Discussion
Many people run them? Im current on lowering springs but tempted to go for coilovers to reduce ride height slightly and have more control over damping etc.
The main reason i want them is i have been told that stiffening the rear coilovers can help with fwd traction as the weight shift is less, first of all does this help in practice? And second of all what effects on handling will it have? Im guessing it will more easily oversteer?
The main reason i want them is i have been told that stiffening the rear coilovers can help with fwd traction as the weight shift is less, first of all does this help in practice? And second of all what effects on handling will it have? Im guessing it will more easily oversteer?
Suspension tuning is a bit of a dark art. You're balancing a number of things and just making one end harder will almost certainly have negative effects.
There are probably a few sets of published settings for your car online for the various suspension manufacturers, that when used together produce decent results. Check owner specific forums for these - I've certainly seen them in the past.
Basically, the harder you go, the more likely the car will struggle with road surface imperfections and be likely to skip, rather than track the surface of the road. Obviously this means the tyres are in contact with tarmac for less time. Also, going harder affects passenger comfort, as I'm sure you know.
Done properly, however, you may be able to sacrifice a small amount of comfort for big handling improvements... If you get it right.
Worth noting that the best handling cars are often not the hardest in terms of suspension. Told you it was a dark art!
Another thing to note is that the first suspension component is the tyre. If you want to firm things up, could you drop a bit of sidewall by going to a bigger rim with a lower profile tyre?
There are probably a few sets of published settings for your car online for the various suspension manufacturers, that when used together produce decent results. Check owner specific forums for these - I've certainly seen them in the past.
Basically, the harder you go, the more likely the car will struggle with road surface imperfections and be likely to skip, rather than track the surface of the road. Obviously this means the tyres are in contact with tarmac for less time. Also, going harder affects passenger comfort, as I'm sure you know.
Done properly, however, you may be able to sacrifice a small amount of comfort for big handling improvements... If you get it right.
Worth noting that the best handling cars are often not the hardest in terms of suspension. Told you it was a dark art!
Another thing to note is that the first suspension component is the tyre. If you want to firm things up, could you drop a bit of sidewall by going to a bigger rim with a lower profile tyre?
Just for clarity, you're taking about removing the springs from a car with a seprate spring and damper setup and replacing the damper unit with an after-market one-piece coil-over-damper? That replacement will, in itself, make negligable difference to how the car drives. It just tends to be a convenient way of replacing the springs and dampers at the same time to a matched pair of aftermarket components.
In terms of how you set up a FWD, as above it's something of a dark art but at a high level: All FWD cars are stiffer in roll at the rear than at the fornt, for the reasons you mention; this is why they tend to cock a rear wheel under heavy cornering. If you stiffen the rear further relative to the front you will probably improve traction on corner exit but will make the rear-end less progressive as it loses grip - ie if the rear lets go, it'll be far more sudden. You'll also reduce ultimate rear-end grip a bit, especially on bumpy surfaces.
Overall the biggest improvements in feel and grip will probably come from improving the quality of the dampers rather than changing their ultimate damping rate. Higher quality (which usually means bigger bore) dampers will be less "sticky" which means they allow the suspension to respond much faster, especially to small bumps, whilst still effectively damping out the movement which both increases grip and improves secondary ride qualtiy. Obviously if you have higher quality dampers, you can also afford to stiffen the springs a bit without making the secondary ride unbarable, although the stiffer springs will still impact the primary ride. However, really good dampers are expensive.
OEM dampers aren't generally great on mainstream cars but neither are they terrible; cheap "coilover" kits will probably be worse. To improve upon OEM quality on a mainstream car you'll probably be spending 4 figures for a full set of coil-over-dampers. Really good damper units can cost that much each.
Personally I wouldn't mess with the front/rear balance myself. Depending on what the car is, there may be well thought out and tested aftermarket kits which change the balance slightly in the way you want.
ETA: For a good balance of road holding and comfort, it might be worth seeing if anyone makes a well-regarded kit with rising rate springs for your car. They allow the initial spring travel to be relatively soft to absorb bumps but stiffen up as significant compression is applied to keep body-roll in check. They are, however, far harder (arguably impossible) to set up properly.
In terms of how you set up a FWD, as above it's something of a dark art but at a high level: All FWD cars are stiffer in roll at the rear than at the fornt, for the reasons you mention; this is why they tend to cock a rear wheel under heavy cornering. If you stiffen the rear further relative to the front you will probably improve traction on corner exit but will make the rear-end less progressive as it loses grip - ie if the rear lets go, it'll be far more sudden. You'll also reduce ultimate rear-end grip a bit, especially on bumpy surfaces.
