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How Low Without Tubbing?

suspension

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#46 hhhh

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Posted 08 March 2019 - 09:16 PM

In theory, you should be able to, with the donuts and shocks out, calculate maximum bump stop crush, add a little for error, tire expansion and flex in suspension arms, and be done with it. You could make up bump stops that are one third their full thickness to simulate full crush or similar.



#47 JakesTe

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Posted 08 March 2019 - 09:37 PM

You need to mock it up with the car at its correct weight and fitted with the wheels and tyres you're going to use other wise you're just guessing.

Yeah, that is pretty much what i have come to realise... i would have thought there was a known or popular way of going about this, but i guess i will have to set it all up and play with it for a while until i can figure it out!



#48 hhhh

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Posted 08 March 2019 - 09:53 PM

I agree on having to fit the tires, but I don't see how weight is that relevant. The extent of wheel movement will be controlled by the bump stops, full stop. (Pun intended.)



#49 Bobbins

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Posted 09 March 2019 - 10:24 AM

Much of this depends upon whether you want a car that drives and handles well, or a car that aesthetically looks the way you want it to, but possibly handles like a bag of spanners (wrenches!).

My starting point would be to trim the front arches as per the MPi Sportpack cars, there's a template available from Minispares, then fit yellow dot rubber cones and Hi-Lo's all round. I'd prefer red dot rubbers but I suspect for what you're looking for the yellow dot (race) will be the extra stiffness you need to try to prevent rubbing. Try to get your head round the rubber cones being your suspension, and the shocks controlling the oscillation of the rubber, if you fit super stiff shocks in an attempt to prevent bottoming out you're going to really mess up your handling - they're not just super stiff when you hit a big bump, they're super stiff all the time. A car with next to no suspension is a pain and becomes a bore after a while. Fit a normal reduced height shock and you'll be fine with the Hi-Lo's on a low setting.

I'd then fit the arch extensions to suit the look you want, but ideally when you've finished the rest of the build and you've had a chance to give the car a shakedown and set up the suspension to handle how you want it. You may want to fit a stiffer bump stop if you're going to run very low.

#50 nicklouse

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Posted 09 March 2019 - 11:49 AM

dont cut as per the sports pack. with tens all you need to do is trim the front of the front wings.

 

stiff shocks will just jack the car down in use if they are so over damped that they can over come the spring. and to correct the above slightly. the damper controls the movement of the unsprung parts. and rubber is a naturally damped medium.



#51 DeadSquare

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Posted 09 March 2019 - 12:43 PM

May I suggest that you buy a Mini body shell, boot, doors and bonnet.  Paint is just how you imagine it.  Stand it on four block at just the height you picture in your mind and glue the tyres to the ground in exactly your desired position.

 

Then you won't have to cut any of the body work away and you won't end up with a Mini that handles like a Camel with a hang over.



#52 Bobbins

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Posted 09 March 2019 - 01:45 PM

Cheers Nick, that's what I was trying to say!

#53 JakesTe

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Posted 09 March 2019 - 02:17 PM

Much of this depends upon whether you want a car that drives and handles well, or a car that aesthetically looks the way you want it to, but possibly handles like a bag of spanners (wrenches!).

My starting point would be to trim the front arches as per the MPi Sportpack cars, there's a template available from Minispares, then fit yellow dot rubber cones and Hi-Lo's all round. I'd prefer red dot rubbers but I suspect for what you're looking for the yellow dot (race) will be the extra stiffness you need to try to prevent rubbing. Try to get your head round the rubber cones being your suspension, and the shocks controlling the oscillation of the rubber, if you fit super stiff shocks in an attempt to prevent bottoming out you're going to really mess up your handling - they're not just super stiff when you hit a big bump, they're super stiff all the time. A car with next to no suspension is a pain and becomes a bore after a while. Fit a normal reduced height shock and you'll be fine with the Hi-Lo's on a low setting.

I'd then fit the arch extensions to suit the look you want, but ideally when you've finished the rest of the build and you've had a chance to give the car a shakedown and set up the suspension to handle how you want it. You may want to fit a stiffer bump stop if you're going to run very low.

