring car, what devices can be added to improve acceleration traction?

Answer 17

CalTracs
Traction bars
Pinion snubber

Question 18

What angle should an axle damper shock be mounted on a race car?

Answer 18

Uphill toward the front

Question 19

Which drag car rear suspension offers the most tune ability?

Answer 19

4 link

Question 20

Mike and Dave are discussing 3 link suspension tuning. Mike says lowering the front mounting point of a pull bar will loosen the race car on corner entry. Dave says lowering the front mounting point of a pull bar will tighten the race car on corner exit. Who is correct?

Answer 20

Both Mike and Dave are correct

Question 21

Changing the height of the instant center off the race track on a 4 link drag car will have no effect at 60’ line.

Answer 21

False/ Changing the height of the instant center can effect initial launch, 60’ times, and the ability to keep traction down the race track.

Question 22

A J-Bar and panhard bar are two completely different components.

Answer 22

False/ The J-Bar and panhard bar are the same component. The J-bar is shaped like a J for pinion clearance but is still considered a panhard bar.

Question 23

The recommended starting point for the bottom bar on a 4 link drag car is level.

Answer 23

True

Question 24

Changing the height of the panhard bar will affect the pinion angle.

Answer 24

False/ Changing the height of the panhard bar will effect the roll center height.

Question 25

A Watt’s link is preferred to a panhard bar on road race car because the panhard bar moves in an arc causing the rear end to shift back and forth.

Answer 25

True