Anyone able to give a breakdown of rpm to km/h (eg rpm @ 110km/h) for the different diff ratios? I have tried searching the forum as I am sure it has been posted before, but I could only find a set for the P76

cheers,

CJ

My 3.647 diff & 165/70-10 A008s does 4,600rpm @ a GPS 110KMH.

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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.

I have 1975 Mini fitted with a 1380cc, 104 Cam, HIF 44, 3.1:1 diff ratio and using A+ standard Box and 12" wheels and does 100Km/Hr and sits on 3200 rpm. Makes it a pleasure to drive and also helps with Fuel economy. I have calculated that it does approx 15.5 Km / Litre. or 6.5 Lt per 100 Km. And Speedo is accurate according to My GPS.

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DID I MENTION THAT I AM THE BEST SUPPLIER FOR MINI ELECTRICAL PARTS AND REPAIRS?
"Let us remove your "SHORTS"

3.44 diff (stock S, clubman ratio), 10 inch wheels in 4th gear:

2400rpm = 60km/h
2700rpm = 70km/h
3100rpm = 80km/h
4100rpm = 110km/h
8000rpm = Jail

Approx, except the jail part, that is for certain.

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Lillee - 1969 Morris Mini K

Try guessworks website, easy to use for any combo!

http://www.guess-works.com/Tech/ratio.htm

Cheers Shane

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If it's not a Cooper S, the mini was designed to be modified!

Great site. Well I wasn't far off. I only remember it for my car only as I use tacho instead of speedo to gauge speed

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Lillee - 1969 Morris Mini K

I suspect 8000rpm would be down a big hill? Conrod Straight? May be also followed by a few pistons trying to escape

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1969 Cooper "S"
1967 Mini Deluxe
1973 Clubman Van (the fleet spare)
1978 ex 1275 LS ("Wizard" Eaton Supercharged)
2015 HSV GenF GTS(occasional drive & tow car)
2019 MINI F55 Cooper S

Lillee's done 8000rpm every gear (cept 4th) at Western Sydney Dragway, several runs

But yeah, not sure she could do it in 4th though

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Lillee - 1969 Morris Mini K

Excellent, thank you all for the replies. Looks like I need to add a new diff to the list of things I want/need to replace.

Since i will do almost all highway driving a 3.1 will probably be best if not a 2.95.

cheers,

CJ

A 2.95 will suck, it will be a dog off the line, even with a stock gearset inside.
[edit] I would go with a 3.1 or 3.2 for highway work.

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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.

I must admit my mini isn't anything special, pretty stock really 1275 twin 1-1/4 su's on 12" rims. I don't want to turn it into a real pig to drive but I would like to make it a nice cruiser (what I mainly do anyway).

I have a 3:1 in my mini on 10" wheels and I love it, still good around town and on the highway it sits well under 4000. From memory 120km is around 4000.
My twinki engine will get eiter a 3:1 or a 3:2.

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Respect mine and I'll respect yours.

I used to run a 2.95 in a 1330, 731 cam, stock head, twin 1/4's & 10" rims. Nothing to right home about off the line but once your off the mark it was great. Cruised the highway at 3300 RPM at 100kph. It was a great combo. Good around town, but you need to use the gearstick a little more than usual.
With your 12" rims a 3.1 will sit at about 3350 RPM @ 100kph!

Cheers Shane

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If it's not a Cooper S, the mini was designed to be modified!

nice, but it won't have 12's as soon as i can afford 10's

I think you will find is pretty much:

3.76 = 14.6 mph/K revs
3.44 = 16.4
3.1 = 18.1

10" wheels (which of course are not all the same diameter) - but close enough.

Cheers, Ian