A lot of older cars seem to have used SU carbies at some time or other. What, if any differences are there between the non mini ones and the ones that were originally fitted to mini's? I know the manifolds, control rods and needles and seats would change between models, is there anything else and what are the easiest ones to modify for use?

Different parts, needles, this that and everything.

"SU carburetters tuning tips and techniques" has a section at the back for all part numbers for most SU's on most cars.

Weirdest stuff I've come across, is the HIF6 range. Most HIF6's from various cars are very different to each other. Mostly in dash pot height.

<edit> for Ben Afford's SC12 kit, from my experience in carby hunting, the best I've found to fit under the bonnet, in the HIF6 range are a volvo type, and the one I got myself, one from a Rover 3500 V8 car.

_________________
1964 Morris 850, 1330 Supercharged - 81.8hp atws.
1975 Leyland Mini S 1100S powered - Nice and reliable.
1977 Leyland Mini LS - Project LS-T

You need to be careful of the float bowl angle apart from the usual jet/needle tuning issues. Some carburettors were used on differently aligned manifolds. I think MG carbs and manifolds are a good example.

_________________
SooperDooperMiniCooperExpertEngineering

All garage work involves equal measures of enthusiasm, ingenuity and a fair degree of irresponsibility.

What changes the difference in the angle? Is it the bowl or the carby body?

_________________

The differences are the angle of the manifold and the way the carby sits on it. A HS6 carby of an Austin 1800 is virtually flat on its manifold and the fuel bowl sits directly up. Whereas on a mini the manifold is on an angle (13 degrees, I think) and the angle position of the fuel bowl is different so that the fuel bowl also sitting directly upright.

If you put a flat mounted HS6 on an angled mini manifold (and bolt it to the engine, of course) the carby will leak fuel every where because the float will not be resting against the needle and seat to stop the fuel flowing.

From memory, you need a different adapter between the carby body and the fuel bowl to get the angle right. Not a big job but the carby doesn't just bolt onto a mini without some fiddling.

That's that little plastic anti-vibration ring thingy right?

Earlier models of carb are more difficult.

_________________
SooperDooperMiniCooperExpertEngineering

All garage work involves equal measures of enthusiasm, ingenuity and a fair degree of irresponsibility.

_________________
David L


My greatest fear in life is that when I die my wife will sell my Mini and tools for the price I told her I paid for them!

Thanks, another book to buy and reading to be done.