Higher ratio rocker arm?

General engine tech -- Drag Racing to Circle Track

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Tom68
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Re: Higher ratio rocker arm?

Post by Tom68 »

88bluestar wrote: Sat Mar 18, 2023 7:51 pm Would smaller vacuum port diameter make a difference. Hidden plug inside a 3/16 port with a much smaller hole?
A one way valve in the fitting and a little throttle blip.
Ignorance leads to confidence more often than knowledge does.
Nah, I'm not leaving myself out of the ignorant brigade....at times.
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Baprace
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Re: Higher ratio rocker arm?

Post by Baprace »

If your idle transition slots are exposed because of a big cam , the throttle plates may be open too much and your fuel mixture idle screws will not work correctly, that will lower the vacumme , you may have to drill one hole in each plate on the transfer side , that will let too much air into the engine and raise the rpm's , now back the throttle down with the idle speed screw and adjust your idle screws out approx 1-1/4 to 1-1/2 turns and your vacumme read should go up. I would try one .090 hole in each plate for starters. Camking mentioned to keep the ignition timming advance curve short as possible and keep the timming high , that will help also. He also mentioned increasing the valve lash a tad also helps , perhaps just set a loose zero lash + .001 - .002 should help.
88bluestar
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Re: Higher ratio rocker arm?

Post by 88bluestar »

What if there’s a hole already in the butterflies?
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Re: Higher ratio rocker arm?

Post by Geoff2 »

Enlarge it in 1/64" increments until the T slot position is correct. Or....you can drill a new hole in each b'fly, 3/32".
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