Sorri for the OT but how do stock rexxys go at Wakefield?
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Sorri for the OT but how do stock rexxys go at Wakefield?
not dat fast
Best time: 1:14.8950 (official transponder)
N15 Pulsar SSS 2.0L SR20DE
Genie Extractors, stock cat back! (mmm quiet...)
Nismo 1.5way Mechanical LSD
Tein HA
Ferodo DS2500 pads, EBC Turbo slotted rotors
Silverstone 'Type RR' DOT Semi-slicks w/Sprint hart 15x7" +37
Cusco 3point rear strut brace
Cusco 4 point front underbody brace
Whiteline rear 20mm bar
All whiteline bushes + camber kit.
Hoping to dip into the mid-low 14's next time now with full 2" exhaust increasing peak power and able to rev though 7.5K without struggling, also will be using different tyres for next time too.
Oran Park this weekend, can't wait...
Thats a nice time CoZZm0!
Cheers mate. Lots of work gone into the car to bring it to that level, and i'm sure there's some car improvment, and certinaly some driver improvment to be found yet..Quote:
Originally Posted by wynode
Just finished a great day at Oran Park south circuit, posted a 0:53.2540, so i was pretty happy with that time.
:)
Intersting to see the times of different makes of cars, I'd love to get my mx5 out there to see what it can do ( I'm from Melb)..... maybe a 1.10:D
If your MX5 is race preppred with slicks, certinly possible.Quote:
Originally Posted by mossy
are stock suspension realli limiting on track?
ive been to wakefield 3 times now
and while my best lap of the day is improving
it is getting faster only by tenths of a second
im realli frustrated becasue i know my car is faster than this
after re-reading alot of people's posts on b16a cars with suspension mods
they are getting like 1:17's
i feel so slow!
do suspension realli shave off a few seconds when used to full potential
my fastest is 1'20.8 now
full stock EK4 with 195/55r15 GIII's
yes gelo...
G'day everyone,
For what it's worth, Wakefield is our local test track and we're generally there once a month or so doing testing.
We had an EK Civic Vtir Coupe project vehicle on the fleet that we used to develop the Civic product. The best time we got in the dry was 1:15.9 but could circulate comfortably in high 16's.
Driver - Wojtek R. Whiteline R & D manager
Engine - Standard
Brakes - Hawk pads
Tyres - Yokohama ES100 205/50/15
Suspension:
Whiteline "Group 4" coil-over kit. (Spring rates 6kg/4kg mm fr/rr)
Whiteline "Handling Pack" including front and rear adjustable swaybars, front caster and camber kit, rear camber kit.
Whiteline Chassis Bracing package including front and rear strut braces, B pillar brace, rear lower arm/swaybar mount brace.
We generally keep engine and other components standard as we're out to test chassis mods only doing lots of comparison work with data logging. Brake pads are often upgraded simply to give us more capacity for laps on the day.
Our R & D guys, who are not race drivers but enthusiasts still maintain that it was one of the sweetest cars they ever drove on test. From a chassis side it felt wonderfull inspiring a lot of confidence.
If nothing else, this time should give you some sort of benchmark of the potential of "chassis-only" mods for a street car.
Hope that helps
Cheers
Jim
Whiteline
from what ive gotten out of Wojtek - the EK4 he drove previous , was totally stock engine wise - as he puts it " JUST chassis mods".
Very interesting :)
Jim, just to add to the benchmark:
my DC2 VTiR managed a 1:14.9 (transponder timed) with 'just chassis mods' and a set of 4-1 headers on R tyres... did some 1:15's and several 1:16's quite comfortably
well - the mods were Cusco coilovers (12k/8k), whiteline 24mm rear swaybar, ITR brakes, no strutbraces, no alignment mods, no chassis braces, no air intake mods (stock filter), 2.5 year old Proxis RA1 tyres...
your EK would be quicker with harder springs i reckon ;)
Hi everyone,
Spring rates of 6kg/4kg used were as per "Circuit/Road" spec Group 4's to suit road tyres. If we were running R spec tyres we would reccomend and fit "Race" spec spring valve combination at around 7.5kg/5.5kg. High performance road and or R spec semi-slicks can not generate enough grip to warrant spring rates in excess of 8kg, particular when used on a relatively poor surface track like Wakefield.
For what it's worth, most cars we test and develop with at Wakefield will see a 1.5 to 2 second per lap improvement when using R spec tyres vs performance street tyres and another 2 seconds for slicks. For example, our P-Rex XRD (Tarmac rally setup '97 STi with pro driver) holds the club record on slicks at 1:05.80 using Michelins, our P-Rex I (99 WRX with gifted amateur) had a class win at 1:08.27 using Dunlop D-01's. Best case for similar car with performance street tyres using a good setup is late 1:09's or low 10's.
