Bilstein B8 -> Koni/GC

Currently selecting a new suspension setup, which consists of Bilstein B8 + (X) springs. I am quite keen on the Bilstein B8 unless anything else within a similar price range and quality can be recommended. I understand Koni Yellows can be had for similar pricing, but Bilstein seems to get most votes across the board.

The car is 95% daily driven and I've been quite used to a cheap height and damper adjustable coilover unit which probably required more damping for the spring it came with. The car now sits with stock EG suspension + front and rear strut tower bars. The front end sits lower due to the added mass of B18C, no air con. I would assume it still weighs more than the D15B.

What I'd like to know is what springs would be suitable to run with the B8 shocks. It would be good if somebody could clarify that these shocks can run up to 500lb/in (8.93kgf/mm) without sacrificing the longevity of the damper?

Only one set of springs will be used for street and track, so they need to be stiff enough to stay flat around the track but not too harsh for the streets; once again I've been riding around in entry level coilovers, so they probably came with 500lb/in springs front and rear anyway lol. I would like a more compliant ride but I'm able to tolerate a bit of bump.

Would
FRONT 460lb/in(8.21kgf/mm)
REAR 360lb/in(6.25kgf/mm)
be a good place to start?

According to an article on clubcivic.com, the H&R Race Spring runs the above rates for the DC2. Having looked at the amount of lowering the Race spring provides, I wonder if this will be too much? "Approx" 2.0" front and 1.75" rear.

On the stock EG suspension, the front sits lower than the rear with the added mass of the engine. I need the car to sit in between 1 and 2 "finger gaps" between the tyre and fender. Any lower and it will cause me issues. I will calculate how much lowering is needed from the current height to achieve that and maybe one of you suspension guru's out there may be able to help me out with an answer to spring rate and length.

I have been explained this concept once, yet still need some more clarification:

If two springs are different in height, the shorter spring has a thicker wire diameter and a higher spring rate. However both springs will give a similar ride height when placed on the same shock absorber. I have been told that even though the shorter spring of higher rate will make the car sit the same, it has a greater tendency to come loose when the car is jacked up or lifted off the ground. True?

So if I wanted to maintain the same spring rate with a properly seated spring, a longer spring is required? Also, I'm taking a guess that it would make the car sit higher?

Kindest regards
Michael

Also, I was considering the Mugen 5 way adjustables once upon a time, which I have found some spring rates for:

381F/252R

According to some, these are rather soft for track use. Which is why a combo like B8s and 460F/360R would probably be firmer all around?

After some research, some have also claimed that dampers such as Koni Yellows matched with 229F/156R springs are too stiff. Really? Apparently, it's due to the spring being too soft for the damper?

just a word of warning about spring heights
i have the h&r cup kit(look it up on the h&r site)
their figure of 2" lowering is very conservative to say the least, when i have them in at the highest perch on the shock i still tuck the front tyre about 10mm

I see. Thanks for the reply.

I have since been convinced that Koni Yellow+GC+custom rates+top hats is the way I wanna go. Anybody have much experience with the use of this combo? 430lb/in seems to be the most that Ground Control offers for EG. However, If the application is for Integra, 545lb/in is available.

Similar to the B8, Koni Yellow will only take around 550lb/in springs anyway, unless re-valved. I was considering 430F/350R. I suppose ride height is less of an issue with this combination.

Btw, do you mean that a 2" drop is actually more after the spring has settled in?

I think the Koni+GC just makes things alot easier. I don't have to choose spring height diameter etc. My decision is simply based on the spring rates.

the h&r site states about a 2" drop, straight away it was lower than that, then settled a further 5mm or so

i ran the gc sleeves before, they were pretty harsh on my koni yellows and i was only running 400/300lbs front and rear
then again i do have to drive on terrible sydney roads

they were much less comfortable than my cusco zero2's

Wow, I didn't expect that.

What stiffness was your Koni's set at? I thought the Zero2s had stiffer rates off the shelf compared to what you were running with the GCs. I would've thought that the Koni Yellow dampers would be more comfortable compared to an adjustable coilover damper.

koni's were set pretty firm, probably somewhere around the 3/4 stiffness region(whatever that means on the adjustable knob), any less and it would just bounce more from the linear spring rates

Michael, the B6 arent adjustable are they? Looked at Bilstein catalog and integra isnt listed in the B8.
Does that mean if you were to get the B8 shocks, the rear shocks will be fork type? not eyelet anymore?

Nope B8 and B6 are not adjustable from what I understand. However B8 might have a couple of machined grooves like Koni Yellows to allow circlip height adjustment.
That's right DC2/R is not listed in B8, however the B12 kit is available, which consists of B8 + Bilstein springs to match.
http://www1.carparts-cat.com/webkat....9018004&ROOT=1
find your way through honda, integra type r, suspension kit.
although it may not be locally available, i'm sure you'll find a way to get that if you were keen.
in this case, the shocks would be the eyelet type because they are designed for DC2R, however if you're getting off the shelf B8 by themselves, then only the fork type rear shock lower mount is available.

That's 713 euro per shock eh? approx $4.3kaud for a set without shipping? damn.

