What is the main benefit of using roller rocker arms in the valve train?
What is the main benefit of using roller rocker arms in the valve train?
The main benefit of using roller rocker arms in the valve train is: reduced friction and wear. In this example, a cylinder head’s valve guide diameter is specified at 0.250″ (6.35 mm) plus or minus 0.0005″ (0.013 mm).
Why are roller tips important for performance rocker arms?
Performance rocker arms typically have needle bearing fulcrums and roller tips. Roller tip rockers are a must with high lift ratios because of the increased arc of travel the tip of the rocker follows as it opens and closes the valve. The roller tip reduces the sideways thrust and scrubbing on the tip of the valve stem.
What are the rocker arms in a pushrod engine?
The rocker arms in a pushrod engine serve two purposes. The rockers serve as fulcrums to redirect the upward motion of the lifters and pushrods into downward motion to open the valves. The lift ratio of the rockers also serves to multiply the amount of valve lift generated by the cam lobes.
What kind of rocker arm for exhaust valves?
The latest offering is a new Roller Tip I-Beam rocker arm for exhaust valves. The rocker can handle engine speeds in excess of 10,500 rpm and withstand the high loading created by extreme exhaust pressures in these engines. The rockers are made from billet 4340 steel and heat treated to 305,000 psi.
Why do I need a rocker for my valve train?
There are also several factors to address when setting up the rocker system to insure proper operational stability and alleviate any possible clearance issues with the valve train so let’s take a look at some of these areas.
The rocker arms in a pushrod engine serve two purposes. The rockers serve as fulcrums to redirect the upward motion of the lifters and pushrods into downward motion to open the valves. The lift ratio of the rockers also serves to multiply the amount of valve lift generated by the cam lobes.
Performance rocker arms typically have needle bearing fulcrums and roller tips. Roller tip rockers are a must with high lift ratios because of the increased arc of travel the tip of the rocker follows as it opens and closes the valve. The roller tip reduces the sideways thrust and scrubbing on the tip of the valve stem.
When to use rocker ratio or push rod?
When utilizing higher valve lifts through cam lobe design, rocker ratio or a combination of both, using a push rod that has a 210 degree tip radius will provide additional clearance between the rocker cup and push rod and eliminate the chance of the push rod binding during operation at these larger lifts.
There are also several factors to address when setting up the rocker system to insure proper operational stability and alleviate any possible clearance issues with the valve train so let’s take a look at some of these areas.
