What mods are recommended for the anti roll bars on a HF1600 S2 ?
The car is intended for road rally use no necessarily racing
Cheers
Michael
Anti roll bars
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william
Re: Anti roll bars
Flavia 2000 18mm roll bar. Slightly stiffer means slightly less roll. Straight fit when you have the flavia rubbers.
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P. de R. Leclercq
Re: Anti roll bars
Yes, a very good mod. In fact it can be squeezed into the Fulvia rubbers if they are slightly "used" and tightens everything up nicely.
For the rear - which is most necessary with decent tyres - there is no easy solution except to have one made. It is easy to make being a simple shape, I have a 5/8" (16mm) bar which was cold bent from EN16T - please don't ask me the Euro equivalent of this but it's a common high-grade steel ideal for this application.
Paul
For the rear - which is most necessary with decent tyres - there is no easy solution except to have one made. It is easy to make being a simple shape, I have a 5/8" (16mm) bar which was cold bent from EN16T - please don't ask me the Euro equivalent of this but it's a common high-grade steel ideal for this application.
Paul
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william
Re: Anti roll bars
Paul,
You have fitted a thicker rear bar. From 14 to 16mm. If I'm correct this introduces more understeer. The works have removed the rear stabilizer bar in some cars like munaris nr 14. What was your reason to do this?
You have fitted a thicker rear bar. From 14 to 16mm. If I'm correct this introduces more understeer. The works have removed the rear stabilizer bar in some cars like munaris nr 14. What was your reason to do this?
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P. de R. Leclercq
Re: Anti roll bars
Hello William.
Yes, the rear bar is about 60% stiffer than the original.
You are not correct about the effect though: a stiffer rear bar TENDS (important word this) to make the car oversteer, becaause weight transfer is reduced.
The reason for my fitting the bar was because I could feel the car rolling more at the rear than at the front. I had stiffened the rear springs (extra inverted leaf) but still had the problem.
As the car has a stiffened shell I did not want understeer induced by "skewed roll" coming out of corners on track days. The car is better with the stiffer rear bar, and as I say stiffer bars are probably necessary with today's tyres.
I would add though, that this all really only applies to modified cars that are used for track events and perhaps tarmac rallies. I do not think that these mods are absolutley necessary for normal touring use on the road.
As I have said before, all cars are compromises; in modifying a car one tries to find the compromise that suits one's needs the best.
Paul
Yes, the rear bar is about 60% stiffer than the original.
You are not correct about the effect though: a stiffer rear bar TENDS (important word this) to make the car oversteer, becaause weight transfer is reduced.
The reason for my fitting the bar was because I could feel the car rolling more at the rear than at the front. I had stiffened the rear springs (extra inverted leaf) but still had the problem.
As the car has a stiffened shell I did not want understeer induced by "skewed roll" coming out of corners on track days. The car is better with the stiffer rear bar, and as I say stiffer bars are probably necessary with today's tyres.
I would add though, that this all really only applies to modified cars that are used for track events and perhaps tarmac rallies. I do not think that these mods are absolutley necessary for normal touring use on the road.
As I have said before, all cars are compromises; in modifying a car one tries to find the compromise that suits one's needs the best.
Paul
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Michael Beattie
Re: Anti roll bars
Thanks Paul and William,
Having only done one short but twisty hillclimb, I noticed that the car had a lot of roll and was unloading the inside front, which then started to spin and hence a loss of traction.
I'll see about up-rating both bars to flatten the cornering attitude. I must admit my understanding of front wheel drive cars was to stiffen the rear bar (usually with a touch of +ive camber) to provoke a small amount of oversteer and help kill the normal understeer to give a more neutral cornering attidude.
Is there any way of adjusting the rear camber on a S2 axle?
However, I must keep reminding myself that this car is not intended for hillclimb / sprint usage as it's primary aim, but more on road navigation rallies, so changing the bars is probably all I need to do.
Are there any decent sources within the UK for these parts?
Cheers
Michael
Having only done one short but twisty hillclimb, I noticed that the car had a lot of roll and was unloading the inside front, which then started to spin and hence a loss of traction.
I'll see about up-rating both bars to flatten the cornering attitude. I must admit my understanding of front wheel drive cars was to stiffen the rear bar (usually with a touch of +ive camber) to provoke a small amount of oversteer and help kill the normal understeer to give a more neutral cornering attidude.
Is there any way of adjusting the rear camber on a S2 axle?
