Bigger Roll bars and uk roads
16 December 2014, 01:13 PM
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Bigger Roll bars and uk roads
Has anyone felt that there ride quality or road holding on bumpy roads has suffered due to fitting uprated roll bars?
The reason I ask is since fitting 24mm whiteline front and rear roll bars my car doesn't feel as planted on A roads when pushing on a bit.
It's perfectly fine on motorways ect. Just looses its composure on less than perfect roads.
Will be changing them in a week so will see if they are the culprit.
The reason I ask is since fitting 24mm whiteline front and rear roll bars my car doesn't feel as planted on A roads when pushing on a bit.
It's perfectly fine on motorways ect. Just looses its composure on less than perfect roads.
Will be changing them in a week so will see if they are the culprit.
17 December 2014, 03:10 PM
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I've recently removed my Whiteline AR bars and gone back to standard bars owing to other suspension changes which weren't working as they should have.
The badly choppy ride on the Whiteline bars has now improved quite a bit and it went to prove that the AR bar was adding significantly to the spring rate.
Consequently, I'm now wondering how much the AR bars were contributing to the harsh non compliant ride of my coilovers.
Still experimenting....
I'll be interested in your opinion after your change.
The badly choppy ride on the Whiteline bars has now improved quite a bit and it went to prove that the AR bar was adding significantly to the spring rate.
Consequently, I'm now wondering how much the AR bars were contributing to the harsh non compliant ride of my coilovers.
Still experimenting....
I'll be interested in your opinion after your change.
17 December 2014, 03:39 PM
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I've recently removed my Whiteline AR bars and gone back to standard bars owing to other suspension changes which weren't working as they should have.
The badly choppy ride on the Whiteline bars has now improved quite a bit and it went to prove that the AR bar was adding significantly to the spring rate.
Consequently, I'm now wondering how much the AR bars were contributing to the harsh non compliant ride of my coilovers.
Still experimenting....
I'll be interested in your opinion after your change.
The badly choppy ride on the Whiteline bars has now improved quite a bit and it went to prove that the AR bar was adding significantly to the spring rate.
Consequently, I'm now wondering how much the AR bars were contributing to the harsh non compliant ride of my coilovers.
Still experimenting....
I'll be interested in your opinion after your change.
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20 December 2014, 04:01 PM
#8
Really interesting question.
I've been pondering this. What is this fixation with big bars on an awd ROAD car?
I don't really know the answers, but I'll have a go.
Thinking out loud:
It's awd, so traction is very good. If you use a big bar you reduce the side-to-side independence of the suspension. So, a suspension movement on one side of the car, is transmitted to the other. Which reduces traction/grip/comfort!
You approach a corner entry, you've braked to too early/late, your entry speed's too fast: something. You turn-in, and the front washes wide, the more you turn and brake the worse it gets (I know you shouldn't).
So, why do we immediately go and get a bigger rear bar?
We go to the same corner, make the same mistake, the front starts to wash wide, but now the bigger rear bar is doing its job, and causing a decrease in rear grip - we're now going around the corner, with both ends washing wide?! But, the rear is trying to come 'round faster than the front - is that right? We're now going sideways, not forwards; that's not fast, fun, but not fast. We can't apply the throttle, yet, as at best, we've got 2 wheels up the kerb, on a grass verge or in a ditch.
Why don't we do tyre pressures, caster, camber first?
If it still washing wide at the front, why don't we go for just a larger front bar? To stop loss of camber at the front tyres, during turn-in? As the MacPherson strut front suspension is allowing loss of camber, and therefore a smaller tyre contact patch.
Shouldn't we all be using the smallest bars possible, that give us our preferred balance. And shouldn't they be the last thing we touch, not the first?
I've been pondering this. What is this fixation with big bars on an awd ROAD car?
I don't really know the answers, but I'll have a go.
Thinking out loud:
It's awd, so traction is very good. If you use a big bar you reduce the side-to-side independence of the suspension. So, a suspension movement on one side of the car, is transmitted to the other. Which reduces traction/grip/comfort!
You approach a corner entry, you've braked to too early/late, your entry speed's too fast: something. You turn-in, and the front washes wide, the more you turn and brake the worse it gets (I know you shouldn't).
So, why do we immediately go and get a bigger rear bar?
We go to the same corner, make the same mistake, the front starts to wash wide, but now the bigger rear bar is doing its job, and causing a decrease in rear grip - we're now going around the corner, with both ends washing wide?! But, the rear is trying to come 'round faster than the front - is that right? We're now going sideways, not forwards; that's not fast, fun, but not fast. We can't apply the throttle, yet, as at best, we've got 2 wheels up the kerb, on a grass verge or in a ditch.
Why don't we do tyre pressures, caster, camber first?
If it still washing wide at the front, why don't we go for just a larger front bar? To stop loss of camber at the front tyres, during turn-in? As the MacPherson strut front suspension is allowing loss of camber, and therefore a smaller tyre contact patch.
Shouldn't we all be using the smallest bars possible, that give us our preferred balance. And shouldn't they be the last thing we touch, not the first?