As a rule of thumb, expect a 2 second reduction per tyre class change. So I would suggest a DC2 VtiR on R spec with a good driver should be able to get into high 13's to low 14's if properley setup, particularly with some extra power and better brakes.
Apart from all the above, we did not post lap times as an absolute or as a challenge to others. We do not use race drivers for testing road setups and nor do we compare results from different days when weather and track conditions can dramatically vary the results. Our testing is about acheiving predictable handling with consistency while logging maximum sustainable G's and handling bias. Its also done primarily for road/weekend race hybrid product which is our main market. We can and do prepare some tarmac rally cars but these are not driven on the road and can be designed more toward a race biased compromise.
Best
Jim
Whiteline
whoah, for sure Jim, no challenge or absolute perceived!!!
we're just setting some benchmarks...
do you think my VTiR would benefit from fr/rr strut braces and increased camber?
my tyre wear was very even http://forums.clubrsx.com/attachment...hmentid=154709
(this was my best tyre)
my current alignment settings are 0,0 toe allround with factory camber of about 1.8 degress
Tinkerbell,
You'll certainly benefit from more chassis bracing, you can read why in general here. http://www.whiteline.com.au/faqelse01.htm#Chassis and strut bracing . The heavier the spring and swaybar rates the more benefit to be found in a stiffer chassis.
However, and with all jokes aside, I would bet you a set of springs that you will go faster at with much softer springs than you have now. Camber settings are probably OK as you can generate enough grip with those springs to compress the wheel adequately need more more neg camber. Also, try some toe out on the rear, say up to 1.5mm total toe out.
Cheers
Jim
Whiteline
i would love for you to explain how 12k fr and 8k rr springs might be affecting my (and anyone else on the traditional japanese coilover route) lap times negatively...
i was running 400lb (7.1k) fr and 300lbs (5.3k) rr springs on koni yellows in my old LS Integra and found these too soft on most circuits (particularly EC)
that was with a custom 23mm Whiteline rear bar.
by 'too soft' i mean that i thought body roll was excessive...
(thanks for your comments Jim, i know lots of other guys will be reading them with interest, that is the good thing about such a specific Honda forum, comments in relation to one persons car will generally be translatable to many others.
it is wonderfull to have such an experienced suspension expert join Ozhonda.com)
I would also really like to hear about this too, as I am currently searching for a good set of coilovers for my track only ED civic, and I was looking at getting some spring rates similar to what tinkerbell has 12/8.Quote:
Originally Posted by tinkerbell
I always thought that without going too extreme, stiffer is better on track. I would of defiently thought that 7.5/5.5 would be too soft. As on track it is usually much smoother than street, so you dont need to take as many bumps.
G'day everyone,
Thanks for the kind words.
I'll take some time to answer this properly so we can use it on the suspension tech forum, give me a few days. It's a very popular question and points to one of the most popular retail misconceptions in suspension tuning. We have a lot of material used in training to explain why but need to format into one of our tech discussion papers.
In the meantime, please consider following;
- HRT's V8 Supercars use front rates of around 12 kg on a car that weighs considerably more, runs on slicks and would lap Wakefield in under a minute.
- Our P-Rex XRD (97 Sti) used 8.5 kg to do the 1:05's.
- The fastest road based car we run at the moment is Project EVO VIII which is primarily setup for tarmac rally but was configured for slicks for an endurane race at Wakefield last December. It qualified 2nd on the grid at 1:04's and used 9 kg.
- There is a direct relationship between tyre grip potential and spring rate. The more grip you can generate the more spring rate you need. Conversely, the lower the grip potential the less spring rate you CAN USE.
- There is a direct relationship between road surface and optimum spring rate. The better the road surface the less suspension travel you can get away with and consequently the higher the spring rate you can GET AWAY with (though not neccessarily need).
Be back soon
Cheers
Jim
Whiteline
Sounds very interesting there Jim.....welcome to Ozhonda and we look forward to your reply.
Excellent information you are sharing with us. Thank you.
Are these spring rates that you are mentioning just in relation to Wakefield. I think I saw somewhere that you said that its surface was not too smooth. What about on a smoother surface? Would it be wise to increase the sping rate a bit? Have you had any experience with Phillip Island?
Hi Jim, names Alfy.. Are you an actual representative for Whiteline?? If so, I am really interested in getting a front Strut Brace for my EK civic.. How much would I roughly be looking at spending??
Alfy:
http://www.whiteline.com.au/
part number KSB570 = $239
[QUOTE=_CiVIC_]Hi Jim, names Alfy.. Are you an actual representative for Whiteline??QUOTE]
Signing his posts as "Jim" might indicate that he is Jim Gurieff.
btw - i always throught comparing spring rates between different cars was pointless due to different motion ratios as defined by the type of suspension system?Quote:
Originally Posted by Whiteline
G'day everyone.
