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FE Power Forums => FE Technical Forum => Topic started by: BigBlueIron on January 14, 2021, 10:33:49 AM

Title: Rocker ratio
Post by: BigBlueIron on January 14, 2021, 10:33:49 AM
Anyone ever mix 1.73 and 1.76 rockers to help crutch a camshaft? Say a single pattern that your stuck using.

 I know not hardly enough difference in ratio to be worth it or even notice a difference.
Title: Re: Rocker ratio
Post by: blykins on January 14, 2021, 12:38:58 PM
Depending on the camshaft, you wouldn't see much difference at all.   On something like a .500" cam, you're looking at about .009" difference.  On a .600" lift cam, you're looking at about .010".  In some instances a higher rocker ratio will accelerate the valve opening quicker, but going from 1.73 to 1.76 doesn't have much there.
Title: Re: Rocker ratio
Post by: GerryP on January 14, 2021, 01:39:27 PM
Anyone ever mix 1.73 and 1.76 rockers to help crutch a camshaft?...

That's within machining tolerance.  It's an insignificant difference.  If you have a solid cam, you can always tighten or loosen lash to test affects.  You can't do that with hydraulics, though.
Title: Re: Rocker ratio
Post by: Rory428 on January 14, 2021, 05:25:30 PM
Depending on the camshaft, you wouldn't see much difference at all.   On something like a .500" cam, you're looking at about .009" difference.  On a .600" lift cam, you're looking at about .010".  In some instances a higher rocker ratio will accelerate the valve opening quicker, but going from 1.73 to 1.76 doesn't have much there.
  And thats assuming the rocker ratio is actually the same as advertised, which at least with OE rockers, is rarely the case. On my 302 Mustang Stock Eliminator car, the advertised rocker ratio is 1.60, in testing dozens, I never found any even close to spec, the majority were 1.53-1.54.