Quote:
dazza1200 wrote:
polish the stockers and shot pein them
heaps lighter!
Shot peining them does not make them lighter but may marginally improve the strength.
Polishing also, of itself, does not add lightness [???] however removing material from the rockers in the right places before the other processes will reduce the weight fractionally, but does nothing about the rocker arm ratio or the friction & resultant lateral loading of the valve in its guide during the valve opening phase.
The true roller rockers are lighter by virtue of their alloy construction.
They also have less frictional drag on the shaft by virtue of the needle roller bearing at this point.
They are also made with a higher lift ratio than stock rockers so you get a little more lift at the valve without changing cams.
The roller tip virtually eliminates the friction &drag across the face of the valve stem so valve guide wear is reduced [in an exact comparison with stock rockers] & a tiny bit more friction is eliminated at this point.
Lets summarise.
Roller rockers offer lower rocker arm weight without compromisung strength, they reduce friction at two important points, they reduce side loading on the valve thereby increasing valve & guide life & finally they need less oil to provide proper lubrication.
On the downside is the price, particularly when you include the custom pushrods that will be required. For a new instalation, all inclusive, you had better have $1,000 or more in your pocket.
Transfer