Overall the biggest improvements in feel and grip will probably come from improving the quality of the dampers rather than changing their ultimate damping rate. Higher quality (which usually means bigger bore) dampers will be less "sticky" which means they allow the suspension to respond much faster, especially to small bumps, whilst still effectively damping out the movement which both increases grip and improves secondary ride qualtiy. Obviously if you have higher quality dampers, you can also afford to stiffen the springs a bit without making the secondary ride unbarable, although the stiffer springs will still impact the primary ride. However, really good dampers are expensive.
OEM dampers aren't generally great on mainstream cars but neither are they terrible; cheap "coilover" kits will probably be worse. To improve upon OEM quality on a mainstream car you'll probably be spending 4 figures for a full set of coil-over-dampers. Really good damper units can cost that much each.
Personally I wouldn't mess with the front/rear balance myself. Depending on what the car is, there may be well thought out and tested aftermarket kits which change the balance slightly in the way you want.
ETA: For a good balance of road holding and comfort, it might be worth seeing if anyone makes a well-regarded kit with rising rate springs for your car. They allow the initial spring travel to be relatively soft to absorb bumps but stiffen up as significant compression is applied to keep body-roll in check. They are, however, far harder (arguably impossible) to set up properly.
Edited by kambites on Thursday 30th April 09:30
I usually find coilovers are better than just lowering springs, especially if your shocks are old and have seen better days. Also, Coilovers, as you say have more adjustability. What car is it? I have good experiences with Meister R Coilovers, they don't cost the earth, but have a very good reputation and great customer service, I have had them on 2 cars and have no complaints. The key is to get coilovers set up properly, don't just take them to your local Kwik Fit :-)
mnaylor said:
Coilovers, as you say have more adjustability.
That's not necessarily a given. Many after-market coilover-damper kits have adjustable spring platforms and some have 1, 2 or even 3 way adjustable damping, but equally some have no adjustment at all. Personally I'd avoid adjustable damping, especially more than 1-way adjustable damping, unless you really know what you're doing. Even adjustable ride height you really need corner-weight scales to get the most out of (unless, as you say, you pay someone else to set them up for you).
Edited by kambites on Thursday 30th April 09:41
You don't say what the car is?
In the past I ran a Mk2 Focus ST, first with lowering springs, then with lowering springs and matched dampers from Bilstein then latterly coilovers, a lot depends on your use with the car, i.e is it a daily driver? Weekend car? Track use? etc
For a daily car with no track use I would suggest a set of good lowering springs with matched dampers from Bilstein to be a good overall compromise
In the past I ran a Mk2 Focus ST, first with lowering springs, then with lowering springs and matched dampers from Bilstein then latterly coilovers, a lot depends on your use with the car, i.e is it a daily driver? Weekend car? Track use? etc
For a daily car with no track use I would suggest a set of good lowering springs with matched dampers from Bilstein to be a good overall compromise
I don't see any material advantage in handling. How could there be, you're just replacing the dampers and springs.
Where they have a HUGE advantage is being able to alter the ride height by a few mm (or even lots of mm) if circumstance change, or you decide that lowering the car 30 mm wasn't such a great idea after all and you really fancy 20 mm.
Where they have a HUGE advantage is being able to alter the ride height by a few mm (or even lots of mm) if circumstance change, or you decide that lowering the car 30 mm wasn't such a great idea after all and you really fancy 20 mm.
Fiesta ST If I recall correctly? Think the OP has made a few posts now about how to improve traction on it.
Tyres > bit of right foot training > LSD for me I think. Coilovers (a good set) can help run adjustable rideheights whilst still retaining optimum damping for the spring rates. I think to have a tangible improvement to traction from damper settings alone you would need to compromise too much in other areas.
Tyres > bit of right foot training > LSD for me I think. Coilovers (a good set) can help run adjustable rideheights whilst still retaining optimum damping for the spring rates. I think to have a tangible improvement to traction from damper settings alone you would need to compromise too much in other areas.
It's worth noting that lowering a FWD car with Macpherson struts might actually reduce traction because you'll be increasing static camber.
A significant modification to the ride height (on any car) also risks messing up the intended dynamic toe adjustment (bump steer) which can make a mess of ths steering kinematics. If you're going to lower a car much, you should really raise the steering rack to compensate, and depending on the clearance around the steering components that's not always possible.
