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Have You Seen Any Interesting Cars On The Road Lately?

Bellow said:
I've been reading Mallock from circa mid 1980s and he reckoned that a Formula Ford chassis of the era wasn't torsionally stiff enough for tuning the chassis with anti-roll bars. Is that your experience of FF chassis?
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Yes, all FF cars use front and rear ARB's and are very sensitive to those adjustments. When I worked at Palmer Sport in Bedford one of my jobs became to try and make all the Caterham 7 cars handle the same. They were ragged on permanent basis, and despite being set up to the same settings, they were anything but the same to drive depending on how far the chassis had been 'tweaked'.
The adjustable antiroll bars were one of the main weapons we used to make the cars at least similar, and I got a huge insight by driving them the as to real difference dampers and ARB's could make.
 
Mactech said:
Yes, all FF cars use front and rear ARB's and are very sensitive to those adjustments. When I worked at Palmer Sport in Bedford one of my jobs became to try and make all the Caterham 7 cars handle the same. They were ragged on permanent basis, and despite being set up to the same settings, they were anything but the same to drive depending on how far the chassis had been 'tweaked'.
The adjustable antiroll bars were one of the main weapons we used to make the cars at least similar, and I got a huge insight by driving them the as to real difference dampers and ARB's could make.
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This confuses me. If FF chassis (and I really doubt that a Caterham Seven chassis is any torsionally stiffer) is responsive that implies that the chassis is torsionally stiff. Unless, what is being done is to eradicate the roll from the ends of the car at the same end - at source. At the same end as opposed to trying to absorb it at the other end. If at the same end, the need to transmit roll from end to end would be eradicated and thus any flexing of the chassis with it. That would remove its effect as an undamped spring. Is that how FF chassis are set up and/or how it played out with the Sevens?

Overarching view on damping? When can it be minimised? Is it used to circumvent other chassis failings?
 
Bellow said:
This confuses me. If FF chassis (and I really doubt that a Caterham Seven chassis is any torsionally stiffer) is responsive that implies that the chassis is torsionally stiff. Unless, what is being done is to eradicate the roll from the ends of the car at the same end - at source. At the same end as opposed to trying to absorb it at the other end. If at the same end, the need to transmit roll from end to end would be eradicated and thus any flexing of the chassis with it. That would remove its effect as an undamped spring. Is that how FF chassis are set up and/or how it played out with the Sevens?

Overarching view on damping? When can it be minimised? Is it used to circumvent other chassis failings?
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Most spaceframe chassis have all the torsional rigidity of cooked spaghetti….relative to a carbon structure! If the structure is very stiff, you can get away with just one ABR normally at the front to allow the the best possible traction from the rear driven wheels. I did this on the Gp C Jaguar cars. A combination of a massive V12 to control in roll and the torque of that same engine led me to a massive carbon drainpipe on the front and just a little light trimming on the rear.
Gordon Murray followed the same thinking on the McLaren F1 road car, except he left the rear off completely!
On the space frame flexiflyers both ARB’s contribute to overall stiffness but in proportion to where you want the grip to be …and when. Data can show on flexible car that roll angle at the front is not always the same as the rear….

Dampers are a whole book on their own. My biggest understanding of the whole subject was that low frequency ( that is low damper shaft velocity) is what controls the car relative to the ground, and that high frequency controls the wheel relative to the car.
Obviously there is both bump and rebound damping, but once you have grasped that concept you can start sorting what sort of compromise you want in your system. And it always will be!
 
Mactech said:
Most spaceframe chassis have all the torsional rigidity of cooked spaghetti….relative to a carbon structure! If the structure is very stiff, you can get away with just one ABR normally at the front to allow the the best possible traction from the rear driven wheels. I did this on the Gp C Jaguar cars. A combination of a massive V12 to control in roll and the torque of that same engine led me to a massive carbon drainpipe on the front and just a little light trimming on the rear.
Gordon Murray followed the same thinking on the McLaren F1 road car, except he left the rear off completely!
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Thanks Mactech - that is my understanding of using ARBs to 'tune' the chassis. I came to it before realising that FF and spaceframes generally are as weak as they are.
Mactech said:
On the space frame flexiflyers both ARB’s contribute to overall stiffness but in proportion to where you want the grip to be …and when. Data can show on flexible car that roll angle at the front is not always the same as the rear….
Click to expand...
The car that always led me to that (the above) thinking was the (original) Lotus Elan. I just don't buy that its backbone chassis has sufficient torsional stiffness to tune the chassis as discussed. Rather, the front and back were treated as separate entities to control their respective roll tendencies - with enough roll stiffness at the front to control the mass there and the rear the same but not overdone to the point of compromising traction. Not that traction is overly tested with circa 125hp. Chapman it seems did such a good job with roll centre location and spring rates that ARBs at either end were not required.
My main question is answered - namely, forget attempting to shift roll from one end to the other with a steel spaceframe. Another method is required.
Mactech said:
Dampers are a whole book on their own. My biggest understanding of the whole subject was that low frequency ( that is low damper shaft velocity) is what controls the car relative to the ground, and that high frequency controls the wheel relative to the car.
Obviously there is both bump and rebound damping, but once you have grasped that concept you can start sorting what sort of compromise you want in your system. And it always will be!
Click to expand...
That might be the very first time I've read that damping has to be considered in two contexts! Invariably, only one is ever discussed at a time.
 
