a little help with carbys for my 850 would i be best suited to keeping with the 1 1/2 su or go upto 1 1/4 dont want speed just good fuel consumption wat difference would it make also wat other things might i have to change if i went with the 1 1/4

ah,,, "up"???

1&1/4 is smaller than 1&1/2

_________________
No offence intended here but--> anyone writing a book about minis 30 years ago may not have experienced such worn or stuffed-with components as we are finding these days.

You should put your heart & soul into everything you do.

The auto 850s in UK had a 1-1/2" SU and higher compression- it added around 3HP to offset the auto transmission losses.
This trick was also used on the auto 998 (and auto 1098 in Morris 1100)

All manual 850s had a 1-1/4", as Matt said.

[edit] Fuel economy with a 1-1/2 if jetted right will be hardly any different.

_________________
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.

ooops!!! sorry guys got ma sizes wrong way round ma bad lol.. ok now i have the answers i am looking for thanks to you both for youre help