[jamal]

The bolts you should use depends on where you are going to put them.

The front struts mount to the upright with two bolts. The lower stock bolt is 14mm. The Upper bolt has a slightly larger shank- 16mm probably. The OEM crash bolt is just a standard 14mm bolt that goes into the larger hole give you play to add or remove camber. This is a perfectly good solution and is pretty much what I did in slotting the lower holes in my struts to get more camber. Since it is the same size and thread pitch (just a slightly smaller shank), you will get the same clamping load and little change of slippage. Bolted connections are held together by friction and not shear force on the fastener.

The Whiteline, HR, Ingalls, SPC etc bolts are smaller than 14mm and are designed to go into the lower 14mm hole. The way they adjust is with a 14mm cam that fits perfectly into the upright. To take up the space between the shank of the bolt and the hole in the strut is a washer with a small tab. These aftermarket bolts have to be used in the lower 14mm hole. If you tried to put them in the top you would have a gap between the cam and the upright and the bolt/tab and the strut. With a smaller bolt this is a bad thing because you have less clamping load and a gap between everything so they are much more likely to slip. If you do want to use these, put them in the lower hole and set them to max negative camber because this way the load is aligned with the cam and tab so there is no force trying to rotate the bolt and they won't slip. I have them on the rear struts of my car installed this way and they have been trouble free for years.