Once again after a little help.

Things are progressing well on my supercharge set up but some one raised a question.
With the extra power what kind of top end speed will I be looking at from my Metro gearbox. Is it worth investing in having a fifth gear jammed in there?

Is the standard gearing on the Metro (as this is the motor set up I have) that different to the Mini?

On most Mini 5 speed boxes I've heard it said that 5th is the one most heavily loaded, and `likely to wear' if turbo or blower or a BIG bore motor is used.
Basically, the bearing setup in any Mini box is not designed for extended use in the indirect (including 5th) gears.
Proper 5 speed boxes (eg Alfa, Fiat, BW T5, Supra etc) that are designed that way all have real ball or parallel roller bearings on the cluster gear, not crappy little needle rollers running on a shaft made from dubious quality steel....

Solution? I'd forget 5 speeds with all that torque U got- just fit a taller diff- 3.1 or 2.7 etc.

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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've heard other comments similar to Doc's regarding the 5speeds that are availible for mini's.

dewey

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dwightgunning.com

Sounds good, and cheaper which is always nice.

Cheers

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Make it faster...
Make it harder...
But make sure it's a Mini!!!!!!!!!!!!!!!!

So, basically, the 5 speeds are only if you have a slightly warm 1275.. hmm. Considering I was thinking of going the 5 speed option. Basically I had allowed about $4k for the engine and $4.5k for the box. Might have to rethink that now. Wonder if I should put the money into an alternative engine..

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You're only supposed to blow WHAT off?

My thoughts exactly a_m_a_d_a_a_m. Gees that's hard to type.

2.7 ratio top gear 4500 rpm 160 or 170 cant remember now long long time ago
makka

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Anonymous moderation means the agro that is built up towards the mods isn't aimed at an individual (fewer "Makk" attacks). Less stress for mods means less moderator "retirements".

you'd need something pretty beefy to pull a 2.7 wouldn't you? Wonder how it would take off in first. I'd love to test drive a car that had a diff like that. I've considered it or a 2.9 but wonder about how viable it really is. Take off would be a little slower but revving it out a little in between gear changes and it wouldn't be that noticable, would it? I don't know.. brain liquifying here...

yes, I didn't think about typing it all the time when I came up with the name but...

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You're only supposed to blow WHAT off?

If I remeber correctly Jan's mutant mini (the car, not the forum member!) runs a 2.9 or a 2.7 with a torquey 1380cc? It goes very well anyway!

My mate's stock MPi powered Mini has a 2.9. It is a little slow off the mark, but once it gets moving it is not a problem.

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Brett Nicholson
Greendale (near Ballan) VIC.
1971 Morris Mini Moke
1966 Austin Mini
1965 Morris Mini Traveller
1973 LR Series 3 88
2007 LR Freelander 2

Where abouts on the diff can you find what ratio it is? Does anyone know what the standard Metro (non turbo) is?

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Make it faster...
Make it harder...
But make sure it's a Mini!!!!!!!!!!!!!!!!

Which Metro?

There were different ratios on different models, ranging from 3.44 on the MG to 2.7 (or 2.75??) on some economy models.

Generally I think they were 3.2 on the 1275 manuals. But the only really accurate way is to remove the cover and start counting teeth.

Someone else here may know more than me, I've only just started deliving into A+ stuff...

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Brett Nicholson
Greendale (near Ballan) VIC.
1971 Morris Mini Moke
1966 Austin Mini
1965 Morris Mini Traveller
1973 LR Series 3 88
2007 LR Freelander 2

I'm thinking about building a 4 synchro SCCR box because I've already got a gearset- but if I keep the 3.44 diff (10" wheels) with its 2.5:1 1st gear ratio I might get outdragged at the lights. Can't have that.. can we?
So I'm thinking maybe a 3.64 or 3.76, and some new earplugs!
Oh bugger, the speedo will read even more wrong too..

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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.

hi i have put a 2.65 diff ratio in my mini. it has a 1100 motor with twin sus, electronic dizzy, 1.5 rollers, high compression ported and polished head and ive had it to 5900rpm in 4th and it scared the crap out of me. if anyone would no how fast this is id like to no i still havnt got the speedo recalabrated. i think it would be close to 200?

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i like to drive on rails

The only way it could get to 200 is if you slipstream someone.
Download a program called gearcalc http://www.locost7.info/gearcalc.php it makes it very easy to work things out.

Probably about 170-180...tops

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