Suspension setups question

[S18 RSG 429]

After buying the Tein coilovers as everyone suggested, as well as sorting out alignment (2deg negative camber front, 1.8deg rear) and getting the dampers tuned to a nice balanced setting (fairly stiff, but still forgiving over bumps) I'm now trying to find the best way to dial out some of the body roll present in the car. I feel like the car grips very well, and the tyres are able to stick to the road when required, however the sensation of cornering is still fairly exaggerated with the body roll. 

I don't particularly want to stiffen the dampers any more (certainly not for road use anyway) as the ride suffers far more than I gain. What would you guys suggest as the next step?

I see there are plenty of options out there, anti roll bars, chassis stiffening kits, body braces and all sorts, but I've read good and bad about most of the options, especially anti roll bars and them being too stiff and causing a loss of traction.

Anyone had any good experiences with any particular products that they would recommend?

[Deacon 1357]

I've got the whiteline adjustable front and rear arb's on mine and have been very happy with them.

I've also got a front and rear strut brace and the trd door braces to help stiffen the chassis. A number of the stock bushes have also been uprated.

[Church 209]

That roll won't affect much actual cornering speeds/grip. Maybe what it does most, affects your confidence to push more

If you track not just day or two per year .. i would deal in more neg camber and maybe stiffen a bit. Though still, while Tein A/Z are better then stock, and even on slight tracking more capable then them, even more so at their price range, they imho are not made for strictly track-purpose, rather some interim compromise solution (closer to street/comfort at that), and you may simply start to outgrow them/reach their limits, especially if on stickier tyres.

[S18 RSG 429]

I'm not on particularly sticky tyres @Church, and your assumption is correct that it will only be the occasional track day, however, living where I live means I'm driving on twisty B roads every day, and when quiet, I like to drive it hard. Having so much roll is exactly as you say, not very confidence inspiring, and given that roll stiffness and ride stiffness are two different entities, I know I can up the roll stiffness without affecting ride quality too much, which I don't want to do. 

Another factor, is that while the roads around here are great, the quality of the tarmac is less so, so I really need some forgiveness in the springs, which I currently have after a few months of tweaking here and there. 

My main goal here is to keep the car very daily-able (soft and compliant over bumps as it currently is), but rigid enough that it remains level under hard cornering. I know it can be achieved, I just want to know the best way.

Thanks for the advice @Deacon, anti roll bars would seem like the most obvious way to reduce roll (clue being in the title and all that), just worried about over-stiffening in this department. Last thing I want is to overstiffen and cause the inside wheel to start lifting under heavy cornering. That's fun in FWD, not so much in RWD.

[Deacon 1357]

8 minutes ago, S18 RSG said:

@Church

Thanks for the advice @Deacon, anti roll bars would seem like the most obvious way to reduce roll (clue being in the title and all that), just worried about over-stiffening in this department. Last thing I want is to overstiffen and cause the inside wheel to start lifting under heavy cornering. That's fun in FWD, not so much in RWD.

I have flung mine into corners at Curborough far faster than you could ever do on the public road and never lifted a wheel so I don't think that'll be an issue mate.

[S18 RSG 429]

Just now, Deacon said:

I have flung mine into corners at Curborough far faster than you could ever do on the public road and never lifted a wheel so I don't think that'll be an issue mate.

What thickness ARBs are you running? I was reading a thread on here earlier today that talked about someone who had done some testing with ARBs and found the thicker ones to be too stiff, and to be lifting the inside wheel and losing traction :/

[Deacon 1357]

I've got the whiteline front and rear adjustable bars. I run the front at the softest of the two settings and the rear at the stiffest of the three settings (or at least did while I was on the Tein Flex A's). From memory I think it's a 20mm front, 16mm rear. I've had them on for the last year and never had an issue on road or track.

[S18 RSG 429]

Ah ok, that does make sense then. I've read everywhere that 16mm rear is ideal. I think the testing was done on some 20-24mm rear ARBs, and they were causing the issues with over-stiffness.

Perhaps that's the best place to start looking then. Cheers Jeff.

Also, happy 1000th post.

[Deacon 1357]

13 minutes ago, S18 RSG said:

Ah ok, that does make sense then. I've read everywhere that 16mm rear is ideal. I think the testing was done on some 20-24mm rear ARBs, and they were causing the issues with over-stiffness.

