#21  
Old 09-26-2021, 10:02 AM
Bill Hanlon's Avatar
Bill Hanlon Bill Hanlon is offline
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Quote:
Originally Posted by 65sport View Post
So who are you challenging ?
Kenth's statement about vacuum advance at 4500RPM.

He implies that there would be 20 degrees of vacuum advance applied at that engine speed. He also states that vacuum advance starts at 8-10 in/hg vacuum. I believe that the only way to get that kind of vacuum at 4500 RPM is either:
a. no-load (holding 4500 RPM with the clutch pushed in, why do this?)
b. no-load (accelerating past 4500 RPM , then closing the throttle)

In my opinion, maintaining 4500 RPM under load (especially in high gear) will require enough throttle opening that the 8-10 in/hg required to begin vacuum advance will never be reached.

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  #22  
Old 09-26-2021, 04:00 PM
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Kenth Kenth is online now
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Quote:
Originally Posted by Bill Hanlon View Post
Kenth's statement about vacuum advance at 4500RPM.

He implies that there would be 20 degrees of vacuum advance applied at that engine speed. He also states that vacuum advance starts at 8-10 in/hg vacuum. I believe that the only way to get that kind of vacuum at 4500 RPM is either:
a. no-load (holding 4500 RPM with the clutch pushed in, why do this?)
b. no-load (accelerating past 4500 RPM , then closing the throttle)

In my opinion, maintaining 4500 RPM under load (especially in high gear) will require enough throttle opening that the 8-10 in/hg required to begin vacuum advance will never be reached.
If you want to know what is going on with vacuum advance at all rpmīs and driving situation just connect a vacuum gauge to the intake at a full manifold source via a long hose so you can watch wile driving.
Simple as that.

FWIW

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