years: 81/90 engine: 4.2L (258) diameter: 3.95" - 100mm grooves: 6 years: 87/90 engine: 4.2L (258) diameter: 3.95" - 100mm grooves: 6 years: 81/86 engine: 4.2L (258) diameter: 3.95" - 100mm grooves: ...