Typical vacuum reading for 1929?

[jps]

For a 1929 Standard (small) engine, what range of values should I see on a vacuum gauge installed into the intake manifold during cranking, and also during idling at about 1500 rpm, if everything is normal?  I don't see any relevant info in the manuals that I have.

 

Thanks

 

John

[michealbernal]

17 in to 21 in Hg at sea level is normal vacuum.  It also going to depend on whether you are using the vacuum fuel system.  That will cause it to fluctuate some.  If you go to Greg's Engine and Machine web site they have a detailed article on what the various vacuum readings are telling you about your engines performance 

[ply33]

1 hour ago, jps said:

For a 1929 Standard (small) engine . . .  idling at about 1500 rpm . . .

 

That sounds awfully high for idle RPM on a car of that vintage. Did Buick have that fast an idle on their cars back then?

[hchris]

8 hours ago, ply33 said:

 

That sounds awfully high for idle RPM on a car of that vintage. Did Buick have that fast an idle on their cars back then?

 

Hmmm sounds alright to me, what values are you thinking? 

[maok]

2 hours ago, hchris said:

 

Hmmm sounds alright to me, what values are you thinking? 

More like 400-500rpm idle speed.

[ply33]

5 hours ago, hchris said:

 

Hmmm sounds alright to me, what values are you thinking? 

Around 500 would seem typical for the era. Seems maok and I have the same number in mind.

[Mark Kikta]

I like the way my 1922 sounds and runs at around 600

[hchris]

17 hours ago, ply33 said:

Around 500 would seem typical for the era. Seems maok and I have the same number in mind.

 

Ok, read the question again and realised the value was for crank over rather than running. I'm assuming we're measuring downstream of the throttle.