However, I must keep reminding myself that this car is not intended for hillclimb / sprint usage as it's primary aim, but more on road navigation rallies, so changing the bars is probably all I need to do.
Are there any decent sources within the UK for these parts?
Cheers
Michael
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P. de R. Leclercq
Re: Anti roll bars
I found that fitting the 2000 front bar improved turn in greatly - and might even have reduced understeer!
I am quite convinced that the thicker rear bar was a great improvement.
Stiffening the rear springs is good especially if the car is powerful, since reducing front/rear weight transfer will help a little to reduce wheelspin.
There is no practical way of changing the rear camber. For myself I would have liked to have been able to play with the rear toe-in, trading off directional stability for improved directional changes. However I found that setting the front to parallel or even a little toe-in made the steering very sharp and the back was happy to follow although one had to be awake on a track day with cold rear tyres...
Leda will make bars to order; there is another firm in Surrey but I have forgotten the name. They can cold bend bar up to 29mm I think!
Paul
I am quite convinced that the thicker rear bar was a great improvement.
Stiffening the rear springs is good especially if the car is powerful, since reducing front/rear weight transfer will help a little to reduce wheelspin.
There is no practical way of changing the rear camber. For myself I would have liked to have been able to play with the rear toe-in, trading off directional stability for improved directional changes. However I found that setting the front to parallel or even a little toe-in made the steering very sharp and the back was happy to follow although one had to be awake on a track day with cold rear tyres...
Leda will make bars to order; there is another firm in Surrey but I have forgotten the name. They can cold bend bar up to 29mm I think!
Paul
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william vd Sman
Re: Anti roll bars
nobody tried a thicker front bar than the 18mm Flavia? 18mm is not very thick by todays standards. I think Alfas especially GTA's used very fat bars.
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Michael Beattie
Re: Anti roll bars
William
Part of the reason the Alfas have thick front a/r bars, is to try and counteract the rear suspension geometry, which suffers from a high roll centre due to the T-bar that centralises the back axle. They use soft springs on the rear to try and help redice the oversteer, usually removing the rear a/r bar altogether, and put in thicker front bars. An Alfa uses something like a 180 lb rear spring and a 850 lb or higher front !! ( I have just sold a comp prepared 67 Sprint GT, hence the inside info !!)
Certainly, I agree with Paul that a stiffer rear bar on a Lancia should do the trick. If you look at most modern front drive competition cars you will usually see them lifting an inside rear wheel under hard cornering, as the rear roll is often set to "full stiff" in an effort to create some oversteer and kill the natural FWD understeer. The front ends are usually a lot "softer" in roll.
However, Fulvias have always been complimented on their good handling, which is why I asked what the Forum thought about a/r bars, as they may not necessarily follow that trend.
Has anyone tried tethering / tying up the rear suspension to limit the amount of droop ?
Cheers
Michael
Part of the reason the Alfas have thick front a/r bars, is to try and counteract the rear suspension geometry, which suffers from a high roll centre due to the T-bar that centralises the back axle. They use soft springs on the rear to try and help redice the oversteer, usually removing the rear a/r bar altogether, and put in thicker front bars. An Alfa uses something like a 180 lb rear spring and a 850 lb or higher front !! ( I have just sold a comp prepared 67 Sprint GT, hence the inside info !!)
Certainly, I agree with Paul that a stiffer rear bar on a Lancia should do the trick. If you look at most modern front drive competition cars you will usually see them lifting an inside rear wheel under hard cornering, as the rear roll is often set to "full stiff" in an effort to create some oversteer and kill the natural FWD understeer. The front ends are usually a lot "softer" in roll.
However, Fulvias have always been complimented on their good handling, which is why I asked what the Forum thought about a/r bars, as they may not necessarily follow that trend.
Has anyone tried tethering / tying up the rear suspension to limit the amount of droop ?
Cheers
Michael
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P. de R. Leclercq
Re: Anti roll bars
Hold on a minute William!
Yes anti-roll bars come in all sorts of sizes on all types of vehicle. That doesn't mean that big is good on a particular car.
The 18mm bar is about 60% stiffer than the 16mm one. Probably enough unless perhaps you were running slicks and getting them properly warmed up.
Paul
Yes anti-roll bars come in all sorts of sizes on all types of vehicle. That doesn't mean that big is good on a particular car.
The 18mm bar is about 60% stiffer than the 16mm one. Probably enough unless perhaps you were running slicks and getting them properly warmed up.
Paul