I started putting together an elaborate answer over the weekend and realised that it all sounded rather familiar. A quick check of the www.suspensionparts.info forum showed that I'd already covered around 90% of the issues in one of our Tech Talk series. Here's a link to the specific thread;
http://www.suspensionparts.info/show...=&threadid=272
Would be happy to continue with further questions or discussion after that.
Alfy, we try not to talk about sales or pricing on forums etc, would rather keep it technical. Would you mind contact one of our distributors or our sales area on sales@whiteline.com.au.
tinkerbell, you raised a very good point re comparisons of spring rates, I guess I took this issue for granted and as a given when commenting before as it works toward our argument in a way.
All common suspension systems have a motion ratio, by this we mean that the wheel and spring do not move at the same rate for a given amount of travel. Its a standard part of our design process and we measured, the EJ-EK to have a spring to wheel motion ratio of 0.67:1 at the front and 0.81:1 at rear.
That means that for every millimetre of wheel travel at the front there will only be 0.67 mm at the spring. The rear is a little closer at 0.81 mm at the spring for every 1 mm at the wheel. To put into context, most conventional strut based cars like Commodore and WRX will have a ratio of around 0.95:1. Needless to say this will have a bearing on the actual spring rate at the wheel which is significantly more important than the rate at the spring and what we actually calculate when we design our suspension products.
As for the affect this has on the numbers specific to the Civic, I'll let the above settle a little bit before we go further. ;)
Cheers
Jim
Whiteline
thanks for the link Jim, nice forum there :)
Quote:
Heave and Pitch modes need sufficient rate to stop the car bottoming out over uniform bumps or the front or rear axles running out of travel as this would have the same effects as excessive resistance on a loaded wheel as detailed above. Specifically, we run the risk of a tyre(s) momentarily losing contact with the road leading to loss of grip. In simple terms, this loss of grip is part of what you feel when the car understeers or oversteers. Understeer being a relative loss of grip on the front while oversteer is the relative loss of grip in the rear.
but, i see no 'reasons' there Jim, could you eludicate?Quote:
Whiteline believes in using as little spring rate as absolutely possible for these reasons. We start from a small amount and increase, as we need it, not the other way round. As a full range suspension manufacturer, we believe in using the right component designed for each job to deal with its chief responsibility. That’s why we use swaybars and not springs to control body roll. We would no more design a swaybar to hold a car up in pitch or heave than we would try to get the spring to hold the body up in roll.
i understand that stiffer springs may bounce & lose contact with the road - but this is dependent on the quality of the damper is it not?
if springs push tyres onto the road, would not stiffer springs help this?
what is the disadvantage of using stiffer springs on the track? and on the road?
from my thoughts and things ive learnt
harder spring rates actually push the car further from the wheels...
harder spring rates = less weight (when moving and tranfering of weights through cornering, braking and forward acceleration) on the wheels
IN TERMS OF PITCHING
so a harder FRONT spring/damping rate would mean MORE WEIGHT pushed towards the rear (or less weight pushing to the front) wheels leading to more UNDERSTEER
and a harder REAR spring and damping rate would mean MORE WEIGHT PUSHED TO THE FRONT meaning less weight on the rear and more OVERSTEER... so a front 8kgf rear:12kgf MIGHT actually make the car OVERSTEER HEAPS MORE IMO
but i do believe there is more to that
IMO i think that spring rates have to be relative to the suspension's CAMBER CHANGE during the travel?
i think thats why they have relatively HARDER spring rates (and less travel) on race cars
cos if the travel movements move too much, the CAMBER will be changed too much, which makes setting an OPTIMUM CAMBER (keeping a good tyre contact) very hard
thats why the DOUBLE WISH-BONE suspension system is preffered??
cos the camber does not CHANGE as much during the TRAVEL since it has 2 pivot points or something...?? making it possible to have better handle even on softer spring and damping rates?
G'day everyone,
tinkerbell, apologies if it was not entirely clear for you.
The optimum spring rate for a car is that which is enough to hold it up in place and to deal with the anticipated suspension travel (pitch, heave) and loading resulting from cornering (some portion of roll). No more, no less.
As the post discussed, warp modes arguably dictate "0" spring rate as an ideal to ensure the tyre to road contact patch is maximised. All suspension and chassis design is about maintaining articulation of the wheels over the road surface. We compromise warp functionality because we need spring rate for pitch and heave but excessive spring rate here will compromise warp even more.
