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Old 15-09-2014, 02:52 PM   #16
MiniLandy
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Interesting ideas, I like the use of the metro parts. I take it you're going with custom lower arms, how are you making them up?
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Old 15-09-2014, 03:05 PM   #17
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As I said before it's inspired from other builds,
For now I'll probably just weld some thick plates on the existing arms and reinforce them. Then I might use poly bushes rather than the standard. Just means I have all options. It's mostly a road car but some fun when required.
Also means parts are easy to get. Trying to minimise specially made parts where possible.
I'm also using the lower arm rubber bushes as engine mounts at the mo. Seemed sensible to keep them the same!
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Old 16-09-2014, 10:09 AM   #18
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Don't suppose anyone has some rear mgf lower arms and hubs?! Got some theories to test!
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Old 16-09-2014, 05:32 PM   #19
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Had a quick measure of the sump clearance and it is approx 10cm at the lowest point when I have a wheel to arch (wing) clearance of 6cm
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Old 23-09-2014, 08:25 AM   #20
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I'm constantly fighting with myself over weather to use 10 wheels or stick with the mgf brakes and 13 wheels 😥 😣
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Old 23-09-2014, 09:31 AM   #21
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If you are desperate for 10's then obviously the MGF stuff has to go...

But with your likely power level (250hp ?) I would prefer the hub level offset that the R100 / MGF stuff gives over the A series setup.

As you will have seen I deliberated the same in my build diary

Will post a little more later when I get back

Cheers
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Old 23-09-2014, 04:51 PM   #22
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Hi Ed,

The K Metro hubs with ET40 offset (I am using ET44) and above wheels will be the best for resisting torque steer

If you want it to be as light as possible then 10s and ally knuckles / hubs

Wheels like the rosepetals are available in ET40 in 10s but still not as good as the K Metro stuff for reduced hub level offset.

13s have better tyre choices, 185/60 & 175/50 and more terms of different manufacturers / specs,

If you did stick with A series knuckles & hubs just try and keep the wheel offset to as high a positve ET as possible, you can get companies like Compomotive to make ET40 and above in 13s to suit A series hubs if you fail with the 10s

Cheers
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Old 23-09-2014, 07:53 PM   #23
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Cool! Thanks for that!
Yeah that was really why I went with the mgf stuff to start with, stronger parts, better angles, bigger brakes as standard.
I just can't stop thinking banded steelies and chrome caps would be cool! 😂
Need to stick with function rather than compromising just for looks, I want the power so need the strength in the parts.

I also can't stop thinking about trying to fit the quattro bits as well! But I know it will need to move the rack and put a big hole through the bulkhead for the prop. 😢 just want minimal mods to the body.

Too many options and not enough minis!!

Tried looking at you build before bit the images don't work! 😞
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Old 23-09-2014, 08:04 PM   #24
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Hi Ed,

If you mean my current build, it's here:

http://www.turbominis.co.uk/forums/i...=vt&tid=479642

The old RWD build got messed up when I sorted out my Photobucket into sections if you mean that one?

Cheers
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Old 23-09-2014, 08:56 PM   #25
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Yeah meant the rwd one! 😣
Will have read of the turbo minis one now though!! 😉
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Old 24-09-2014, 07:32 AM   #26
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I did quite a bit of work to try and see how I could make my suspension work with both A and K series knuckles with the minimum of parts needing to be changed...

Because the upper ball joint is the same fitting for the A and K series hubs it is possible to use the same upper arms for both.

In order to swap to an A series knuckle I would need to make another lower wishbone (solely to suit the A series ball joint) and then move (probably add more pick up points) the lower inner pick up points up in the frame.

The reason for moving the lower wishbone inner pick up points up is to maintain a sensible roll centre height (RCH), about 40mm up keeps the RCH the same for both set ups. Clearance between the front leg of the wishbone and the inner CV / driveshaft would be my biggest issue and would mean I may not get the full 40mm but 30mm or so looks possible.

Obviously driveshafts would need to change to suit the Mini CV and correct the length as the CV centre is in a different place.

Bumpsteer changes a little too but a couple of mm of rack height sorts this out.

Weight wise the main issue with the K series stuff is a lack of lighter weight parts, Hi Spec make an ally caliper but only advertise it as fitting with 14" wheels, I spoke to them and they said certain 13" wheels may fit depending on the wheel design and offset.

With a fully lightweight A series ally front knuckle / hub etc you save over 6kg per corner just in brakes and knuckle weight and even more with 10" wheels. So you quickly get to 20kg front axle weight saved.

My car originally had std A series based knuckles / hubs / Metro turbo 4 pots and then the weight difference is only 1 kg or less

Some of the 200hp plus A Series Turbominis still use 10s on A series hubs but IMO the K series stuff has to be a better technical solution if not the better aesthetic (13") one

Look forward to updates

HTH

Last edited by Aubrey_Boy; 24-09-2014 at 07:35 AM.
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Old 25-09-2014, 08:30 PM   #27
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Wow! Spent my spare time over the last couple days reading your build thread on turbo minis! All I can say is that it's absolutely EPIC!!
I'd be over the moon if my build was half as neat and had 10% of the thought that has gone into yours!! So many similarities!! I knew I wasn't doing everything for the first time, but there's a lot you've actually done that I have only just thought of!