Perhaps that's the best place to start looking then. Cheers Jeff.

Also, happy 1000th post.

Lol! Hadn't noticed that!

One thing to bear in mind on the sizes is that the solid bars will be thinner than the hollow ones but the roll stiffness will be the same.

[Bles 32]

Hi was just wondering if you had considered the edfc pro as find mine has very limited body roll with this fitted.

[S18 RSG 429]

I was under the impression that all the EDFC pro does is allow you to change the damper settings from within the cabin? If that's the case, it's not really achieving much more than me just getting out and changing them by hand, unless I'm wrong in my assumption of course.

[Ade 517]

How much are you lowered over stock?

Regarding roll bars, you might be talking about Stu who did some testing of different roll bars but that was stock GT86 suspension. The ideal bar(s) will depend on the suspension setup. With even spring rates, I would stick to the front 20mm and rear 16mm adjustable whiteline bars set to full soft. This adds roughly proportional roll stiffness front to back so shouldn't affect balance too much but will give less roll which is the goal.

 

 

[S18 RSG 429]

I'm only lowered around 30mm over stock @Ade.

I believe it was Stu's blog I saw being discussed. I didn't see too much detail, just that he found over stiffening caused him to lose traction, which I wanted to avoid.

As for spring rates, I'm running 7kg/mm front and back, so I think your suggestion sounds good.

[Lauren 2259]

7 hours ago, S18 RSG said:

I was under the impression that all the EDFC pro does is allow you to change the damper settings from within the cabin? If that's the case, it's not really achieving much more than me just getting out and changing them by hand, unless I'm wrong in my assumption of course.

It allows the damper rate to vary according to the G-force levels, so it increases the damper rate as you corner, brake and accellerate. It is programmable, so I find that the increase in damper rate helps when I corner, which is what the EDFC Active Pro is for. I've never changed my anti-roll bars, you want some suspension movement to allow it to work, particularly so on the road. Increasing the size of the ARB's will increase the spring rate effectively under load. On bumpy roads, this will increase the chances of traction problems. 

A 7/7kg spring rate I think is high for UK roads. Most run 6/6kg with the Tein Flex. I use 5/6kg.

[Church 209]

Thicker rollbars = less independent suspension / less grip / and yes, less roll. But first two, while may add a bit to handling confidence, actually can reduce cornering capabilities. Somehow almost forgot about EDFC possibility even though you mentioned Teins in OP. Imho yes, EDFC should give best of both worlds, both keep comfort on bad roads & reduce roll (dive & squat at accel/braking too). Not cheap option though.

[Deacon 1357]

@S18 RSG which teins are you on out of curiosity?

[S18 RSG 429]

Street Advance I believe @Deacon. I mentioned some time ago that I initially got the Street Advances after the garage destroyed my stock dampers as I couldn't get the Flex's on a short delivery time. I then tried some Flex Z's for a short while when they were back in stock as they seemed to be what most people were running, but aside from the slightly better ride over rough ground (which I assume was thanks to the HBS) I didn't find them noticably better than the Street Advances, so sent the Flex's back and stuck with the cheaper option.

[Deacon 1357]

Ah ok - it was the spring rate that confused me. The street advances are 5kg front and rear - were yours a revalved special order?

The flex z's don't have the hbs only the flex a's (and then some of the higher end stuff) so they are effectively the same as the street advances but with a replaceable damper and stiffer spring rate.

Edfc may well be a good shout for what you want to achieve. My hesitation would be in spending that much in comparison to the cost of the suspension it'll be fitted to.

You're welcome to come out in mine at the next meet to see what the arb's are like (although mines on non teins now).

[S18 RSG 429]

6 minutes ago, Deacon said:

Ah ok - it was the spring rate that confused me. The street advances are 5kg front and rear - were yours a revalved special order?

The flex z's don't have the hbs only the flex a's (and then some of the higher end stuff) so they are effectively the same as the street advances but with a replaceable damper and stiffer spring rate.

Edfc may well be a good shout for what you want to achieve. My hesitation would be in spending that much in comparison to the cost of the suspension it'll be fitted to.

You're welcome to come out in mine at the next meet to see what the arb's are like (although mines on non teins now).