And why is that such an issue? The simplest example is to imagine a car fully loaded into a corner, the outside front wheel suspension is compressed 50 mm or with a load of 500kg assuming a 10kg spring rate. That same wheel then hits a surface change like undulations or tarmac edge, the loaded wheel can no longer soak up or absorb the surface change hence passes this change directly to the chassis of the car. The chassis pulls away from the road and takes the wheel with it momentarily and, for a short but none the less significant time the tyre losses contact (or quality contact) with the road reducing available grip to that wheel which reduces available grip to that wheel pair etc etc.
This is where the tyres grip capacity come into the equation. The more grip the more cornering G's you can generate hence the need for more spring/roll rate to compensate and maintain suspension travel. Hence why a dedicated race car using slicks needs say 9kg and -4.0 camber to pre-empt the load but what would happen if you used these settings for a road car with road tyres on a track? The tyres would not generate sufficient grip to need the spring rate so the negative camber becomes a major liability when accelerating and braking and is not used when cornering. The excessive spring rate then leads to skidding under lateral load as the transferred weight can not be used by the tyre because it won't roll. And, the wheel wont compress to bring the camber back into neutral to maximise the contact patch.
I hope that makes it clearer.
DOHCVTEC, believe or not, weight or load transfer is to be avoided in setup as it constantly changes each tyres grip potential and it is affected by heavier springs. Swaybars don't actually affect weight transfer. Its a sometimes contradictory dance that is always a compromise unless you can use 3rd and 4th springs as in Formula 1. A lot of the oversteer and understeer you refer to is actually as a result of weight exceeding the capacity of the tyres grip potential, not loss of weight.
Its important to remember that any camber is a pre-emptive setting used to provide a relatively flat surface and optimised contact patch when cornering. Its a liability in almost every other occasion. Modern strut based cars also have problems with migrating roll centres which exacerbates roll during cornering where as double wishbones do not.
Cheers
Jim
Whiteline
oh, so it is 'warp' you are worried about?
it is still not clear, but i think it seems that that is what you are trying to say, i think you need to dumb your language down to explain such simple concepts (no offence) just so it is accessabile to everyone...
does the DC2 integra have double wishbone front suspension?
I was under the impression that the DC2 and EG civics run a double wishbone setup.......Quote:
Originally Posted by tinkerbell
what is spring rates of the whiteline EK performance (lowered 1.5") springs.??
is this about 300f and 250r? jsut want to make a comparision to how stiff the springs u guys are talking about? This conversation is getting quiet interesting..
yeah, about that.
DC2R springs are that too...
Hi Everyone,
Honda Integra DC2 has a double wishbone front and rear suspension configuration.
The spring rates for Whiteline lowering springs for Honda Civic EK are 245lbs/in front and 100>185lbs/in rear.
Hope this helps.
Regards,
Wojtek.
Whiteline Automotive
from my conversion 245 pounds / inch is equal to roughly 4.34kg/mm.
Would it be true to say, that there are a number of solutions that can achieve the same goal and that each solution has it's advantages and disadvantages?
I personally have been on different spring/shock rates and right now, I have a preference for the heavy rates :D
Currently I am running 14kF/12kR (around 780lbs - F and 670lbs - R) - with close to -3 degrees camber on my DC2R - and normally run a DZ02 on the track.
Yes, correect. That is why we choose the softest spring rates with big sway bars.Quote:
Originally Posted by euGeR
Result = more compliance (increased grip) + adequate roll control + reduced chassis and component stress + improved tyre wear + easier to drive (less fatigue on driver) + etc...
Can I ask what spring/shock combinations you have tried? What are your results and comments on each?
Can I ask for your tyre temperatures for all variations?
Naturally, we would also need to know your total suspension set-up and tune, including wheel alignment settings, tyre brand/size/model, tyre pressures, ride heights, sway bar sizes, spring rates, shock valving (graphs).
Looking forward to your reply.
Regards,
Wojtek.
Whiteline Automotive.
so if i get bigger front swaybar, i could reduce my front spring rate from 12k to say 8k?
it is already 24mm stock, should i get a JDM Type R 25mm one...?
i have the WL 20-22mm rear sway bar already, can i drop down to 6k rear springs?
what size springs will i need? 61mm or 64mm - anyone know what ID (internal diameter) and length Cusco coilover springs are?
also - what about the Whiteline castor kit - does it really increase castor by upto 6 degrees?
Woaa 6 degrees!!
I didn't get anywhere near that NOR anywhere near what the article on the whiteline site (the red EG si) says. With 16" rims the most I got was around 2.5 degrees.