Thanks bobbins... i definitely don't want a car that drives like a bag of wrenches...

i have already bought new black rubber cones and they were a lot of money and i am not planning on buying any more anytime soon so... i have hilos and was planning on buying lowered adjustable shocks...



#54 JakesTe

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Posted 09 March 2019 - 02:21 PM

sorry guys i know this seems to be a hard question...

but i still want the car to handle like a mini should so i might not be able to go as low as i am picturing so is there like a max recommended lowered height for the hi los and shocks?



#55 CityEPete

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Posted 09 March 2019 - 04:33 PM

Race tracks are smooth,have no speed bumps or manhole covers, something that just about works on a track won't be enjoyable on the road.

#56 DeadSquare

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Posted 09 March 2019 - 04:43 PM

sorry guys i know this seems to be a hard question...

but i still want the car to handle like a mini should so i might not be able to go as low as i am picturing so is there like a max recommended lowered height for the hi los and shocks?

 

 

Talking of "handling", I don't want to be unkind to you and dash your ideas, but a Mini's handling comes into its own when driven 2/3rds or more near the limit, something that isn't going to happen often at Gt Britain's 60 MPH but perhaps Canada has a higher speed limit.

 

At racing speeds on a race track, lowering a Mini is beneficial on sweeping bends, handling is hardly an issue, so there is no point in the average driver lowering a road going Mini on public roads. 

 

Lowering can induce patter and the limited front suspension travel engaging the bump stop can violently throw a wheel off the ground on an uneven surface.

 

Sticking on fat tyres alters the steering geometry, which reduces feel, and  pushes the 2/3rds point up to 70 or 75 MPH.

 

Using a standard profile tyre with a 4 1/2" or 5" wheel on the front stiffens the sidewall, and together with about 2 1/2 degrees negative camber, will nicely increase feel;  absolutely no toe in and 3 1/2" wheels on the rear will help to get the back end out and 1 degree of negative camber will help to make it more predictable.

 

There is actually something to be gained by raising the front of a Mini;  with left foot braking, the higher center of gravity transfers weight, and thus grip, onto the outside front tyre, which is especially useful getting the car to come round in the wet.



#57 JakesTe

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Posted 09 March 2019 - 05:35 PM

I am a visual learner so it helps me to compare things to a picture...

is a mini like this one, at this height, going to be that uncomfortable on the road? 

 

personally i like stiff suspension as long as it not ridiculous! i have seen so many minis with this approximate height so i would be surprised if it is that bad... but maybe im wrong and most people with classic mini's like sore bums... i have no idea so...

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#58 JakesTe

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Posted 10 March 2019 - 11:23 PM

 

sorry guys i know this seems to be a hard question...

but i still want the car to handle like a mini should so i might not be able to go as low as i am picturing so is there like a max recommended lowered height for the hi los and shocks?

 

 

Talking of "handling", I don't want to be unkind to you and dash your ideas, but a Mini's handling comes into its own when driven 2/3rds or more near the limit, something that isn't going to happen often at Gt Britain's 60 MPH but perhaps Canada has a higher speed limit.

 

At racing speeds on a race track, lowering a Mini is beneficial on sweeping bends, handling is hardly an issue, so there is no point in the average driver lowering a road going Mini on public roads. 

 

Lowering can induce patter and the limited front suspension travel engaging the bump stop can violently throw a wheel off the ground on an uneven surface.

 

Sticking on fat tyres alters the steering geometry, which reduces feel, and  pushes the 2/3rds point up to 70 or 75 MPH.

 

Using a standard profile tyre with a 4 1/2" or 5" wheel on the front stiffens the sidewall, and together with about 2 1/2 degrees negative camber, will nicely increase feel;  absolutely no toe in and 3 1/2" wheels on the rear will help to get the back end out and 1 degree of negative camber will help to make it more predictable.

 

There is actually something to be gained by raising the front of a Mini;  with left foot braking, the higher center of gravity transfers weight, and thus grip, onto the outside front tyre, which is especially useful getting the car to come round in the wet.

 

not really sure what you mean by this "but a Mini's handling comes into its own when driven 2/3rds or more near the limit" 

we normally drive around 120 km/h on the highway, but there isn't much cornering at that speed...

this car is not at all going to be a daily driver, but a car i drive most of the time only on weekends and be for driving fast and for fun!







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