Cam choice

-
Mopower71

Mopower71

Speed Demon
Joined
May 31, 2004
Messages
2,183
Reaction score
39
Location
Poughkeepsie, N.Y.
How big of a cam can you run with stock pistons for the 1968 440 without leaving marks on the piston.
LOL Did that with the 383 with a 509 cam and bad springs. They floated a little bit and left little tell tale marks on the pistons.
 
I pulled apart a 74 440 with a .525" compcams 305H. It had valve marks on the pistons. Duration comes in to play also not just lift.
 
Too many variables to just guess. A 284-.484 probably would work. but have the heads or block been cut? What about head gasket, how thick? Installing it straight up or advancing or retarding it? Big valves or standard? How good are the valve springs? How high you gonna rev it? WAY to many variables. Put some light checking springs on #1 with a dial indicator and see how much room you have now to make an educated guess. Unfortunately, you can't know for sure until you put the cam in the motor.You need at least .090.
 
dusterdon said:
Too many variables to just guess. A 284-.484 probably would work. but have the heads or block been cut? What about head gasket, how thick? Installing it straight up or advancing or retarding it? Big valves or standard? How good are the valve springs? How high you gonna rev it? WAY to many variables. Put some light checking springs on #1 with a dial indicator and see how much room you have now to make an educated guess. Unfortunately, you can't know for sure until you put the cam in the motor.You need at least .090.
Click to expand...

i agree!!!!
 
dusterdon said:
Too many variables to just guess. A 284-.484 probably would work. but have the heads or block been cut? What about head gasket, how thick? Installing it straight up or advancing or retarding it? Big valves or standard? How good are the valve springs? How high you gonna rev it? WAY to many variables. Put some light checking springs on #1 with a dial indicator and see how much room you have now to make an educated guess. Unfortunately, you can't know for sure until you put the cam in the motor.You need at least .090.
Click to expand...
Heads and block are stock/uncut and stock valves 67 closed chamber heads on a 68 440.
 
You must log in or register to reply here.
-

Back
Top