Quote:
Control arm shim-caster adj
1 / 2 / Shim adjust +1 to +6 deg range / Honda Caster Kit / HONDA CASTER KIT
Code: #KCA301
Price: AU$43.91 (Australian Dollars)
NOTE: Australian deliveries must add 10% GST
seems to me that the Whiteline webstore it is representing that it is upto +6 degrees castor...
i would like to know, as it seems quite an adventurous claim for only few washers and a new set of bolts to achieve...
factory stock for DC2 = 1'10" +/- 1'
I'm thinking we should make a new thread tinks......but when I read this it said:
However after getting my kit fitted......I didn't have even 3 degrees of positive caster.........so I was a bit shocked.Quote:
The red car has a massive 5 degrees of positive caster.........
Hi Everyone,
tinkerbell,
Yes, Bigger sway bars allow to use softer springs, relatively. What are the ideal spring rates for your car??? Don't know. Don't know enough about your car. But, you can use our Civic EK Group'4 spring rates of 6kg/mm front and 4kg/mm rear with 27mm front and 22mm adjustable rear sway bars... etc... as a base line.
KCA301 - caster kit, adds up to +2.5 degrees of extra caster.
(description in our webstore is being changed)
Regards,
Wojtek.
Whiteline Automotive.
If you use soft springs u have a greater reliability on the sway bar?Quote:
Originally Posted by Whiteline
Then you will get subframe tear outs..
I've been running stock shocks/springs with upgraded front and rear swaybars for around 2-3 years now and have tracked the car. No problems yet (touch wood).Quote:
Originally Posted by BlitZ
oh hey... it looks like we have a whiteline rep. in here....
have you got it on the hardest setting?Quote:
Originally Posted by wynode
what is your laptime around wakie?.......I think issues arise when you start pushing hard.
Quote:
Originally Posted by MKI4EVA
Yeah hardest setting. I've been on stock springs uptill a month or so ago when I swapped to DC2R springs (slightly stiffer than stock). Apart from that everything else is stock, sussy wise. First time on wakefield was 1:21.6x on street tyres.
Someone trying to say I don't push it hard enough?Quote:
Originally Posted by MKI4EVA
Hey Wojtek,Quote:
Originally Posted by Whiteline
I've been on:
+++++++++++++++++
Eibach - 9kg/6kg progressive + Bilstein (they say groupA) - valving unknown. It was a 41mm piston from memory
Nice weight transfer, bit to much roll but was quite uncomfortable on the road.
- Not sure on tyre Temp, but found about a 6psi difference after a couple of laps. Street tyres - mainly RE71's
Ride heights were about a 15mm drop F and 20mm R
I must say braking felt good with this set up, felt like I was getting the right amount of "dip". Sometimes some rear wheel lift in cornering as well.
Zeal S6 - 12kg/8kg Aluminium coil over - valving unknown but adjustable.
I think this rate is just about perfect on a DC2 road/track - quite comfortable still (I think my kidneys can handle more than most) and good feel on street tyres.
Found it soft when I moved from a Street tyre to a Dunlop DJ01 - psi difference of 4-5, but biased as sometimes i didn't push that hard due to tyre scrub against the guards
Setting was 610mm F to wheel arch 610mm F
Current - Showa steel bodied coil over - straight spring - adjustable bump
14kg/12kg
Valving
0.01m/sec F 15.3／-17.6kgf R 10.8-11.7kgf
0.02 36.5-32.0 21.4-17.4
0.03 62.3-46.1 36.9-21.7
OEM sway's
I have found these feeling more comfortable than the bilsteins on the street. On the track they feel extremely sharp with - had a few comments that guys loved watching the car in the corner - just looked extremely balanced and flat (that made me happy :D )
The main difference is, I feel that I'd pay for it more if I made an error - more likely to break traction or get a "pushing" feel rather than turning.
I've since adjusted the rake to be more "level" between F & R and find this alot better.
F toe out about 4mm and R - 0 toe - keeps it straight under brakes and turn in is crisp! (have tried toe out R, toe in F and R - but prefer the current configuration)
Cornering feels extremely stable and controlled, with a better "drift" which can be adjusted with driving (turn in slightly earlier) - I'd almost say more predictable.
Cornerweight with me in the car (but apparently it made only a 3kg diff).
Tyre's fluctuate about 3-4psi. With the new feel, I hope I'll pick up an extra second or two!! :D - but I'm definately loving this set on Dunlop DZ02.
Heights:
605mmF 600mm R
Now
595mmF 590mmR
(free data!)
Rake = 10mm lower at the F (measured at to chassis)
Right now I'd say the natural camber from lowering a double wishbone is having good effects!!
(by the way, I'm no pro, I just like collecting and analysing my own data :D))
The next set - I would like to try a set of Koni 3811 and adjust the sussy through testing. Think that would be fun! haha
euGeR,
Thanks for your data so far. In order for me to make some sence, could you please provide shock valving graphs, tyre temperatures, ride heights (absolute ride height, measured from centre of wheel to guard), full wheel alignment settings at the very least.
Eitherway...
