Rojo2...
Maybe they're getting the 3" drop when using the V6 springs under a V8 truck?
I do know that the V6 ones are different part numbers from the V8 springs.
Before I'd even bought a 400, I began gathering parts to lower one. A bud that had had a 454SS when they were new, had plans to lower it, but never did. Gave me the set of dropped spindles & 2" lowering springs out of his stash.
But with my truck being a 6, those springs only dropped it maybe 1.25". Looked like a dog stooped to poop. You know, 'that' look! Lol!
Bought some 2" drop springs for a 6. Hated 'em. They wouldn't put up with my antics! Way too soft.
Dug out the factory springs & cut 1 coil. Ended up being maybe .125" lower than the aftermarket drop springs. Those werre fairly new when I pulled them. Maybe they needed to settle in a bit more with some mileage.
So yea, I can see how the different springs used under different versions of the trucks would yield different results.
I did all this before this forum even existed. Kinda stumbled around in the dark trying to figure it out. One thing for sure, I've gotten good at tearing the front end down!
But since I've been here, the general consensus is that 1 coil = 2".