I just though that with I am using the car for these would be a little stiff. It will be a daily driver with maybe 6 or 8 trips to the strip a year. I am going to set my rev limiter at 6800 even though the cam will rev a lot more then that.
I know I am overly concerned with the spring pressures with the aluminum heads. I would have no problems running these springs with cast iron heads.
I am also concerned with the cam issues other people have had.
With this in mind I have a 40 year old set old springs from a 390 that I will use for break in. They should be good enough for 3000 rpm for 30 minutes
Never had a cam issue but I don't want one now.
Greg
Greg,
You would not have to worry about those springs on an aluminum head and that's not the issue that raises a flag in my mind. FWIW, you can run up to 600 lbs open pressure on an aluminum head and you're about 7 miles away from 600 lbs with those springs.
However, the issue is that they may be too stout for the camshaft. 140 lbs seat is starting to ride the fence on too much spring pressure for a street camshaft. With that being said, if you could give the cam specs and engine specs, I can tell you how high the cam will go and if the spring pressures are warranted. Keep in mind that we really don't judge how aggressive/lazy a cam is by looking at the lift by itself, nor does that really play into how much spring pressure is needed.
I run 160-170 lbs seat and over 400 lbs open on solid flat tappets, but they require special oiling lifters and other options.