Broken Valve Spring

I keep finding small pieces of the base of my valve springs in the valve covers after a run. What is the cause of this and does it really hurt anything. They are Manley red stripes.

 

This is common with some brands of springs. Some go as far as clipping them off when new.

 

Thanks for the help.

 

Had this once with the Comp cams 948 springs, they (comp cams) told me that there are sometimes "problems" during the heat treating process that
create this situation.
I remember that i put in a new set of 948`s and this never happened again.

BJ

 

Alot of engine builders actually deburr and polish the ends of the valve springs to remove stress risers.

 

How tight do you set your springs? (measurement to coil bind at high lift?) You're suffering from valve spring wobble-----the springs are going sideways as much as they are up and down. Ever take your grandmothers door spring and whap it? long spring--vibrates a long way and for a long time. Now whap it and run your hand down it to effectively shorten its length. Notice how the frequency changes and it finally at some point rattles and just stops? If you set your springs close to bind with a little room for error, they stop the vibration on every cycle and then start it again the next open/shut cycle instead of just continuing to rattle. Won't tell you the magic number because it cost me a lot to find it out. Send as large a check as you can afford and I'll sign you to a contract of secrecy, and then give you the number. Good Luck!

 

I suggest that valve springs should be run .050 to .070 from coil bind, Never more than that. If by doing so increases the desired seat pressure beyond your limits, Pick a differant part number spring that is better suited for your application.
Ken Juszczyk

 

I believe your describing "spring surge".

 

The valve spring gets blamed most of the time when spring failure occurs, but most of the time the source of the problem is some where else in the system.
In this case it is a possibility that the stability of the valve train assembly is limiting the maximum engine speed and at the point of spring surge the tails are coming off the spring. The amount of impact energy that it takes to do this is very high and other damage is taking place.
Using a different valve spring may help. By changing the frequency of any major component may cause the assembly to calm down.
Just a guess but I think the frequency of a 049 spring is in the area of 27500 cycles. The frequency of a PAC 1355 is slightly higher than 30000. The PAC1360 is higher than 35000. The rule of thumb is the higher the better.
Stiffening every component of the system will allow the maximum engine speed to be increased.

Noel Manton

 

Ken, why did you give out the numbers? I've been standing out by the mailbox freezing my tukus off waiting for the checks to arrive! I would have split the money with you 60/40 if you'd just asked. Making money off your fellow racers is good---NHRA does it every day. Now you've ruined my one chance at riches and fame and given it away for free. What do you think this is: America? NHRA has trained me to live in a totalitarian state. I can't handle all this freedom!

 

My heads came Fresh from Brad after having a seat replaced.....they are setup @ .060.