I understand that you have not fitted uprated sway bars with any of your suspension kits. Can I ask for your reasons for not using bigger sway bars?
We have tried to explain the benefits of using bigger sway bars here and in other threads and forums, but it seems the information is not being acknowledged.
Could you explain the reasons for not using bigger sway bars please?
Component failure is not a unique problem to a Honda. Other cars break mounts, brackets, links, etc... as well. We provide solutions where required.
Regards,
Wojtek.
Whiteline Automotive
sorry, but the information has been 'acknowledged', however, you really have failed to prove the benefits of your position.Quote:
Originally Posted by Whiteline
that said, i am getting a set of the 61180065 XRD springs to put on the rear of my car and move the 8k springs to the front.
plus getting 25mm front sway bar.
and moving the 22mm rear bar to full stiff position...
just so i have tried it out myself to compare pros/cons
No, I am sorry. I think you have failed to understand this issuue. Let me try again.Quote:
Originally Posted by tinkerbell
Hypothetically.....
If for a given standard tyre, we need a certain amount of roll resistance, let's give it a value of 10 units.
These 10 units of roll resistance can be acheived by using either a spring, a sway bar or a combination of both.
Let's assume that the factory suspension has 7 units of spring roll resistance and 3 units of sway bar roll resistance.
Now, the car is fitted with a semi-slick tyre (more grip), which requires a higher value of (total) roll resistance. Let's assume this to be 14 units.
This can be acheived by either;
Case #1;
spring roll resistance of 11 units + sway bar roll resistance of 3 units = 14 units of total roll resistance
Case #2;
spring roll resistance of 9 units + sway bar roll resistance of 5 units = 14 units of total roll resistance
I think it is very clear which is a better combination.
Let us know if it's still unclear or you do not agree.
Regards,
Wojtek.
Whiteline Automotive.
Hi Wojtek,Quote:
Originally Posted by Whiteline
Unfortunately I don't have the old shock dyno graphs (even though I would like to get one done to have some piece of mind that everything is in order), but the inconvenience of pulling the coil overs off and taking them for a dyno (not to mention the cost) is not viable
The best I could give you is the ride heights and wheel alignment's.
You are welcome to organise a test day for us to attend and test. I'll be happy to let anyone who can heel toe drove my car at wakefield! (my clutch doesn't like anyone who cannot heel toe - whiteline staff that is - no joy riders ;) ).
As for Sways, with the current setup, I don't feel a need for them, as I feel that I don't have all that much roll. I considered them prior, but opted for the higher rate springs and shocks.
I guess it came down to "understanding" the effects and feel, and how can it be tuned further.
As I understood it, to rectify roll when using a higher grip tyre, you could
a. upgrade sways - no sacrifice to ride comfort
b. go with stiffer shock/spring set up - sacrifice to ride comfort but improve weight transfer
My previous experience with moving up spring/shock rates was positive so I guess I just tried it again!
We hobbyists, don't have to much of a budget to try alot of things and sometimes opt for the safer route :D
your opinion that 'it is very clear which is better' is the issue.
ie it is NOT very clear WHY it is better.
why is sway bar roll control better than spring roll control?????
why is it 'clearly better'????
would there be a difference in the stroke of the shock?
example -
Case #1
have less stroke/ suspension travel?
Case #2
More stroke or suspension travel required?
nah, the premise is based on rates only.
and the premise, although glossed over, is that:
http://www.suspensionparts.info/show...=&threadid=272Quote:
In which case, we can ask the question what is the ideal spring rate needed for “warp” modes? Many, including Whiteline will argue that the theoretical ideal rate is effectively zero, none, zilch!
so on this basis, WL, amongst others, believe that lowest spring rates (ie close to zero) are best to overcome the issue of individual changes in road surface creating loss of traction at that wheel.
see:
what is not mentioned is that an anti-sway bar not only transfers individual changes in the road surface to both wheels attached to the anti-sway bar, but compounding this is that the movement across the chassis of the single irregularity might lead to a doubling up of the effect fo the irregualrity - on the opposite side of the chassis.Quote:
Roll is best controlled by swaybars. Why not springs, you ask? Consider what happens when the car is loaded into a corner in roll and one or both of the loaded wheels encounter a change in road surface through a warp mode? Remembering the law of equal and opposite reactions, a loaded outside front wheel encountering a bump will encounter a significant rate through the pre-compressed spring (car is loaded in corner) resulting in the spring passing on the load to the body that will move away from the road. Result? Lost contact, even if only for a moment but potentially disastrous from a handling point of view when you consider its doing a great deal of the cornering work at the time.
is this not as "potentially disastrous from a handling point of view"?
this is one often cited reason for 'balance' of anti-sway bars with spring rates.
quite the opposite of, as WL cites, a dominance of sway bar rate over spring rate.
still - the proof will be in the pudding...
i am getting a set of 6k springs for my car, to replace the 8k rears, and moving the 8k rears to the front, replacing the 12k fronts... adding a 25mm front anti-sway bar and moving the rear anti-sway bar to stiffest setting...
main reason - better street driving comfort ;)
...Quote:
Originally Posted by tinkerbell
Hi Everyone,
tinkerbell,
It seems that you are seeing this as black and white, i.e.; extremely high spring rates with standard sway bars, or zero spring rates with massive sway bars.