A significant modification to the ride height (on any car) also risks messing up the intended dynamic toe adjustment (bump steer) which can make a mess of ths steering kinematics. If you're going to lower a car much, you should really raise the steering rack to compensate, and depending on the clearance around the steering components that's not always possible.
Edited by kambites on Thursday 30th April 11:28
This is an old debate really;
90% of people who say coilovers are better generally go from worn out OE shocks with lowering springs to brand new coilovers so in that respect they will be "better" (as suddenly they have a car again that doesn't have f@#ked suspension)
However, in reality a good set of lowering springs with good lowered shocks (e.g. Bilsten B8s) will handle every bit as quality coilovers (costing £500+) and vastly better than the crap cheap coilovers at circa £200.
And all this without the pfaff of having to adjust them!
Of course there are exceptions, like when you start spend mega money - i.e. for those of you with "expensive" or track cars - but for your average joe modifier, with a typical hot hatch the above is always the case....the extra expense of coilovers isn't worth it.
90% of people who say coilovers are better generally go from worn out OE shocks with lowering springs to brand new coilovers so in that respect they will be "better" (as suddenly they have a car again that doesn't have f@#ked suspension)
However, in reality a good set of lowering springs with good lowered shocks (e.g. Bilsten B8s) will handle every bit as quality coilovers (costing £500+) and vastly better than the crap cheap coilovers at circa £200.
And all this without the pfaff of having to adjust them!
Of course there are exceptions, like when you start spend mega money - i.e. for those of you with "expensive" or track cars - but for your average joe modifier, with a typical hot hatch the above is always the case....the extra expense of coilovers isn't worth it.
That's a good point. Things like dampers and bushes may last 100k miles before they're bad enough to fail an MoT, but they tend to be past their best by about 50k miles. It's amazing how much difference a new set of OEM dampers and bushes can make to how a car drives, especially when combined with resetting the static geometry (although that's probably only toe on nost hot hatches?).
Fonzey said:
Tyres > bit of right foot training > LSD for me I think..
+1 buying a fresh / stickier / higher quality set of tyres will probably produce the biggest improvement in traction.Also from experience of coilovers would echo what kambites says about damper quality. You may find that none of the available coilovers for a Fiesta are sufficiently expensive to be an improvement on stock parts, especially as I believe Ford tend to spec relatively good dampers.
I'm dubious about the improvement in straight-line traction from stiffening the rear, I know it will reduce the pitch movement but can't see that making much difference to the weight over the front tyres. On corner exit, as has been said, higher rear roll stiffness will help keep the front tyres gripping - this is probably cheaper/easier achieved by fitting a rear anti-roll bar than coilovers.
I'd be concerned that fitting coilovers, you'll end up stiffer at the front as well, which will actually reduce traction as the wheels won't follow the bumps as well. Even the softest setting of coilovers you've still got the same spring rate which is likely much stiffer than stock.
Of course, the most effective way to improve traction would be to sell your Fiesta and buy a Scooby ;-)
rxe said:
I don't see any material advantage in handling. How could there be, you're just replacing the dampers and springs. .
Sring rates and damping characteristics are intrinsically important in determining the overal handling characteristics of a car. Damping can be split into two broad circuitts; compression (the speed at which the unit compresses) and rebound (the speed at which the unit returns to its pre-compressed state). The fine-tuning of these two circuits allows the tyres to remain in as best ocntact with the road as possible, and influence the balance of the car (both static and dynamically). Furthermore, it allows for fine-tuning of the feedback a driver gets. Given you can independantly fine-tune each corner of the car, you can have differant damping rates for compression and rebound all round - not just front to rear, but left to right also. I had a caterham, so one of the most adjustable cars money can buy.
My learnings are ‘don’t mess with what you don’t fully understand’.
The thing about chassis set ups is that it’s all physics - what you do here, changes things there, there and there. Oh, and there.
You can’t avoid it, the laws of physics are called laws for a reason. People dedicate their whole careers to this topic and are learning new things at 4pm on the day they retire.
My advice is pay a specialist you trust and be clear what you’re aiming for.
My learnings are ‘don’t mess with what you don’t fully understand’.
The thing about chassis set ups is that it’s all physics - what you do here, changes things there, there and there. Oh, and there.
You can’t avoid it, the laws of physics are called laws for a reason. People dedicate their whole careers to this topic and are learning new things at 4pm on the day they retire.
My advice is pay a specialist you trust and be clear what you’re aiming for.
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