Stock valve springs
Posted: January 5th, 2009, 3:59 am
I put a dail indicator on a stock valve spring on cracked 0331 head that I have. I was able to get a little over .550 before the spring bottomed out. The head is nasty dirty, covered in oil mixed with antifreeze. So I don't know how much more I could have got with the valve springs cleaned. I also don't know how close to the retainer got to the valve guide. If you subtract a .060 safety margin, the stock springs should be good for about a .490 lift. That's enough for most high torque cams that folks are using.I am not reccomending that someone use stock springs on a performance cam, just some info for those building a stroker on a budget or concerned about wiping out a cam with higher spring pressure from some of the aftermarket performance springs.
I didn't have a stock rocker arm to see how much lift it could take before it started to bind. That is something I would want to check before I used the stock rockers on a high lift cam.
I didn't have a stock rocker arm to see how much lift it could take before it started to bind. That is something I would want to check before I used the stock rockers on a high lift cam.
I forgot about calculating it. I even had a spread sheet laid out so all I had to do was plug the numbers in, which I had.