It's often not the engineer who has the final say, it could be
more likely the bean-counter, eccentric-owner,
entrenched-mgmnt-bureaucracy or lately some accommodation for
assembly automation. (Also, the odd time, an engineer gets bad
advice from his wife or kids).
In the case of our LBC's it was a mix of leftover steam age habits
and the curious English phenonenum known as shelf engineering
where the car engineer goes to the accessory suppliers, looks at
what they've got on the shelf, picks up a sample and designs the
car around it and thereby avoiding tooling costs on low volume
production. (Can't blame the little buggers if some models didn't
stay low volume).
My guess is your fuel pump mounting studs back in the 30's were
originally smaller diameter and were then simply enlarged along
with the flange holes as the English so slowly moved away from
1/32 and 1/8 and 3/16 bolt/nut hardware or conversion from
Whitworth.
If you want completely accessible engine bays, buy a Model T.
Mike L (P.Eng, PT)
60A,67E,59Bug
>Just like that first day I cursed the engineer that
> figured the stud spacing. I'm not sure who I am cursing, the
engineer
> that designed the pump or the engineer that designed the hole in
the
> block for the pump. One of them had to accommodate the other
one's
> stupidity in making the studs too close together. If any of you
are
> familiar with Machinery's Handbook, there is a section that
gives
> specifications of clearance for tools when you design a mounting
stud.
> Obviously this idiot never saw this chapter.
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