[mike uz]

what brand valve springs are you guys upgrading two? what are the stock spring rated at?

 

[drodgers]

PDR's springs.

 

[Dual K20s]

stock are rated at 35psi of back pressure

 

[Bomaster238]

i think i got mine at pure diesel power

 

[plvaulter06]

mine are also from pure diesel power, the back two cylinders were a PAIN to get in and out!!

 

[jfranklin]

stock are rated at 35psi of back pressure

on an 06? or 12 v?

 

[plvaulter06]

35psi is on the 12v. The CR's defiantly have some stronger ones, don't know what exactly

 

[stevezcummin]

kind of an old thread, but i was reading my factory manual this AM, and it states
"measure the valve spring length. The approx free length is 55.63mm with the max incliniation of 1mm.
Measure the valve spring force. 65lbs is the minimum acceptable load required to compress the spring to a height of 49.25mm.
If the valve spring does not meet the limits above, replace the spring"

Hope this is of some use to someone. The manual is for a 94.

 

[timebomb]

More internet missinformation in the replys to this thread. Stock springs have a installed pressure of about 94lb the Marine spring has a beehive design and has an installed pressure of around 154lb If you do the math you will quikly find out why they are called 60lb springs, it has nothing to do with back pressure or boost.