I have a 1973 351 windsor that i am putting a set of gt heads on. I am wondering if there is any way to tell what cam i have with out pulling it out. second question is will i need to replace it or will i be able to run it with these new heads. the heads are off of a 1995 5.0 mustang. The engine is going into a 1977 f150 4x4 that i pulled a straight 6 out of. I use it as a daily driver and on occasion i pull a 2 place trailer with 2 snowmachines on it.