Hi all,
I am trying to set the suspension up on the Twini. I would like a bit more feel in the front as it floats around a bit. I am going to increase the caster, but would like to know what others run?
For other settings I have about ½ degree negative camber all around, and a touch of toe in front and rear.
I know it's not the normal Mini, but am interested in any thoughts.

If you can dial in some more camber ... -1.5 degrees and 5-6 degrees of castor ..

Beanie

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I am the son of the STIG

HOTBRICKS
http://hotbricks.org.au/

'65 NCF MINI.....
'69 MINIMATIC.... 9 year resto still on the go

camber wont give you the sense of feel you are looking for but the castor certainly will. That will affect how much the car wants to straighten up out of a corner. Check your toe setting as well both front and rear. Standard is enough on the front, and you would want a little toe in on the rear or it will feel skittish in the back end. If there is added weight in the bum you may want to stiffen up the back-end but thats just a guess. Speak to Fred Sayers. He races a twini and would be offer better advice.

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1970 Cooper S ex-Bathurst & ATCC
1964 Austin Cooper S ex-Group C race car
1967 Morris Cooper S ex-Group B
1962 Mini Speed sports sedan
1968-71 ex-Peter Manton Shell car

Fred Sayers? - Anyone have his contact details?

I reckon you want a little toe-out on the front, as it's a standard Mini setup there.

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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.

Fred doesn`t race the twini normally, it`s Billy Westermans thing

& they`ve been playing with the handling for quite some time, only lately have they had any glory & i`m not sure they`re totally ontop of it yet

& if you have "toe-in" at the front then i`d set that to --> "Toe-out" first, maybe 1/16th to start with

& yes about 4deg of caster is fine for nearly every occasion

But!!!... the camber depends on a pile of things-->

what tyres you run

what spring rates you have

how stiff the body-shell is

your driving style

& what you`re using the car for

-->but a half deg would be good for starters , just to get you feeling things out

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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.

very interesting... with the extra engine in the back it'd be like driving a normal mini with a heavy (over the ball) trailer, or 6 bags of cement in the boot. I've done both of those, and I think I know the floaty feeling you're talking about

can you stiffen the back-end?

maybe hydrolastic top arms at the back and rubber top arms at the front...

I would leave the camber and castor alone for a while and just play with the toe settings.
I think that most of the feel will come from that area.

I like the comparison to the heavy trailer on the rear.
I will try a few bags of cement on the bonnet and see what differance it makes .

i can tell you that (after you`ve sorted your light/loose/darty front end) that you may want to play both front & rear bump steer... Billy & i have had some awesome disscussions & have played around a fair bit on the rear & found remarkable improvements with his twinny doing this

i can`t say much about your particular car as i havn`t driven it,,, & you may not have the same type of limited-slip rear diff as Billy does,,, but it`s definately worth a look at if you have any trouble with it being too pushy, then suddenly changing to too loose

bump steer on all minis isn`t pretty, they`re not a perfect geometry by any means, & when i set-up my rack on my buggy i made sure it had "ZERO" bump steer,,, yep,,, you read it right--> "ZERO" !!!! & it`s just awesome to drive,,, perfectly stable , very predictable, & it just does everything i want it to,,, so this is where i`d spend my time with your car, setting up the bump-steer (front & rear) as best you can (once you`ve sorted the light front end of course)

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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.

The Twini is set up as a road car, and is very neutral to drive. No pushing and pulling, minimal understeer or overseer.
The engines have the same power / torque curve (well so the dyno states) and are set up to accelerate in unionism. Both hit WOT at the same time. Standard diffs front and rear, and obviously the same gear ratios. Two orange clutch’s which is a little heavy in the traffic.
There is a little bump steer from the rear. Hit a pothole, and it takes a small step to the left (or right). I have no easy way of adjusting this so will live with it. What car doesn’t move a bit when you hit a pot hole?
As for the normal alignment settings, I will have the caster set to around 6 or 7 degrees, and a touch of toe out front and rear, with ½ degree negative camber all around. Hopefully this makes the difference I am after.
It will be interesting to see how Bills car goes when he has it sorted.
Thanks for all the ideas – See you in Hay

i`d just have toe-out at the front only

the rear i would set at either 1/16th toe-IN , or set it straight ahead

i don`t like toe-OUT at the rear of any car (but that`s just me) especially if it`s already stepping out over bumps

i`d definately be making the rear arms with adjustable mounting points to set the rear bump steer tho, placing the rear-outer steering joints (for want of a better description for the things) in the spot where the least bump steer is possible,,,but again , that`s just me.

have fun man & hope all goes well

Bills Twinny is allready pretty awesome so i think he`ll probably leave it how it is now, just my guess tho.
cheers
Matt

edit--> Oh & sorry i won`t be at Hay, no license, no time, & no money

Looks like i won`t even get to Valla for the big VW meeting this August either

i`m a sad sad man right now

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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 reckon straight ahead toe at both ends. For equal balance cars (like Alfa GTV's with a transaxle - guy I work with has one and thinks it's the best car ever built), they have their wheels straight up and down and straight ahead. If there's any alignment issue they'll bump steer

bump steer at the back will also mean squat and droop steer.

I'll see you at Hay - I looked at your car at Minis At The Mill a few years ago (2009 maybe?) and was very impressed. Was GR doing your motors a couple of months ago? if so, I was there when he dyno'd the second one

Well,
Set the Caster to 6 degrees,
Camber -1/2 all around,
And a touch of toe out on all the driven wheels.
Tracks well on the road and handles the bumps with minimal bump steer.
Did the tip to Hay and back without issue.
Can't say the same about my driving skills and two WD's at the moterkhana, but it was great fun.