Engine ID plate mount for cars with an electric fuel pump.

It symbolizes the devine in all A series blocks. As per Spank's suggestion, refer to it as the boost gauge plinth.

Thanks.  That's the hole drilled in the flat circle. 

Anyone know what it's for?

seems like it was to jig or index the block during production that there would be more than one on this side.  No other idea here. It's gotta be really hot there with the exhaust heat.

interesting that the two which are drilled and tapped are also the ones with the open fuel pump area

the one that is not, does not

IIRC, the non-fuel pump hole 1275 A blocks were only used on Midgets from '67 ~ '73 ('64 ~ '74 Midgets used electric fuel pumps), they opened it for the '74 Midgets because the same block was being used in the Clubman GT (which used a mechanical pump).

N

This one has the casting boss but it's not drilled:


And this one is filled with goop

I can no longer get my phone to talk to my computer, so unless someone will take a text pic from me. I can't get the picture up here. Or I can em it to someone.

all of us will have to take your word for it, unless you post a photo

 Got a look today with a mirror and flashlight.  It's drilled tapped and a blind hole.  Leads nowhere.  I guess there may be a reason to one day drill it through but it would be right under the header.

I'll leave it be.

thanks.

Yup.

Go ahead and thread a boost gauge into it. Or a knock sensor. Or nitrous nozzle. They will all have the same effect.

Those are normal.

Is it the water jacket drain plug / tap ?  1/2 way down RH edge of this image.

The one on the bottom flange I always understood was a feature of the A series INLINE engines - ie in the Midget & Sprite.

Can you be more specific on where it is located - how many inches below the bottom of the head or above the bottom of the block, and is it roughly in line with a cylinder or between which cylinders? "about where LCB branches meet" kind of suggests it would be pretty low, possibly below the level of the cam, but if it is higher, it might be a coolant drain hole (a guess).

I stuck a bolt in there to see. It's about 1/2 deep. Doesn't seem to go through. I'll borrow a boroscope today.

Could it be where someone has drilled into the oilway near the oil pump to put a magnet in? Only thing I can think of. BTW, if that's not it, does it appear to go all the way through or into an oil or water way?

I've got a 1300 block and recently discovered a tapped hole in the back of the block. It sits about where an LCB header branches meet.

I think it's about 1/2" diameter. 

Any ideas as to what this is and do I need to put a plug in it?