VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1929-1932 Valve rocker arms

What is the length difference between the rocker arm from 30-31 to 1932, can I use the 32 arms on a 1929 block with a 30-31 cylinder head
Thank you in advance for answers

The rocker arm ratio is different for 1932 rockers.
If you are using a 1930-1931 head you should use those rockers on that head.

Rockers from 1929 are also able to be used, but 1929 valves will not suit a 1930-31 head.

If you use '32 rockers you will also need to use '32 shafts and standoffs as the diameter of the shaft and ID or the rockers is larger in '32. The longer rocker arms will position the pushrods next to the outer side of the hole in the head. All that assumes that the other end of the rocker will fit on the valve stem properly (not completely sure about that, might be able to check later today if someone else doesn't already know).

Here is a picture of the push rods in the top it says 30-31, rocker arms 30-31 length, 34.5 mm. from the center of the axle to the outer end of ram, what is it that I have overlooked.
[img:center]http://chev.mono.net/10144/rocker%20arms[/img]

The increased rocker arm ratio is achieved by shortening the pushrod side of the rocker arm, and/or lengthening the valve side of the rocker arm. So therefore your photo shows the rocker arm on the push rod too close to the pushrod hole on the inside edge. I believe that on the 1932 head the mounting holes for the rocker studs are moved over to the pushrod side slightly to compensate for the longer arm on the valve side/ shorter arm on the pushrod side.