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PostPosted: Thu Jul 13, 2017 10:20 am 
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Joined: Mon Jun 10, 2013 9:57 am
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Location: Australia
nick rogers wrote:
CooperTune wrote:
drove a 998 with 2.95 for 100,000 miles. It was no screamer off the line but what 998 is? Got me ready for my 2.56 FD 1360 Cooper S. Steve (CTR)

What is the tooth count on a 2.56 ? And where does it come from ?

Does its take into account an "eco" A+drop gear set?


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PostPosted: Thu Jul 13, 2017 10:48 am 
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timmy201 wrote:
nick rogers wrote:
CooperTune wrote:
drove a 998 with 2.95 for 100,000 miles. It was no screamer off the line but what 998 is? Got me ready for my 2.56 FD 1360 Cooper S. Steve (CTR)

What is the tooth count on a 2.56 ? And where does it come from ?

Does its take into account an "eco" A+drop gear set?

Ah yes maybe. So a 2.7 with approx 9% drop gear advantage. I don't think I would want to use anything bigger than 10" wheels with that or hill starts might be a problem.


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PostPosted: Thu Jul 13, 2017 11:06 am 
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i am sure Jacknight did a 2.5 diff

Personally i didnt like 3.7 or above for road use

I ran a 2.9 out of a mini City E in a 1275, i liked it.

Back to a 3.44 i would prefer that in a 998 compared to a 3.77 for everyday driving and road use

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PostPosted: Thu Jul 13, 2017 12:08 pm 
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Joined: Sat May 10, 2014 11:45 am
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Location: Up north where men are men and sheep are frightened
Most of the later 998 minis ran a 3.1 diff with 12" wheels


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PostPosted: Thu Jul 13, 2017 1:36 pm 
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Andrew1967 wrote:
I run a 3.4 diff in my 998 Cooper basically to stop it revving its bollocks off at speed.

Much more civilised (if a Mini can be civilised) :? :lol:



Exactly Andrew! Do you notice much difference in the overall drive??

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PostPosted: Thu Jul 13, 2017 1:59 pm 
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Location: Mid Sussex
snoopy64 wrote:
Hi

Anyone swapped out the 3.7 for a 3.4 in a 998 Cooper?

Just sorted my speedo out and 60mph is a bit LOUD!!!

Hi Kevin,

I did exactly this when I restored mine in 1986, I didn't drive it much on the 3.7 before I tired of the blue smoke and started the restoration but as others have said many 1970s 998s had a 3.44 as standard and I figured that it wouldn't blunt the performance that much and might make it more civilized.

Never really regretted it although always had the feeling that my friend's Countryman with a 3.7 and a 1980s A+ engine was slightly quicker off the line but my extra power quickly came into play.

Having said that it's still LOUD!!! ;)

Also had one of the last City Es on 10" wheels with the A+ and a 2.9 diff, you had to rev it pretty hard but it was still fun and even better on motorways (my father once reckoned I passed him when he was doing over 90). Also drove an Advantage on 12s with the 3.1 and that definitely seemed less nippy, but the City was a good 'un! (My first car, my brother sold it with 120,000 miles on it still with the original clutch, no idea how we managed that! :o )


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PostPosted: Thu Jul 13, 2017 6:01 pm 
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Location: UK
snoopy64 wrote:
Andrew1967 wrote:
I run a 3.4 diff in my 998 Cooper basically to stop it revving its bollocks off at speed.

Much more civilised (if a Mini can be civilised) :? :lol:



Exactly Andrew! Do you notice much difference in the overall drive??


It did knock a bit off the acceleration but as has been said 998's aren't renowned for their performance.

With the revs being lower for any given speed, the car was definitely quieter even with the single box RC40 exhaust system !


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PostPosted: Thu Jul 13, 2017 7:54 pm 
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Posts: 71
Being in Cornwall I find the 3.7 diff fine as that`s all the 850`s ever had and they were great fun screaming around.

The 3.7 diff gives you 60 mph at 4000 rpm and 75 at 5000 rpm
The 3.4 diff gives you 66 mph at 4000 rpm and 83 at 5000 rpm
In fourth gear with 165/70-10 tyres

There is no point in having a camshaft that gives its best up to 6000 rpm if you`re not going to use it and small bores need to be screamed due to lack of capacity and of course its fun :)

I prefer quicker acceleration for overtaking tractors and equally slow tourists and at road legal single carriageway speed i personally can`t see its worth the aggro, just drive 5 mph slower for the same affect or be damned with it and enjoy the roar :)


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PostPosted: Thu Jul 13, 2017 9:48 pm 
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Location: Coastal VA USA
Yes, two O/D drop gears will get you there. The very wide ratio Metro 998 gear set puts guts back in first gear. The 1000 RPM drop between each gear requires a little torque to pull. Idles at 650 and pulls 96 mph at 4000. And yes I know it will do it. Steve (CTR)


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PostPosted: Sat Jul 15, 2017 9:41 am 
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Posts: 572
Location: Netherlands
Used to have a 3.1 in a standard 998 Inno Cooper block (i.e., standard 998 Cooper with usual AEA630 cam but single HS4 instead of twin HS2) in a 10" Mini. Worked like a charm both for traffic light take off's (quick to about 6800 rpm top in 2nd) and motorway (about 160kph top). I experienced it as an ideal combination.

_________________
1964 Austin Cooper S 1275
1965 Volvo Amazon Combi
1965 Austin Cooper 998
1967 Morris Minor 1000
1967 Austin Cooper 998 Mk II
1969 Austin Cooper S 1275
1972 Austin 1300GT (2x)
1975 Mini Jubilee
1978 Mini 1000


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