1.3 rockers

[el tee eff]

What is the advantage to the 1.3 rockers? Why are they used&when?or in what circumstances I should say?

 

[el tee eff]

Someone told me they take the lift&duration of the cam&times it by 1.3,is this true? I thought the ratio rockers were used to keep geometry inline with a big lift cam.
I am just curious what they actually do.
Thanks in advance for any info.
L Todd Fischer

 

[Ftrchamp]

It will add lift. If your cam has say .242" lift you would multiply .242" x 1.3 and that would be your lift.

 

[W5R]

They are basically used to get the advantage of more lift without using a big cam, like said above you would multiply the lift times the ratio of the rockers. They are an easy way of getting close to .300 lift with a stock cam. But, where cams have the advantage over rockers would be the profile of the cam....lift, duration, lobe separation. Ratio rockers do not increase duration much if at all, or change the lobe separation of the cam, they increase the lift at the valve and maybe the ramp. You have to be careful and check for coil bind when using ratio rockers, they can and will coil bind, especially when you have a big lift cam and not enough spring.

 

[James Dotson]

They give you more lift than stock and at a faster rate than using a bigger cam. You generally need heavier springs and preferably stronger push rods.