Certainly made me want to stick with the k hubs and make do with 13" wheels! Although I had a guess last time I was in the garage and I reckon certain 12" wheels may actually fit! (Maybe just!! &#128514

Also I now can't stop the urge to get in the garage and do nothing else!!

If only I could move the position the steering rack slightly I might just be able to go quattro!! Then who knows what power I could handle!

Epic! Just Epic!!
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Old 26-09-2014, 08:00 AM   #28
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Thank you for the kind words Ed,

When you said the pictures didn't work it didn't cross my mind you would be referring to the old RWD thread.

When you mentioned using the R100 / MGF stuff I thought the new build thread would be much more relevant.

Just a few more points which I think are relevant to decisions you will have to make pretty soon.

Steering arms: R100/MGF or A series

In order to keep it std length round nose my first priority was to move the engine back, this caused several problems, one like you is the rack body hitting the diff casing, so the rack had to move back towards the toeboard. (I actually moved it backwards and up to improve clearance)

If you move the rack and use A series steering arms (Metro or Mini) they are much shorter than R100, this will give much more Ackerman but more importantly mean the track rods feed the loads into the rack at quite an angle which will cause the rack and / or its mounts to flex more. Ideally you want to feed loads into the rack along the rack axially (i.e. into the axial centre of the rack bar - Ackerman aside anyway)

If you use R100 steering arms everything goes back to normal (assuming you have moved the rack back 40 - 50mm) which is the correct position for a R100 rack relative to the wheel centre. That's why Watsons (Or any that use R100/MGF frames) converted cars have a longer wheelbase by about 50mm, because without modifying the toeboard / bulkhead the rack dictates how far back everything goes and where the wheel centre ends up.

Steering rack: R100/MGF or A series

Initially I planned to use the Std Mini rack assembly, when I did some suspension simulations I saw I needed to make the Mini rack wider (I don't mean track rod extensions - I mean the rack & rackbar itself wider) to get the bumpsteer more linear. At the same time I noticed the maximum steer angle of the road wheel was quite low at full lock steering wheel travel.

I checked a R100 Metro rack and my Mini rack for the amount of rackbar travel and the R100 has nearly 40% more travel, so if you use an A series rack and use R100 steering arms you get quite a poor turning circle. Discussions I have had with Denis (Evo) since have confirmed that this is the case as this I think is the set up he has

So I used a narrowed R100/MGF rack, this gives more travel and a variety of rack ratios from the different models so you can choose how heavy the steering is versus how 'quick' the steering. I am using an orange band rack, I think there is Green, Yellow and Orange (I think Red and orange are the same as I see both quoted for same racks - don't quote me tho)

I am not saying this is the correct or the only way to do it, just the compromises I chose and my findings.

The further you move the rack up the narrower it needs to be get linear bumpsteer.

If you can measure or estimate your suspension and rack pick up points I will happily run some simulations to get some idea of different configurations effect, the model I have is parametric so it's quite quick to change hard points.

Cheers

Last edited by Aubrey_Boy; 26-09-2014 at 08:03 AM.
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Old 26-09-2014, 07:29 PM   #29
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Hi spencer,
Thanks for the info!
I have both a yellow and an orange rack, I was going to narrow the yellow as a test and then shorten the orange if it worked out ok.
My diff actually clears the rack! The only reason for moving the rack was to give room to fit the quattro stuff, but having looked at it this afternoon not sure the prop shaft output would line up down the middle at the mo.

I'm looking at moving the hubs back in the arches so they are centred and I think I could get away without cutting the front wing!

Not sure what to do with the rear subframe. Make one using k series subframe or just stick with the standard mini one?!?!

Also not sure if I should use coilovers or standard cones?!?!

So many decisions and I'm hopeless at making them!! Hahahaha
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Old 27-09-2014, 11:30 AM   #30
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I'd definitely leave the Mini rear subframe as it is, by that I mean keep it based around Mini radius arms as I don't see a reason to change it really, pretty well every other option will just add weight > all assuming it stays FWD.

Wow that is a very compact engine & gearbox fore/aft wise, I guess the fact that induction is on the front means that all the space below is free for the rad right back to the block.

If you can fit everything in whilst retaining the suspension towers & rubber cones I'd keep the cones, coilovers if positioned incorrectly can have pretty poor motion ratio characteristics and will stop you from fitting ET40 and higher wheels as they will hit the coilover, when you move the coilover in to make room for the wheel / tyre it really hurts the motion ratio. You can make the upper wishbone longer so that you can fit both coilover and high ET wheels but you end up with a wide track if you go this route. This is why I ended up with inboard coilovers and to keep the track relatively narrow.

Any more progress or pics?

Cheers

Last edited by Aubrey_Boy; 27-09-2014 at 11:33 AM.
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