how much cam can stock valve springs handle

1bad67sbf

Active Member
Nov 24, 2010
674
1
29
N. VA
i got this cam
https://www.lunatipower.com/Product.aspx?id=2513&gid=309
•Advertised Duration (Intake/Exhaust) 270/280
•Duration @.050" (Intake/Exhaust) 204/214
•Gross Valve Lift (Intake/Exhaust) .448"/.472"
•Lobe Seperation 112
•Intake Center Line 107
•RPM Range 1200-5200
i want to know if i can keep the stock springs or if i have to upgrade? i feel its a small flat tappet cam so it should be fine but i want to be shure first. (its an older block and will only be in my mustang for a year or so then i will put my roller motor in) thanks for any help
 
  • Sponsors (?)


Even with a cam that small I would expect some valve float at the upper rpms. New valve springs are cheaper then a rebuild. Better to play it safe IMO.
 
i have a set of crane springs i got for a .498 lift cam i had but never used. now i need to pick if i want to put them on the heads on the engine or just bolt the 1966 289 heads they are on to the motor. i did a mild port to them and put the springs in but never used them. i think they are like 55-57cc or something. thats going to bump the CR up but how much are the e7's cc?