I have heard that installing high performance coil packs will improve performance. Is it a sales pitch or will I feel a difference to justify the cost? And if I do go down that road which pack should i get ?

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2000 X5

1999 Z 3 2.3
1994 Dodge 1500 4x4
1990 Jeep Wrangler
1947 Dodge p/u 4x4 small block