So I'm buliding a new 440 short block, and I want to use the Indy-SRs that are currently on the engine that I'm running. The current motor has a hydraulic flat-tappet cam with .545"/.545" lift and (I believe) 285/297 duration. The cam that I'm wanting to put in my new short block is a solid flat-tappet cam with .540"/.555" lift and 294/302 duration. Indy claims that my current springs are good for up to .650" lift. Do I need to change out valve springs?
I'm trying to do this swap on the cheap, so it'd be really nice if I could save a couple of bucks.
Thanks for any help.

unless the new solid flat is wicked custum grind that requires 135 seat, the sprngs you have will be fine, and you will now have less coil bind when you add lash that bigger cam will have less lift at valve unless you 1.6 it

You need to find out what the Indy heads have for spring pressure and what your cam requires. Thats the right way to know if it'll work together.