Spring rates, I want better then stock.

[notnodak]

I've got a new 3905 E-Maxx with a Ammo 36-56-2600 motor w/ single motor mount/cover, MambaMax esc & Losi DSM radio, everything else is stock.
I am not happy with the stock springs and want stiffer ones. My question is what is the stock spring rate?
I had a combo of 4 stock and 4 Proline two piece progressive springs off the
Powerline shocks on my old E-Maxx and loved it. Can i just get RCBROS/RCRaven progressive springs and be happy or should I get a stiffer spring? I could drop my old fully RTR E-Maxx from 3ft and it barely bottomed out. I do it to my 3905 and it slaps hard.
Also what weight oil are you all using to get more wheelies and smooth things out? I understand that 50 weight would smooth things out some and let it wheelie better.