I have a very incomplete Chummy on which I have so far failed to locate any numbers, in some cases due to repairs such as prop tunnel. I am reasonably certain that it is either an AD or AE.

Having looked in the Source Book the text states that the AE is longer and wider (I assume this refers to the space for occupants) than the AD. However the dimensioned drawings are the same for both!! It would seem that a 'prunting orrer' has occurred but to which model do the length and width 4'10" x 3'6" apply? It has 'letterboxes' so won't be an early AD.

Any help, however vague, greatly appreciated.

Cheers, Derek.

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Derek

Yes, I too had noticed that the Source Book may well have the incorrect drawing for the AD. I have an AE which is indeed 42” across the body at the rear of the doors (‘B’ post in modern parlance). I believe the corresponding dimension on an AD is 39½”, but whenever one pokes a head above the parapet it generally gets shot off!!! However a quiet measure at rallies would indicate that this is probably the case.

A quick guide is the protrusion of the rear wings at the top of their curve. On an AE they stick out only 2”, and thus on an AD this will be three and a bit. This is a noticable increase.

I have never investigated the 4'-10" that you mention, but it refers, according to both drawings, to the distance between dashboard and inside rear of body at the waist rail.

Mike

My 28 AD (63712)is 39" inside from top of the body slam pillar across to the other side. Original body

Mike, Ian,

Thanks very much for your comments.

Next problem is to persuade the bits to maintain a reasonably correct relationship to each other for long enough to confirm the measurements :-(

Derek

Mike, you are correct about the incorrectness of the Source Book. Factory drawings show as per your measurements. As for the length dashboard to rear of tub - it hasn't varied much since the first model as although the say '23 Chummy had an overall shorter body, the scuttle was much shorter -ie- the dash was further forward than the later jobs. Confused? Cheers, Bill in Oz

That’s surprising Bill, I had no idea that was the case. We live and learn.

Derek, May not be relevant to your car if it is an AE, but my AD is 56 ¾” from top of dash to the inside of the rear aluminum beading, the wings are 3 1/8” out from the body at the wheel center. The scuttle is 16 ¼” from door edge to rear of bonnet measured just below the screen pillar. Inside from hood stanchion position is 38 5/8” and from the hood rest position is 37 1/8” across the body. Door aperture is 25 1/8” Doors on AD have half round beading; on AE the door panel overlaps the body with no beading.

Hi again Ian. It's surprising how many measurements re-occur on various models of Sevens. Your 56 3/4" is 56" in a 1923 Chummy, which as I said is fairly close; your Chummy windscreen is same width as that on a '23 and an Ulster; the "flat" part of your Chummy front floor is the same length as that on a Nippy, etc etc. The "greater passenger room in a Chummy" only came with a slight width increase over the years. Cheers, Bill in Oz.

Hi Bill, That’s really amazing, I always thought that the pram hoods were tiny compared to my AD, as I say ‘you live and learn’