Some of our (WL) explanations were put forward to illustrate a point, that we choose to use springs only as stiff as they need to be, no more. That is not to say that we do not believe in stiffer spring rate, as that is not true. I think you will see that in case#2.
It is all a case of balance, balanced interplay of all suspension components, rather then grabbing for for biggest hammer (spring) that one can.
My previous reply #117 in this thread....
"Yes, correect. That is why we choose the softest spring rates with big sway bars.
Result = more compliance (increased grip) + adequate roll control + reduced chassis and component stress + improved tyre wear + easier to drive (less fatigue on driver) + etc"
A good case in point as to why excessive high springs rates with standars sway bars are not an ideal solution was shown on GTP cars recently (if that is what they are still known as...). I am not sure if anyone has seen this, but their last round at Eastern Creek, turn 1 (~200km/h), one of the cars, I think it was an EVO, started to repeatedly pitch uncontrollably in the rear, and subsequently lost control and spun out. I don't know the exact reason for this, but I am sure that had it been softer sprung with bigger sway bars, this would have been less likely to occur. BTW, GTP cars are free with shocks and springs, roll bars cannot be changed = compromise.
euGeR,
Understand about the difficulties with getting the extra data.
Do something for yourself, and consider getting a tyre pyrometer. It will give you invaluable information about your car. It's a must for suspension tunning.
The two cases were based on rates only.
Regards,
Wojtek
Whiteline Automotive.
thanks for persevereing Wedge, i see that you finally reveal that compromise is the key to balanced suspension,
so it is not really a case of, to use your turn of phrase, grabbing for the biggest crowbar (sway bar) one can?
i am glad you have acknowledged the 'middle way'... :thumbsup:
i'm still going to *try* the soft(er) spring bigg(er) bar approach, just so i can judge from empirical experience :)
but i might wait to feel the results before i employ the soft(est) spring bigg(est) bar approach WL seem to advocate...
as i understand it, bigger anti-sway bar will increase total spring rate...Quote:
Originally Posted by euGeR
can WL confirm?
very interesting discussion here.
Anyway, didn't get timed last time I went to wakefield. Had semi slicks on the front, and was running pretty well by the end of the day. Pretty sure I was faster than before.
Previous time, had street tyres, and best time was 1:19 (coilovers, front and rear strut bars) and exhaust.
A couple of things have changed on the car now, better brakes for one, so should do much better when I'm ready to go back.
This July 5th Q..........come along!
Sorry wyn. Got plans already. Going to be at the slopes skiing for the whole week.Quote:
Originally Posted by wynode
Maybe when spring hits and the snow has melted, I might go back to wakefield sometime lol. Thanks anyway. :)
I though it would be a good idea to write up a conclusion to what has been discussed in this thread, as there is a lot of information spread over a lot of pages here. As well as this I will also try to answer some of the outstanding questions and doubts.
I’ll just start by saying the most effective way to reduce lap times around a circuit is to increase the cornering speeds (or lateral accelerations). As probably all our cars have negligible aero packages, mechanical grip is the only way to achieve this. With all things being equal, the way this is achieved is by having the softest possible suspension setup that will not allow the roll and pitch of the car to effect the tyre contact patch excessively (by giving to much camber change etc). The soft setup allows the wheel/tyre to track any undulations and uneven road/track profile, staying in contact with the road, and hence being able to generate grip. If a tyre is not in contact with the road then it cannot generate grip, this can arise whilst running high rates. Also when running high rates, grip cannot be generated as efficiently when the tyre is still in contact, because the uneven track conditions setup uneven loading in the tyres. Rally cars are trying to reduce this very phenomenon with hydraulically linked front and rear anti-roll bars, effectively spreading any high single wheel loads (from uneven track) to the other wheels (effectively reducing the load variations).
As an example to show that softer ride rates are advantages, the Mclaren F1 of a little while ago, still probably one of the greatest high performance road car (supercar) ever made, runs a fairly soft suspension rate. As an equivalent ride rate, a civic EK4 would need to run on approx. 2.5 kg/mm springs to attain the same rate as the Mclaren F1.
