What size socket for 1927 Standard series spark plugs?

Working on a 1927 model 26-S. I'm going to have to grind down the outside of a socket to be able to fit it over the spark plugs. The 13/16ths one that I ground down years ago for the 1924 Buick that I used to own is too small for these plugs. Before I start grinding down and ruining more sockets, can someone tell me what size the socket is? 1-inch seems like it will be too big, but I can't fit anything over these plugs due to lack of side clearance on the engine, so it is nearly impossible to judge.

Pete Phillips, BCA #7338

Leonard, Tx

Pete, I have the long spark plug sockets which have the narrow walls, so they don,t need grinding down. 7/8 fits the smaller pugs and 15/16

fits the larger one,s

Pete :

On my 1925-25 Standard it is 15/16". I bought 2 - 7/8" Tool kit thin wall type sockets at Hershey which were very sloppy fit on my 1937s plugs. I probably looked at hundreds of these over the years but never a 15/16". So I want to try to heat them with a torch and open them up to fit. One for me and one for Dave Blaufarb's 1928-25. Yes the engineers did not provide much space for a socket. You should see the cobbled device I made to check compression.

Best of luck:

Larry

Pete :

On my 1925-25 Standard it is 15/16". I bought 2 - 7/8" Tool kit thin wall type sockets at Hershey which were very sloppy fit on my 1937s plugs. I probably looked at hundreds of these over the years but never a 15/16". So I want to try to heat them with a torch and open them up to fit. One for me and one for Dave Blaufarb's 1928-25. Yes the engineers did not provide much space for a socket. You should see the cobbled device I made to check compression.

Best of luck:

Larry

Compression tester I had came with a rubber end on it so it was a universal fit... which was great up until the point the buick ingested it (least my compression was good!)

We didn't have any issues using a regular spark plug socket but it may have been a metric one that was 'close enough'