I think my Dad's XK120 (post war) used Whitworth. Steve? You had
one, is this true.
JC
______________________________ Reply Separator _________________________________
Subject: Re: Crossmember Bolt Tech Tip
Author: cobra-at-cdc (cobra@cdc.hp.com) at HP-ColSprings,shargw5
Date: 2/11/98 9:23 AM
>
> BTW, are the stock bolts really 1/2 x 20TPI? The same guy who suggested
> that grade8 had lower shear strength than grade5 also suggested that the
> stock crossmember bolts were Whitworth. At this point I think that
> information is also suspect. But, I ran a 1/2 X 20TPI tap down one of the
> holes to clean out all the gunk and afterwords it seemed like the stock
> bolts fit slightly looser than a new 1/2 X 20TPI bolt I had laying around.
> Thought I'd ask before running the tap down the other three holes.
Not likely Whitworth. Whitworth fasteners were used mostly pre war,
though some can be found on just post war cars- my old MG TD had more
than a few. One possibility is BSF, but 1/2 BSF has 16 threads/in
(Whitworth has 12/in). If you should find some BSF threads somewhere,
don't rush to clean them up with an SAE tap or die. The threads are cut
differently and you could end up with a sloppy fit. In case you're
wondering why I know all this crap, it's 'cuz Cobras have lots of BSF
fasteners.
Roland
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