Koni + GC is a perfectly matched combo, it looks nice aswell, lol. It's pretty much a coilover setup. I wouldn't say they're less comfy that Zero 2's. I'm running Zero 2's and they're firmer than Koni. But i'm running 18kg 16kg springs. lol

MRK20CRX:
shit...18/16, surely not for road use right? The Koni Yellow SP3 seems to be another solution for extra travel on lowered cars. It's valved the same as OTS koni yellow, but the piston rod is 20mm shorter. Have you had much experience with the KY+GC on track? What spring rates were you using?

mocchi:
that i'm not sure, as i remember reading somewhere that the B12 is called B12 because it consists of B8 + 4 Bilstein springs or something like that, hence the name.
i think 713,000EUR sounds quite reasonable for a whole kit, before VAT and delivery and australian import tax. However i could be wrong...

Quote:

---

Originally Posted by MM89

MRK20CRX:
shit...18/16, surely not for road use right? The Koni Yellow SP3 seems to be another solution for extra travel on lowered cars. It's valved the same as OTS koni yellow, but the piston rod is 20mm shorter. Have you had much experience with the KY+GC on track? What spring rates were you using?

mocchi:
that i'm not sure, as i remember reading somewhere that the B12 is called B12 because it consists of B8 + 4 Bilstein springs or something like that, hence the name.
i think 713 EUR sounds quite reasonable for a whole kit, before VAT and delivery and australian import tax. However i could be wrong...

---

fixed :D haha. no way it costs 713,000 euro.
cusco zero 2 (dc2 8/6kg) is good for me. bit bumpy on steep speed humps but overall very nice.

what are you running now michael? koni+gc?

mocchi,
sorry, i misread the site haha 713,000 is a bit steep for suspension isn't it

i am yet to purchase the KY+GC. still considering what spring rates i should be using. guys in the states love going stiffer rear, softer front.
would love some opinions on running same rates front and rear and since i dont have a RSB yet, i wouldn't want to be running stiffer rates in the rear AND a big RSB upgrade.
but at this stage, KY+GC is my locked in decision.

currently back to stock suspension which i find to be a good thing after being in coilovers for two years.

considering they're only around the 1100-1200 USD range, i should be able to get them in for 1500 or so and that includes the KY, gc and
gc extended top hats.

Quote:

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Originally Posted by MM89

i wouldn't want to be running stiffer rates in the rear AND a big RSB upgrade.

---

Why not?

Don't bother getting the top-hats for the rear - the front is where travel is a problem.

There is no intrinsic benefit in a car remaining "flat" around a corner. If all your roll resistance happens at the front you're not going to be praising the flat cornering with the frustratingly overpowering understeer. Ground-Control offer any rates you like, you're not stuck with off-the-shelf items. I'm not convinced that it's possible to have a reasonable street setup which still performs on the track. I use 400/500 and it's quite OK on the road, but I'd like a little bit more for the times when the road is 10m wide, not 2m.

hi string,

the main reasons why i would want top hats for the rear is:

1) to me they are aesthetically pleasing

2) they contain urethane stem bushings. it may have been yourself or johnL or even someone else who mentioned that it's a good idea to swap the almost 20year old stock top hats for new top hats/upper mounts


the first part of your response seems to make sense, it will probably sink in a little bit more after a couple more reads.

im not as fussed about the performance on the street. so long as i'm not thrown out of my seat over a bigger bump, then i'm happy.
if i remember correctly, you drive an accord with koni yellows. how does 400/500 on an accord compare to 400/500 on a civic hatch?
from my understanding, with a lighter car, the rebound effect of the same spring rate as that to a heavier vehicle will be more pronounced?

can you provide some input regarding the koni SP3 shocks? are they worth the extra money?

kindest regards
michael

pretty sure johnl's the accord man while string's the ls man

*: I'm positive this forum hates me on a personal level. I was excited to write this post a second time but a third time; my heart isn't in it.

**: DA9, not Accord. The Integra is much closer to the mass/dimensions of the EG. I use DC2 Yellows with a 22mm rear ARB. Same sized tyres all round with a marginal track increase over factory both F&R.

Comfort is subjective. I drove for 100s of Km with a B20 in the boot 1cm from the glass - never moved. I don't know what bouncy means because perhaps, I haven't felt it. You certainly feel the bumps though, especially with spherical bearings disallowing longitudinal wheel movement. I think the term "crash" is appropriate. Even with 500lb/in in the rear, I feel harder hits riding my bicycle.

Lesser rant on handling: There is no value in remaining "flat" whilst cornering - weld your front shocks solid for a disastrous display of understeer. With body roll comes inevitable tyre unhappiness. If lessening body roll means happier contact patches then great - you've just optimised how your tyres behave when presented with their dynamic vertical loads. A 12f/8r set of springs gives the same* vertical loads for a given lateral force as compared to a stock setup - just with less roll and faster "response" time. You've optimised an element of a sub-optimal system. Honda decided to change the dynamic tyre loads by fitting the Integra Type-R with a huge anti-roll-bar at the rear. What spring rates will result in optimal load distribution for you? Don't know? Buy 3 sets (400, 450, 500) and try all the permutations.

