I wanted to get a level on my car and i measured the fender from ground up in the back and the front and they are a 3" difference. I was going to get a 2.5" spacer in the front but ive seen that people get a 1.5" spacer and it will give you 3" of lift which doesnt make sense. wouldnt i need to get a 3" spacer to lift it 3"?

 

I just installed a 2.5" spacer lift on the front of my Tacoma. It gave me more than 2.5" of lift.

The strut mounts just a little more than mid way from the pivot point of the lower control arm to the point at which the wheel attaches.

Just like a lever, if you move the middle of it down two inches, the end of it moves down four inches. It's not exactly mid way (I don't think) but that's the general idea.

Yes, the 1.5" spacer will give you more that amount of lift. I hope this helps.