usually
Golden colored springs are the weakest, they engage at low rpm.
Black colored springs or medium, they take a little more rpm to engage.
Shiny metal colored silver springs are the strongest, takes a high rpm for them to engage.
You can also use different springs per each shoe.
Example a silver, a black, and a gold
What this does is provide traction on dusty low traction surfaces, as only one clutch shoe will engage, then the 2nd shoe will engage and finally the 3rd shoe. This helps keeps the tires from losing traction and all 3 shoes will engage at different time until all 3 are engaged.
Also, there are two ways to mount the shoes,
Trailing shoes, standard set up sit opposed of the direction the flywheel rotates and this is the standard set up.
And
Leading shoes the shoes sit the direction the flywheel spins, this engages harder and used on high traction surfaces.
Quote from RC/Driver
Clutch shoe orientation. Technically there is no real wrong direction to put your clutch shoes on. However, orientation of the shoes does make a difference as to how the clutch reacts. The most common setup is called “trailing shoes.” This setup has the clutch shoes aligned opposite to direction the crankshaft turns. This provides a smooth engaging clutch and is ideal for most tracks. When the shoes are turned the same direction as the crank is turning, it is known as “leading shoes.” The leading shoes setup causes the clutch to engage with more of a punch, and is used mostly for extremely high traction conditions.