Last edited by 2pot; 20 December 2014 at 04:04 PM.
20 December 2014, 06:16 PM
#9
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Why don't we do tyre pressures, caster, camber first?
This is exactly what to do first , a good set of coilovers on Prodrive tarmac angles to start with , 30mm lower , better brakes , powerflex on the bushings and then some decent new rubber, Once you have that sorted , I might be tempted to do something on thicker roll bars , but more than likely only if I were into track days.
This is exactly what to do first , a good set of coilovers on Prodrive tarmac angles to start with , 30mm lower , better brakes , powerflex on the bushings and then some decent new rubber, Once you have that sorted , I might be tempted to do something on thicker roll bars , but more than likely only if I were into track days.
21 December 2014, 03:29 PM
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This is really interesting! I've recently purchased a standard classic Turbo 2000 & the 15-year old suspension appears to be in good order although the rear anti-roll bar is corroded & the rear drop links were replaced for the last MoT. The advice I'm getting is "Whiteline rear anti-roll bar, aluminium front & rear drop links,Whiteline front strut mount." Reading this thread I'm not so sure that is the way to go with a classic! 😐
21 December 2014, 04:08 PM
#12
Has anyone felt that there ride quality or road holding on bumpy roads has suffered due to fitting uprated roll bars?
The reason I ask is since fitting 24mm whiteline front and rear roll bars my car doesn't feel as planted on A roads when pushing on a bit.
It's perfectly fine on motorways ect. Just looses its composure on less than perfect roads.
Will be changing them in a week so will see if they are the culprit.
The reason I ask is since fitting 24mm whiteline front and rear roll bars my car doesn't feel as planted on A roads when pushing on a bit.
It's perfectly fine on motorways ect. Just looses its composure on less than perfect roads.
Will be changing them in a week so will see if they are the culprit.
What suspension system do you have now? Fixed perch/coilover? What type etc?
Is your car lowered?
What dia wheels, and what tyres?
What power is your car running?
What alignment settings have you dialled into the car?
ARB's should not, on their own make for a more or less compliant ride - there are just too many other variables involved
24 December 2014, 01:28 PM
#14
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I run BC's not approved TÜV but IMHO safer than std. In summer I took my 2 kids and my 86 year mother and the luggage to go on holiday and the re-action from the back seat was , "Thanks dad now we don't get sick." But I am spoiled here as even a country lane is better surfaced than best of the UK A roads. It never ceases to amaze me how road councils in the UK fail to get this organised , as Britain (south anyhow ) really isn't that large and certainly does not have the freeze-thaw activity we have in Germany.
Your point on the Urethane is a good one and I agree , that's why Id use powerflex ( its a mix with silcon rubber compound) on any pivot.
24 December 2014, 05:51 PM
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I recently fitted a bigger (22mm - middle setting) whiteline arb to my 99 uk wagon and I think it's a huge improvement. I'm still on stock suspension.
I don't think the ride has been compromised. But, the car now has a clunk coming from somewhere in the rear but I can't work where from.....
I don't think the ride has been compromised. But, the car now has a clunk coming from somewhere in the rear but I can't work where from.....
24 December 2014, 10:36 PM
#16
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I recently fitted a bigger (22mm - middle setting) whiteline arb to my 99 uk wagon and I think it's a huge improvement. I'm still on stock suspension.
I don't think the ride has been compromised. But, the car now has a clunk coming from somewhere in the rear but I can't work where from.....
I don't think the ride has been compromised. But, the car now has a clunk coming from somewhere in the rear but I can't work where from.....
So took them out , rather than replace again.
27 December 2014, 08:59 AM
#17
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Well I finally had both my roll bars replaced on Tuesday. I did a straight swap from 24mm front and rear, to 22mm front and rear.
I've done a fair few miles since then and the car is more compliant over uneven roads and does handle bumps better. But still not where I want the car to be in terms of control while on our A/b roads.
I've not noticed any increase in roll either. Maybe it's not pushed hard enough on the road to see the benefit of having a larger bar.
I've also been able to increase my dampers two clicks this before would of made the car to nervous on a less than perfect A or B road.
Although this has been an improvement I still think think there is more to be done. might try fitting the original front bar at some point to see if that helps things further.
I've done a fair few miles since then and the car is more compliant over uneven roads and does handle bumps better. But still not where I want the car to be in terms of control while on our A/b roads.
I've not noticed any increase in roll either. Maybe it's not pushed hard enough on the road to see the benefit of having a larger bar.
I've also been able to increase my dampers two clicks this before would of made the car to nervous on a less than perfect A or B road.
Although this has been an improvement I still think think there is more to be done. might try fitting the original front bar at some point to see if that helps things further.
Last edited by InTurbo; 27 December 2014 at 10:40 AM.
27 December 2014, 09:51 AM
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Would need to know something of your set-up to begin to focus on an answer....
What suspension system do you have now? Fixed perch/coilover? What type etc?
Is your car lowered?
What dia wheels, and what tyres?
