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Wondering as i'm not at all familiar with them,what can you do to an 850 to get some go out of it?

Reason for asking is rally of the tests and several other classic events cut off (for overall results) before the S came out, so it's an 850 or a 997 Cooper (if you can find one )..

Smallest Mini engine I've experienced was my 998cc Cooper which went alright to be fair to it.

Brynmor wrote:Wondering as i'm not at all familiar with them,what can you do to an 850 to get some go out of it?

Reason for asking is rally of the tests and several other classic events cut off (for overall results) before the S came out, so it's an 850 or a 997 Cooper (if you can find one )..

Smallest Mini engine I've experienced was my 998cc Cooper which went alright to be fair to it.

Hi Bryn, suggest you obtain a copy of:

"Building and Racing an 850 Mini" by Clive Trickey

Published 1969 by Cars and Car Conversions

Everything you need to know is here.

Regards

Eddy

I've found that changing the head for a 295 and fitting an 1 1/2 SU & extractor exhaust is all thats required to easily get 100mph out of an 850. it's quicker than most modern cars from a stand still all the way to the end.
you will have to get the right needle or re-profile one (as i had to) to get the fueling right.
there are great improvements yet to be had by re-graphing the dizzy as well (still yet to do). I've got all the bits, just got to spent the time, its just too hot here at the moment (regularly over 104º every day)
and i didn't even change the cam, that'll get changed for an AEA 630, when i pull the motor to freshen it up. It's just hard to take the car off the road as it's just such a pleasure to drive

greyghost wrote:I've found that changing the head for a 295 and fitting an 1 1/2 SU & extractor exhaust is all thats required to easily get 100mph out of an 850. it's quicker than most modern cars

BOLLOCKS!

Off a cliff maybe

i did say most.
probably because most people round here drive like old grandma's, and I'm not easy on my engines either.

Add a Shorrock C75B supercharger and go chasing 1275Ss. Might be some rally eligibility snags, although it is a proper period modification.

John

Vegard wrote:

greyghost wrote:I've found that changing the head for a 295 and fitting an 1 1/2 SU & extractor exhaust is all thats required to easily get 100mph out of an 850. it's quicker than most modern cars

BOLLOCKS!

Off a cliff maybe

Glad you said it before I did !

"I've found that changing the head for a 295 and fitting an 1 1/2 SU & extractor exhaust is all thats required to easily get 100mph out of an 850..."

Just to put that in perspective..... Off the shelf the standard 1071S did around 92 mph with 70 HP (Autocar 5 Apr 1963 Pg 560).

So we can expect something like 50 extra HP from a head/carb and cam?????

Sorry mate....

Cheers, Ian

i was working on my 1275gt a number of years ago, and instead of hitting a lump of metal, i hit my dog in the balls,never mind the 100mph top speed, he hit 0 to 60 in under 2 secs!

Just found this old thread...interesting...

http://www.atfreeforum.com/mk1mark/view ... um=mk1mark

a up bryn, give jim at r.a.c.e a ring and ask him the spec on my 850, tell him i told you to ask, the main thing is quality pistons, i managed to find some schmidtt +60 nos, but was very lucky, i have some oversize hepolites if you interested, as i said , ask jim to tell you what we done we hoping for 50+ hp

a good friend of mine named bruce logan raced a 850 mini in 60's in england and was on the ccc "team" he's been in the usa for years and still has his scca 1275 mini race car which also was very sucessful. i'll call him and see if remembers what mods he did

I have a couple of mini chums. One who was in Mini racing in the very beginning (before British Vita spoiled it) and another who worked in ST Abingdon.

The latter was talking about how quite a few of the chaps had Coopers and S and were into their tuning. One of the chaps had a Marshall Cabin Blower (rootes supercharger) and lashed it up in his passenger footwell. (850 with magic wand). I recall Bill saying they melted a couple of pistons and may have had problems with fuel in the oil but it was MUCH faster than someone's tuned 1275S.

They also had a Landcrab with a V8 in it out of something. He fits boilers now.

I'm surprised they fit. Steam powered, I guess?

Tim

There is lots of good info in the other thread that is linked earlier.

Also Slowboys suggestion of contacting RACE Is very sensible.

The weakest link in any 850 is the pistons, finding a good reliable set is not easy. Always balance everything as finely as possible a good head is essential, as is a good cam I would go for a good old single 1.5 SU and a cooper 3 into 1 exhaust system, you don't need anything really fancy.

You will NEVER Make an 850 feel like a 1275 unless you either turbo or supercharge it, neither of which will be allowed for historic rallying. But you can make it into a reasonably quick, tractable, little engine that will run & run.

Concentrate on reliability & smoothness rather than out & out power. Remember to finish first, first you have to finish!

M