Bellow said:
That might be the very first time I've read that damping has to be considered in two contexts! Invariably, only one is ever discussed at a time.
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This really came to light during the active damping era of F1 the height and attitude of the car had to be controlled for aero. It was then discovered that what the wheels did relative to the car to give mechanical grip was in a very different frequency range than roll, heave and pitch.
Obviously that technology was banned, but the take away, was that dampers and their tasks were much better understood.
The Le Mans winning Jaguars of the 80's leaned very hard on just getting the dampers to control the aero.
The Bentleys in the 2000's had dampers which allowed us the keep the cars in their aero window, and achieve better mechanical and tyre grip.
Those cars could 4 stint on their narrower Michelin tyres than the more powerful and much less aero restricted Jaguars.
 
Mactech said:
This really came to light during the active damping era of F1 the height and attitude of the car had to be controlled for aero. It was then discovered that what the wheels did relative to the car to give mechanical grip was in a very different frequency range than roll, heave and pitch.
Obviously that technology was banned, but the take away, was that dampers and their tasks were much better understood.
The Le Mans winning Jaguars of the 80's leaned very hard on just getting the dampers to control the aero.
The Bentleys in the 2000's had dampers which allowed us the keep the cars in their aero window, and achieve better mechanical and tyre grip.
Those cars could 4 stint on their narrower Michelin tyres than the more powerful and much less aero restricted Jaguars.
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Damping is a can of worms for another day (I know, it was me who asked)! Thanks though for the chassis stiffness info - a big help to me. Much appreciated.
 
Bellow said:
Damping is a can of worms for another day (I know, it was me who asked)! Thanks though for the chassis stiffness info - a big help to me. Much appreciated.
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Oh! I don't consider dampers to be a can of worms.....but then again I don't suppose it's everybody who has a damper dyno in their garage:dk:
It is actually in my son's workshop now, but it was in my garage until quite recently. Outrageous, I know, but I now keep cars in mine:cool:

IMGP0533.JPG
 
Mactech said:
Oh! I don't consider dampers to be a can of worms.....but then again I don't suppose it's everybody who has a damper dyno in their garage:dk:
It is actually in my son's workshop now, but it was in my garage until quite recently. Outrageous, I know, but I now keep cars in mine:cool:

View attachment 176703
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Fair enough, not a can of worms - more a black art to me! It is a strange thing damping though. I get what its two roles are but given that I've probably driven many more underdamped (than over or even correctly damped) vehicles I've never been too troubled by its absence. Annoying when a mid-corner bump sets the chassis off and takes time to settle I concede, but I've kinda found that if I'm 'committed' (but smooth) with my inputs than the vehicle goes and stays where I want it. In the back of my mind there's the possibility of damping being slower than the cars desired movements (eg in an S bend) and the damping preventing spring extension and keeping the tyre from the tarmac in the transition from L to R or R to L. I like a car to settle into its cornering attitude quickly - and be willing to change direction again just as quickly. In my head I see damping intruding on that. More intuition (witch craft!) than science I admit - a properly damped car could possibly/probably change my thinking.
I kinda have my head full of ARB tuning right now to open the can of black art damping right now though!
 
Mactech said:
My biggest understanding of the whole subject was that low frequency ( that is low damper shaft velocity) is what controls the car relative to the ground, and that high frequency controls the wheel relative to the car.
Click to expand...
I first met this on motorcycle suspension. The ability to set both high-speed and low-speed damping (shaft speed) makes a huge difference to how a bike rides.
 
This thread is great!

And it's encouraging that in a universe where we're being told everyone should and is buying disposable Chinese EVs there is still a guerilla movement of people with the passion, property and panache to keep and run these old and new cars.

And then there are the communities that rise up around them.

And whilst the 'world is going to hell in a handcart' they are going to Southsea and Screwfix :rock:
 
 
Spotted this Neue Klasse BMW EV hot weather testing on the motorway in Abu Dhabi this afternoon.
We were in our BMW iX EV and drove alongside them - gave the engineers a wave and they smiled and waved back, which was a nice touch!
They certainly chose a good time for hot weather testing - it has been between 47 and 51 degrees C here for the past week!
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