What power is your car running?
What alignment settings have you dialled into the car?
ARB's should not, on their own make for a more or less compliant ride - there are just too many other variables involved
What suspension system do you have now? Fixed perch/coilover? What type etc?
Is your car lowered?
What dia wheels, and what tyres?
What power is your car running?
What alignment settings have you dialled into the car?
ARB's should not, on their own make for a more or less compliant ride - there are just too many other variables involved
The cars on Bc type ra coilovers with adjustable top mounts and rubber rear mounts
The ride height centre of wheel to arch is 360mm front 350mm rear
Think this maybe a bit low!
Car now has 22mm front and rear bars rear is set to middle
Anti lift kit also fitted
Wheels are 17'' oem Sti
Tyres are Goodyear eagle F1 asymmetric 2's
Front camber is 1.15
Front toe 0.03
Rear camber is 1.30
Rear toe 0.06
Power is circa 375 bhp 440 ft lbs
27 December 2014, 11:07 AM
#19
Well first off, your set-up has a good few positives
Ride height looks fine, which always can be a big stumbling block. Nothing worse than an over-lowered scooby
Geo settings look spot on
As for the rolls bars, I have always settled on 24 rear, set to middle setting and 22mm front on firm. This for both the classic and new age (up to Hatch).
You have a little extra compliancey in 17" dia wheels (the best size IMO), and the F1 tyres which have a medium/soft side wall
You can 'see how it goes' with what you have now, or, for the time it takes, swap out the rear bar again for the 24 to see how you like that
But all in all, I think you shouldn't be too far away now. When you say you think there's more that can be done, what aspects of the car's handling do you think is lacking?
Ride height looks fine, which always can be a big stumbling block. Nothing worse than an over-lowered scooby
Geo settings look spot on
As for the rolls bars, I have always settled on 24 rear, set to middle setting and 22mm front on firm. This for both the classic and new age (up to Hatch).
You have a little extra compliancey in 17" dia wheels (the best size IMO), and the F1 tyres which have a medium/soft side wall
You can 'see how it goes' with what you have now, or, for the time it takes, swap out the rear bar again for the 24 to see how you like that
But all in all, I think you shouldn't be too far away now. When you say you think there's more that can be done, what aspects of the car's handling do you think is lacking?
27 December 2014, 11:28 AM
#20
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Well first off, your set-up has a good few positives
Ride height looks fine, which always can be a big stumbling block. Nothing worse than an over-lowered scooby
Geo settings look spot on
As for the rolls bars, I have always settled on 24 rear, set to middle setting and 22mm front on firm. This for both the classic and new age (up to Hatch).
You have a little extra compliancey in 17" dia wheels (the best size IMO), and the F1 tyres which have a medium/soft side wall
You can 'see how it goes' with what you have now, or, for the time it takes, swap out the rear bar again for the 24 to see how you like that
But all in all, I think you shouldn't be too far away now. When you say you think there's more that can be done, what aspects of the car's handling do you think is lacking?
Ride height looks fine, which always can be a big stumbling block. Nothing worse than an over-lowered scooby
Geo settings look spot on
As for the rolls bars, I have always settled on 24 rear, set to middle setting and 22mm front on firm. This for both the classic and new age (up to Hatch).
You have a little extra compliancey in 17" dia wheels (the best size IMO), and the F1 tyres which have a medium/soft side wall
You can 'see how it goes' with what you have now, or, for the time it takes, swap out the rear bar again for the 24 to see how you like that
But all in all, I think you shouldn't be too far away now. When you say you think there's more that can be done, what aspects of the car's handling do you think is lacking?
Also tried a few tyre different tyre pressures currently running 36 front 34 rear powerstations recommendations
I was also thinking of increasing the ride height. Both front a rear control arms look parallel to the floor.
27 December 2014, 05:09 PM
#21
What you're describing there is normally down to insufficient damper/spring travel, bump steer, or over-lowering (in the main)
360/350 should be fine, but you say your control arms are horizontal??
Do you have a pic of your car - preferably side on, but not crucial?
360/350 should be fine, but you say your control arms are horizontal??
Do you have a pic of your car - preferably side on, but not crucial?
27 December 2014, 06:12 PM
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Maybe the spring is set too low on the strut body causing a lack of damper travel
Don't have a pic with the coilovers fitted. Might take a pic tomorrow and one of the strut
Last edited by InTurbo; 27 December 2014 at 06:21 PM.
27 December 2014, 07:32 PM
#24
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Um not much. Just that the alignment is ok and that I should lower it more.
And what I need is some Ast Coilovers.
I did mention about the control arms being horizontal but they have never had any problems with the arms being like that. Also asked about roll centre and they had no idea what I was on about.
And what I need is some Ast Coilovers.
I did mention about the control arms being horizontal but they have never had any problems with the arms being like that. Also asked about roll centre and they had no idea what I was on about.
Last edited by InTurbo; 27 December 2014 at 07:39 PM.
27 December 2014, 07:50 PM
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what would be the ideal ride height for a Sti with out roll centre correction.
