A mate showed me these 2 master cylinders the other day , they have been marked with texta on the bases so i'm assuming they came off the same car (Cooper S maybe ) , can anyone shed some light on what they may of come off ?

pre '70 ish standard mini - not Cooper S - the clutch MC is the same for all minis, but Cooper S has a taller (by like 1") brake MC tank

measure the bore and someone will know more, the brake MC came in different bore sizes

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did I tell you that I won a trophy?

My '67 Deluxe has this type.

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67 Deluxe
Dry suspension
1293cc, 11:1 comp, RE 282 camshaft, 45 Weber, extractors etc
4 synchro close ratio gbox
Cooper S brakes, no booster
Stealth box, as Doc says "goes harder and idles!"
RH tank cos I needed it crossing the Nullarbor etc..

I'll get the mate to measure the bore sizes , both cyl's are the taller brake size , seems like that they have both come from the same car seeing as they have been marked with
texta , the one on the right marked brake , the other marked clutch .

Just curious that maybe a mini of some version may of had 2 tin master cyl's of the same height .

The master cylinders can usually be identified as clutch or brake by the mounting flange position.
Brake cylinders have the mounting flange holes "square" across the tank; clutch has the holes at an angle to the tank.
The usual bore sizes are 0.70" for brake and 0.75" for clutch but there are some applications where this isn't the case.
The clutch tank in you photo looks like a tall brake cylinder, but for the clutch.
Is it possible someone has had the cylinder resleeved? When tin tanks are resleeved, the tank has to be removed for drilling 2 transfer ports in the new sleeve. Then the tank has to be soldered back on. Has a PO liked the look of matching tall tanks and had the tank soldered at a different angle to be the clutch?

The Cyl's haven't been sleeved previously , when he first showed me I thought that they were both brake cyl's , it's highly possible that someone replaced both their cyl's with 2 brake cyl's .

Great explanation Bill B

Looking at the cylinders I would say they are the larger type as there appears to be a big blank distance between the top and bottom of tank and the writing, compared to the smaller cylinders, morris 1100's I have wrecked in the have had larger cylinders on both brake and clutch

If 1100s had the large tanks for both m/cs, then that is most likely where Goodie's samples came from.
I wasn't aware of what was fitted to 1100s.