I think you would do better if you explained better what you want??
if you want more blood look for the blood *.jpg or *.tga (i dont remember where it is or what it is called but its some where in packages, probably in textures. For gibs there is some model some were in packages/models that is what is replaced with the pmodel (player model) when a persons health goes below or at 0. But if you are more descriptive of what exactly you would like to change about the blood and gibs I could be better at pointing you in the correct direction.
chasester
P.S. If you no anything about coding start at fps.cpp::dodamage() and then work your way around till you find out how some one switches from CS_ALIVE (health greater than 0) to CS_DEAD (health at or below 0). Which happens in dodamage() i do believe, and there is some function thats run to swap the model out for the gib model and blood added etc. So thats where you should probably change shit ;p
NOTE: dodamage() is started by the actor (shooter) and then the victim (the one that got shot) is told to take the damage (and also the server is told if it is mp [muliplayer]). The terms that i used are those used in the code and if u mess these up you may have blood pouring out of the actor when he hits something 0.0