This is the kit for the 383: It comes with speed pro cast flat top pistons.

https://shop.enginekits.com/osb/itemdetails.cfm?ID=81

Also, the comp cam tech line recomended this cam:

http://www.compcams.com/Cam_Specs/Ca...x?csid=92&sb=2

This one is a little more agressive than the one you recomended. Do you think that this cam is to much?