I got this ute load mini stuff and among it
is these two heads.
One is a 12G202 and the other is a
smog CAM 4004.
I would like to port one for my MG1100.
But I also have a 1175 block which I will
build at a later date, so which modifies best
for these motors

The 12G202 has bigger, better shaped ports to start with so less work to get the same HP.
The CAM4004 will port out OK too, it just takes longer and time is $$$.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

So the 4004 has more meat in it to remove
but the result is about the same.
Thanks Doc.

When porting either of these heads, would I expect to
find the water jacket in the same spot?
Um? I just read that. Er...I really don't want to find
the water jacket, but you know what I mean.

I'm still looking at this head.
I measured east/west across the ports
the widest is 67 mm.
Yes they all varied by about 1.5 mm.
My question is this:- Is it possible this head came off a
1275 as the ports seem too wide for a small bore?
This head shows no signs of modification.

They are both smallbore heads, won't work properly on a bigbore block.
Where did you measure 67mm??? Head gasket?:?

_________________
DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

Across the widest part of the chamber on the face of
the head

Well on a smallbore 850-998-1098 the chamber overhangs the bore in one direction, and the block in the other (where exhaust valves are).
This is normal.

_________________
DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.