I have no doubt you're right actually. I knew the SA's were 1kg different to the Flex's, for some reason I thought I had seen 7kg somewhere, and that note on the Flex Z's explains why I didn't find them much better. Although strangely they felt slightly more suited to the road, even with stiffer springs. Perhaps it was just a placebo effect of assuming more expensive meant better.

EDFC always sounded like a good idea, but you're absolutely right, fitting a £700 set of electronics to a <£500 set of coilovers does seem a little OTT, and part of the reason I never really considered it. Also because of the fact that I've never experienced a car with it fitted, although I've experienced plenty of cars with stiffened chassis' etc. so I know what to expect.

Yeah I would appreciate popping out in yours when I get chance. From memory of looking through your list of mods, you've quite extensively upgraded various suspension bits, so I'd be very interested to see the results of all that.

[Church 209]

Fitting "£700 set of electronics to a <£500 set of coilovers" may seem not that bad idea, if result performs like £1500 set of coilovers. Usually one can get both comfort & track capability only on very high end costing £5k and up, with having to choose his poison in way of comfort OR track capability in low end. Hence dynamic real time adjustment by EDFC seems very interesting at least on paper, but IIRC those that fitted also said mostly good words about it.

[Tareim 343]

5 hours ago, S18 RSG said:

I have no doubt you're right actually. I knew the SA's were 1kg different to the Flex's, for some reason I thought I had seen 7kg somewhere, and that note on the Flex Z's explains why I didn't find them much better. Although strangely they felt slightly more suited to the road, even with stiffer springs. Perhaps it was just a placebo effect of assuming more expensive meant better.

EDFC always sounded like a good idea, but you're absolutely right, fitting a £700 set of electronics to a <£500 set of coilovers does seem a little OTT, and part of the reason I never really considered it. Also because of the fact that I've never experienced a car with it fitted, although I've experienced plenty of cars with stiffened chassis' etc. so I know what to expect.

Yeah I would appreciate popping out in yours when I get chance. From memory of looking through your list of mods, you've quite extensively upgraded various suspension bits, so I'd be very interested to see the results of all that.

you can go for EDFC 2 which is only around £250 for the hardware + fitting if you don't do it yourself this skips the GPS functions so just gives you the ability to change the dampening without getting out of the car

[Church 209]

But just manual adjustability from within car won't bring what wished imho - no dynamic readjusting on the fly for comfort in normal driving or stiffening what's needed on cornering/acceleration/braking/speeding to lessen that roll and so on .. just easier way to adjust vs turning knobs yourself. Hence imho not worth to spend anything on 'lesser set'.

[Tareim 343]

1 hour ago, Church said:

But just manual adjustability from within car won't bring what wished imho - no dynamic readjusting on the fly for comfort in normal driving or stiffening what's needed on cornering/acceleration/braking/speeding to lessen that roll and so on .. just easier way to adjust vs turning knobs yourself. Hence imho not worth to spend anything on 'lesser set'.

can't adjust the dampening on the move without it though, with it you can have a nice soft setup for daily driving/commuting, and then if you have the chance for a blast you can quickly stiffen it up without stopping and popping the bonnet to change it

[MikeB 79]

I have Street Advance with EDFC Active with GPS module and spent a lot of time looking and discussing options with Tein, plus going out in Lauren's car made my mind up the right way to go. I looked into Ohlins as they have there version of EDFC coming out but would be £4K plus and KW, BC's etc.

Street Advance come with 5kg springs front and rear as standard as I needed a smother ride and the option of revalving if necessary plus adjustability of going on the track. I have camber bolts on the front and RRG managed to get 2 degrees of camber and fitted whole system. No pillow ball mounts with St Advance but not really necessary if you are not into changing set ups. 

I also went back to standard anti roll bars and the cars handles great and EDFC is well worth it once you get your head around how it works and how you want it to work.

My wife is not petrol head but could tell the difference to previous set up and also when I change settings. Standard rebound compression is 16 clicks with EDFC you can change it to 32 or 64. 

So I have bit of halfway house and would recommend it as the roads round the Cotswolds are not the best and having had it all fitted for couple months now very pleased.

[Tareim 343]

how does edfc change the 16 clicks to 32/64?