Hot Rod Forum : Hotrodders Bulletin Board - View Single Post - Broken inner Valve springs Dart Iron Eagle SS Heads on Chevy 383 Stroker
View Single Post
  #9 (permalink)  
Old 12-29-2012, 04:08 PM
MouseFink MouseFink is offline
Registered User
 
Join Date: Jun 2010
Location: TX
Posts: 1,149
Wiki Edits: 0

Thanks: 0
Thanked 101 Times in 93 Posts
You can see in the photo that the valve spring seats are too large for stock valve springs. A stock single valve spring with a damper is 1.265" O.D. to 1.300" O.D. and those valve spring seats are at least 0.200" larger in diameter.

A spring that dances around on the seat at high RPM due to spring seats that are too large will fail. That is probably the #2 reason why valve spring fail. The #1 cause is coil bind or inadequate assembled height for the valve lift your cam has.

You may have both problems if you do not know how much valve lift your camshaft has.
Reply With Quote
The Following User Says Thank You to MouseFink For This Useful Post:
techinspector1 (12-29-2012)