Which is the best way to tune an 850?

[coopertim]

I'm looking to improve the performance of my totally standard 850. The engine has done a genuine 46,000 miles. The Mini has been converted to dry suspension and is fitted with Hi Lo's and will be running 4.5 'S' wheels. i would like to add a period tuning set up without re mortgaging the house

Any suggestions or items for sale greatly appreciated.

Cheers. Tim.

[vegar]

viewtopic.php?f=7&t=2162

[Simon776]

Stick a 1098 in it - that was all the rage back in the day!

[59fan]

Shorrock.

Not especially cheap but ideal for a standard 850, just bolt on and go.

Ian

[mk1]

There's a bit of info here;

viewtopic.php?f=3&t=531&p=3157&hilit=850+tuning#p3157

In general a decent cylinder head, modiofied or a 295 ground down to give a decent CR. 1.5 rockers or a mild cam swap, twin H1's, H2's or a single 1.5" carb, decent exhaust & manifold.

Will give you an 850 that can just about keep up with modern traffic & will remain reliable. Much more than this & it starts to become a pain.

Or as simon suggests stick a good 1100 in, they look the same but go much better.

[ivor badger]

What age 850? as early ones only had a front camshaft bearing and the rear at the oil pump would wearout through the block. What carb do you have?

[coopertim]

Its a May 1965 850 Super Deluxe. It has the standard original carb.

Simon thanks for the sugestion - im on the look out for a decent 1098 now!!

Mark. Thanks for the link.

Tim

[ivor badger]

Its a May 1965 850 Super Deluxe. It has the standard original carb.

Simon thanks for the sugestion - im on the look out for a decent 1098 now!!

Mark. Thanks for the link.

Tim

65, then it won't have rear camshaft bearings. Just remove the aircleaner, fit short ram pipe and EE3 needle (needle is from memory). then you won't need to bother with the 1098 engine.

[KA2S4]

Its a May 1965 850 Super Deluxe. It has the standard original carb.

Simon thanks for the sugestion - im on the look out for a decent 1098 now!!

Mark. Thanks for the link.

Tim

65, then it won't have rear camshaft bearings. Just remove the aircleaner, fit short ram pipe and EE3 needle (needle is from memory). then you won't need to bother with the 1098 engine.

He jests.

[Toby]

I should have a set of twin H1s for sale soon, they were quite a common tuning option on 850s.

Similar to these :

[ivor badger]

Its a May 1965 850 Super Deluxe. It has the standard original carb.

Simon thanks for the sugestion - im on the look out for a decent 1098 now!!

Mark. Thanks for the link.

Tim

65, then it won't have rear camshaft bearings. Just remove the aircleaner, fit short ram pipe and EE3 needle (needle is from memory). then you won't need to bother with the 1098 engine.

He jests.

Nope

[mk1]

im on the look out for a decent 1098 now!!

Funnily enough I have a very nice one out of a low mialage Austin 1100, that's complete (more or less) sitting at the back of my garage.

Contact me direct if you are interested.

Ivor is correct in saying that the 850 does not have cam bearings, but this has never been a problem on my modified 850 or any of the others I know of. It could be if you decided to use big heavy valve springs & rev it like the clappers though.

Taking off the airfilter & changing the needle will to all intents & purposes do bugger all.

[999 ORX]

Ive just bought a 63 super deluxe for my old mum to run around in and thats been 'breathed on' . Its putting out a 'wopping' 40.5 bhp and 41 pft. It has a minisport stage 3 head, 1.5 carb and RC40 exhaust. This is how i bought it but id much prefer to see it with the pea shooter exhaust on as i much perfer the sound on deceleration, but you cant have both! It is nice to keep them period though and id possibly be interested in a set of twin h1's for it if they come up for sale Masnarda .

[mk1]

The 1100 engine that I mentioned above is now sold.

[ivor badger]

Ive just bought a 63 super deluxe for my old mum to run around in and thats been 'breathed on' . Its putting out a 'wopping' 40.5 bhp and 41 pft. It has a minisport stage 3 head, 1.5 carb and RC40 exhaust. This is how i bought it but id much prefer to see it with the pea shooter exhaust on as i much perfer the sound on deceleration, but you cant have both! It is nice to keep them period though and id possibly be interested in a set of twin h1's for it if they come up for sale Masnarda .

Strikes me that leaving it std and changing the needle would have done more. Btw Mk1, have you actually tried changing the needle on an 850 HS2?

[mk1]

Btw Mk1, have you actually tried changing the needle on an 850 HS2?

No I haven't but I very much doubt it would make as much difference as the mods I suggested or fitting an 1100 engine. I am however always prepared to be proven wrong.