Factory heads?
 

I'm seeing a lot of builds building just the short block and using head studs. How rough and tough is the factory valve springs?

Haven't done any research on this but...
I haven't seen any of these broken yet, so I assume fairly strong.

I know Full Blown has stage 1-3 head packages (hehe), so the need has been identified. They also push 700+ hp though, so maybe the OEM head is only an issue at those levels.

@FullBlown, at what level did the head become an issue?

Doing valve springs helps keep the rockers from shooting out the valve cover. We do them on every built motor and check that the lash is correct

the factory springs are far too light for any reasonable amount of boost
if you're rebuilding the engine I'd swap them out for something heavier

[QUOTE=gramicci101;2696432]I know Full Blown has stage 1-3 head packages (hehe), so the need has been identified. They also push 700+ hp though, so maybe the OEM head is only an issue at those levels.


Head packages are a serious thing..... hehe

If going high power, a lot of people have swapped the valve springs. Some people have actually broken a spring. If you are 300 HP or less probably not needed in most cases,from what I have read.

I agree with that - although the standard spring cover is so small that even a stock engine would benefit from a slightly heavier spring to help with over-rev's
my analysis showed a max safe rpm with the stock cam is 7800rpm....

admittedly a loss of valve control is something that you can often get away with for a while until the valve head falls off 10,000 cycles later

I was about to interject/ask about this mysterious relationship of valve spring rate to power but fortunately you came into the picture. :thumbsup: