Spacer lift proportional?

I bought a 2014 that came with an RC spacer kit that generates 3" of lift with a spacer that measures 2.25." I see Amazon spacers measuring 1 1/8" that generate 2" of lift. Seems as if the lift rate is progressive but it shouldn't be because the spring isnt being compressed. Right?

I'm asking because dealer threw in TRD coils and shocks that I want to install this weekend but not sure. if I should install a spacer at all. As it is right now, truck sits nose up with the RC kit of +3" in the front (25" hub to fender) and +0 in the back (24" hub to center. I carry tools in the bed)

Ideally either looking for level or tiny bit of rake.

 

The lift from a spacer is not a 1:1 ratio. Spacer kits are okay for onroad use but they ride rough. As far as the coils and shocks that they gave you, can you post a pic of the them? I'm wondering if it's just the offroad package from the Sport model, but I don't think it provides any lift. The Fox suspension from the Pro provides lift, but they won't give those away.

 

No it's the yellow bilsteins that come with the TRD offroad. Black coils.

I guess that's my question. Is there a ratio for the lift height vs the spacer height because it seems like there isn't and it's progressive but it doesn't make sense.

 

FYI for any future DIYers.
Took out 2.25” RC spacer that was intended for 3” of lift. Pulled the coil and spacer.

Starting height with spacer fender to center of hub was 25”.

New factory coils on trd yellow bilsteins + 1/2” of spacer yielded 24.25” fender to hub.

Swapped the 1/2” of spacer to 1/4”. Sitting at 23.5” height. Lookin good.