Author Topic: Rocker Ratio  (Read 1472 times)

Offline don melvin

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Rocker Ratio
« on: September 16, 2016 - 05:58:25 pm »
Hi guys, I got a question. I have a set of mopar small block adjustable rocker arms on my 340. How do you tell what the ratio is? Does anyone know for sure? I've heard several theories. Can someone please help? Thanks




Offline GoodysGotaCuda

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Re: Rocker Ratio
« Reply #1 on: September 16, 2016 - 06:13:00 pm »
Should be 1.5:1.

To know for sure you can just measure the ratio. How much the lifter/cam moves compared to movement at the valve stem.

With a 1.5 rocker ratio, if the cam had 0.500" lift, it would move the valve 0.750".
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Offline 73restomod

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Re: Rocker Ratio
« Reply #2 on: February 04, 2017 - 07:36:23 pm »
Using a set of calipers, measure from the center of rocker shaft hole to center of roller tip, then measure from center of the pushrod cup to the center of the rocker shaft hole, divide the first measurement by the second. should get you pretty close.

Offline HP_Cuda

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Re: Rocker Ratio
« Reply #3 on: February 04, 2017 - 11:30:10 pm »

Most likely 1.5 but as everyone said go ahead and measure.
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Offline moper

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Re: Rocker Ratio
« Reply #4 on: March 04, 2017 - 11:00:47 pm »
They're listed as 1.5s but like most production items they aren't made really accurate. The tests I've seen have them from 1.45-1.5. Easiest way to tell for sure is just measure them.