Now what circumstances will warrant higher rate springs/anti-roll bars in an application? By increasing the friction coefficients at the road (for example switching to slick tyres) more lateral acceleration can be achieved, this will increase the roll rate during cornering, and possibly upset the tyre due to excessive roll camber. Here fitting of stiffer suspension will reduce the roll, and camber effects seen at the tyre back to the original values, hence reduce any undesirable grip effects associated with the roll camber and increase the possible grip further. Now the best option here would be to fit a stiffer anti-roll bar, and this will deal with the increased chassis roll, while leaving the ride rate unaffected for the mechanical grip.
One reason for running higher rate springs would be to control chassis movement very precisely due to very large aerodynamic down force (F1). This is where the chassis needs to stay within a few “mm” of its position with load changes in the order of 1500kg. Quite simply, aerodynamics in F1 is the driving force; you can get away with a bad suspension if the aero package works well. So racecars that run huge amounts of down-force (to develop they’re grip) require stiff springs. If there is no aero then there really is no need to use springs of such a high stiffness.
It is clear that there are some differing opinions in ways of achieving roll stiffness and its advantages or disadvantages. Let me start by saying that to be absolutely correct roll stiffness not only depends on anti-roll bars and springs, but also dampers and the roll inertia of the vehicle. However to keep it simple, we can neglect damping and inertia rates, effectively assuming steady state cornering.
As it was stated earlier, one can use any combination of spring and anti-roll bar to achieve the desired roll rate. However one needs to look at what the effect will be by using different combinations. One thing to consider in this argument is that springs affect the ride rate (aka heave), where as the anti-roll bar does not effect the ride rate (that is purely vertical motion – it should be noted that one wheel bump rate is affected, although its effect is small on comfort).
The big advantage to this is that the springs can be adjusted to give the required ride rate and then the anti-roll bars can be used to adjust the roll stiffness to the desired value. This way the springs can be tuned to provide optimum mechanical grip.
On the other hand if spring were primarily relied upon, the ride rate would be much higher and ultimate grip may diminish (and increase NVH).
Additionally another advantage of using anti-roll bars is the possibility of easier adjustment. One could swap the springs on the front end (if you had the time, and spare sets of springs) or by simply adjusting the hole position on the anti-roll bar arm. Anti-roll bars are still used on the highest forms of motorsport to adjust the handling characteristics quickly (from formula ford to F1).
As stated before, I neglected the dampers for the explanation, although it should be noted some of the differing opinions about comfort said here about different types of suspension brands (even when using the same spring rate) is almost certainly due to damping coefficients. This is because for the best comfort a damping of around the 15% critical is used, and for best grip around 45% (values as a general example), and the difference between comfort and grip can really be felt. Racecars can use values approaching critical damping (100%).
I should also say that no matter what your suspension setup, weight transfer (or load transfer) during cornering is only a function of the CG height, track of the car, and cornering acceleration. It may be affected by excessive roll angle, which moves the CG sideways, although it really needs to be excessive roll to see this. Roll angle is dependant on the roll rate (spring and ARB) and suspension geometry (roll centres) as well.
Regards,
Jakub
B.E. (Mech.)
Whiteline Automotive
i think u guys should post in another thread coz it's getin very difficult to read the times that ppl have posted.
i mean this is a thread bout wakefield times after all
sorry jer, seems the thread morphed into something it wasnt.
Holy thread revival!!!!! this is a great thread...
tink... was wondering if you could outline a comparison of your previous setup to the below change.
Quote:
Originally Posted by tinkerbell
ha ha!
yeah, the 8kfr 6krr wasnt good for track events,
especially at eastern creek, so i went back to the 12k fr 8krr for the whole 2007 year of supersprints.
here are my times from 2007, i am car 62:
http://home.exetel.com.au/tinkerbell...c2007times.jpg
Dave = gangsta streetz racer hahaha :D
Mad times mate!!
Have never been there but hoping for 1:07s this week :)
Times are based on the Newmann GTR which runs low 1:04s and we are 2 secs slower than them at QR and Wakefield should suit our crx much better as QR is HP track. Be interesting~
Good luck this thursday :thumbsup:Quote:
Originally Posted by ONE600
just heard they did 1:07
HIPOWERRACING CRX 1:07 excellent for first time... see new thread from hipower
Car: 99' DC2R
Mods: Coilovers,zorst,cat,extractors,CAI,oil cooler.
Track: Wakefield
Time: 1:13.5
Condition: Slightly Damp (was after a night of heavy rain)
clutch was screwing up - wasnt selecting and grinding sometimes :( (time for a aftermarket HD clutch...)
and track was slightly damp when this time was set....
might just be your clutch fluid needing a bleed...
most likely.. but it still the stock clutch... prob could do with a HD one.... maybe a light flywheel but i dont wona loose torque :p
yeah, you might want drain the torque valve too, it gets worn out... it is just near the flux capacitor...