I recently got thinking about driveshafts for my 4EFTE Conversion. The Mini I started with had drum brakes all round but now has Disc front hubs.

At this point in time, I'm considering getting the driveshafts for my conversion made from half-Mini, half Starlet shafts, with both shafts machined down, pinned & welded and an additional collar welded over the top and slow-cooled. Why this way? Well the cost of custom billet shafts is close to $1000 ... around 3 times the cost of this method.

However I want to know is there any difference between drum & disc Mini shafts (Size/diameter, strength, splines)? Further to that, would I be better off buying new Mini driveshafts (if so, from who) and use that for the fusing of the two shafts, or would second hand ones be ok?

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-Alan
I blame my dad for my love of minis. I think I was conceived in the back seat of one
I also blame my Dad for me being 6' 1" - not really the optimum height for driving a Mini.

It's been a few years now since I converted my car to discs, but from memory I just replaced the drum outer CVs with disc types, which just slotted straight onto the drive shaft, no mods required. So no, the actual drive shaft (from diff output flange / pot joint to outer CV) is the same between drum and disc Minis.

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Simon

The adventures of an owner builder in the Tallarook Ranges

The guys in the UK seem to do it that way with success - i'd be using original 60's/70's gear over the new stuff that's probably made out of cheese any day.

As the starlet shaft has lots of length in it you can cut it down and respline it but this is probably not as good as doing it the way you are saying.

You will still have the inherent issue which is the spline size at the mini CV end is too small to handle high shock loads/power and is the weak point for failure.

You can get 1 piece shafts made cheaper than $1000 over on the east coast that's for sure, at least half that.

I've gone through 4 shafts over the years all varying design/spec but it all depends on your power/drivetrain and how you drive - I will be going for bigger CV's when the next shaft lets go.

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Starlet Conversion:
http://www.ausmini.com/forums/viewtopic.php?t=15484

Who did you use for billet ones? Got to get mine made soon and if they're under 1000 to have them made id feel better going down that route, something I don't trust about the interference fit ones that get made

I'd say a cut down - respline is the best way.
The shaft stays lighter (less rotational mass), easier to balance, and a single piece of material is always stronger than a welded object.
The reason that this could fail is if the new spline is cut in and a long runout up the shaft not machined in, no large fillets where possible and incorrect heat treatment / hardening applied.

I think the main issue with cutting them down is that the starlet shafts are very hard from the factory so they are difficult to respline - very few would have a tool that can cut a spline into heat treated steel therefore they need to soften it and reapply the heat treatment which never really works out that well as it becomes brittle.

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Starlet Conversion:
http://www.ausmini.com/forums/viewtopic.php?t=15484

Yeah we get shafted (pun intended ) in WA in so many areas. My quotes for a custom radiator is a prime example (The 3 quotes ranged over $780-950 for a ~350x350mm radiator) where in Qld Tricky paid ~$400 for the same thing.


I'm not going for big HP (std engine & CT9 turbo w/ 2 1/4" dump pipe & exhaust & 12psi boost) and I'm not a drag strip whore. The boost setup will be more gradual when coming on boost rather than hard the "big spike on boost" setups. All this I hope will contribute towards less of a shock to the drivetrain & driveshafts when under power.

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-Alan
I blame my dad for my love of minis. I think I was conceived in the back seat of one
I also blame my Dad for me being 6' 1" - not really the optimum height for driving a Mini.

Yea but you guys are making all the money over there

I think you should be fine with that setup - the biggest issue for me is the heavy duty clutch setup which is quite direct in getting the power down. It's the launching and wheelspin from fast shifts/popping the clutch that will kill them - but it's oh so fun

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Starlet Conversion:
http://www.ausmini.com/forums/viewtopic.php?t=15484

Ask around your race circles i'm sure they would know a few local engineering shops - I got my turned down in the shape from bar stock on a lathe, then took them to get splined (matched to the CV's i was using) and then took them to another place to get heat treated - this way I had control over each step end to end.

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Starlet Conversion:
http://www.ausmini.com/forums/viewtopic.php?t=15484

Drive shafts are one of the next things I am going to do as it gets me that little bit closer to being possible to drive it.
I have recently had my hubs built and asked about bigger cv's, the answer I got was that the morris 1100? cv's are bigger but are much harder to get and are more expensive. Then something needs to be taken off the hubs to fit them.
I decided to go with mini cv's but am not looking forward to replacing them or the drive shafts if they keep going bang

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If you want more inches, stroke it
Life's a garden.... Dig It!
http://www.ausmini.com/forums/viewtopic.php?t=20746

Gordo for your build order some AllSpeed HD CV's

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Starlet Conversion:
http://www.ausmini.com/forums/viewtopic.php?t=15484

Morris 1100 CVs are just the same as Cooper S or Rover Mini ones.
Morris 1500 had larger ones but I think they were a bit longer 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.

Ahh yes that makes more sense

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If you want more inches, stroke it
Life's a garden.... Dig It!
http://www.ausmini.com/forums/viewtopic.php?t=20746

yeah the 1100 ones are the same Gordo,,, it`s the 1500 ones are bigger, & longer , but they don`t fit all the way into the hub because they`re so big in the bell.

you "Either" have to grind the hub out immensely or space the cv back inwards a tad

i have your new CVs here btw

edit--> when you`re up here next i`ll show you the difference, i have a few 1500cv joints here so you can compare

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No offence intended here but--> anyone writing a book about minis 30 years ago may not have experienced such worn or stuffed-with components as we are finding these days.

You should put your heart & soul into everything you do.

I wasnt sure which cv's it was that were bigger, I'll try and lock 1500 ones into the memory banks now but im not promising anything
Since getting a new job and living down the coast I dont really make it into Brisbane all that much anymore. Next time im up ill have to call back in for sure. The van is sitting in the corner of the shed now, waiting for some much more needed time

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If you want more inches, stroke it
Life's a garden.... Dig It!
http://www.ausmini.com/forums/viewtopic.php?t=20746