My springs are 7f/9r and I certainly wouldn't want any more understeer - I find it difficult to enjoy front-stiff (which includes stock) FWD vehicles now since I feel they under-utilise the front end. If it wasn't so much damn fun (and the "rear stiff" setup really does kick-arse under power) I'd have moved on to a platform with the centre of mass at the other end.

* close enough for the argument's sake.

hi string,

i think you're wrong for once, i love reading your replies all the time. the terms used sounds all too similar to what is taught in static and dynamic motion.
please do not follow your heart's content for the sake of those who enjoy reading your feedback.

but i think i get what you mean by not to focus on remaining flat through cornering.
to be continued...

*: What I left out of my first comment was that I had written up two lengthy replies prior to the one above - lost the first one when the forum went down; "database error" and the second when I pressed some key combination which changed page and the back button didn't bring my text back... Frustrating.

The Australian dollar is quite good at the moment. If only I had spare cash I'd import a set of 700lb springs and some higher end Koni shocks.

haha i thought you were referring to some new members on the forum who despise you because you contest everything they say and
prove them wrong.

when you're saying that there is no value in remaining completely flat whilst cornering, is that because the increase (too much?) in roll resistance
will potentially decrease the available grip?
e.g. Using very stiff spring setup may cause the car to lift off the ground going over a bump at speed.

If you're ordering just the one pair of 700lbf/in springs, I'm sure spare cash is more than adequate.

Quote:

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Originally Posted by string

A 12f/8r set of springs gives the same* vertical loads for a given lateral force as compared to a stock setup - just with less roll and faster "response" time.

---

Could you please elaborate a little bit on this point? Mainly regarding the same vertical loads for a given lateral force.

From what I read and understood, the vertical load is applied to the spring from above and is mainly from the mass of the car. Would the 12/8 springs not require more force to compress 1mm compared to a 4/2 set of springs?


Kindest regards
Michael

I'm not sure where to begin without simply reciting chapter 5 of Race Car Vehicle Dynamics. How much do you know about the basics, like tyre load sensitivity and lateral load transfer?

In summary: Increasing all the spring rates by a constant factor (such as 3f/2r -> 12f/8r), ignoring nasty non-linear effects, results in the same distribution of vertical load (sum of vehicle weight and down-force) over the 4 tyres for a given lateral vehicle acceleration. A front heavy car with front stiff springs will still wipe out the front tyres when the rear tyres were only half way to their peak. Since it takes 4 times as much force to compress the springs the same amount, body roll will be greatly reduced, possibly enhancing (contact patch optimisation) how each tyre deals with the vertical force it is provided with. No matter what you do though, the front track still needs to provide 2/3 of the lateral force (the burden of having 2/3 of the mass at the front). In an ideal world, should the front and rear tyres give up the ghost simultaneously?

damn did the same thing string -- lost my post about 4 times tho!

Bottom line -- Search rr98itr user on Honda-tech.com for some GREAT posts on FWD suspension theory. His post started my quest for knowledge lol which ended with Milligans Race Car Vehicle Dynamics... Which is well explained, hardcore and you need to have your htinking cap on to apply the knowledge to a FWD perspective.

Also -- Spring Rates can be calculated but as rr98itr (scott) told me. The fastest theoretical setup may not be driveable at 100% whereas a slight compromise would result in perhaps a 96% top speed potential but 99% consistant application ie more attention can be paid to the race line rather than keeping the car on the road!!

Ewen who sometimes wonders why he tries to make a FWD go fast.

There's a reason that Milliken is littered with calculus; it is a hardcore topic. If you can understand the first 5 chapters you'll have a deeper understanding than any Honda-Tech thread I've ever come across.

well yeah, but it is focussed on RWD setups .. It doesnt go into the theory behind FWD setup in detail. I guess the honda-tech.com threads were great as a detailed introductory. Treat millikens as a degree of sorts --- it is a reference book! My mate actually got their new workbook, interesting!!

Still -- No one has been able to describe why the japs do it different to the americans -- Both have fast cars, wildly differrent setups!

Quote:

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Originally Posted by ewendc2r

well yeah, but it is focussed on RWD setups .. It doesnt go into the theory behind FWD setup in detail.

---

The examples "focus" on RWD setups for the same reason that the aerodynamics chapter is so early - it is a reference for full blown custom race cars. It doesn't need to present specific case studies for every configuration because the exact same mathematics applies. As I said above, understand the first 5 chapters and you're ahead of 99% of the game - 5 chapters which neglect to mention anything about which wheels are being driven.

Quote:

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Originally Posted by ewendc2r

Still -- No one has been able to describe why the japs do it different to the americans -- Both have fast cars, wildly differrent setups!

---

I think you're sensationalising the issue. You're comparing solutions to two different problems. Different tracks and competitions with different rules, different climate, different budgets, different available consumables.

Most high ranking H1 Honda Challenge race cars have spring rates less rear biased than Autocross guys racing around cones - much closer to those "wildy different" Japanese setups :)

Well -- it seems the japs stick to the 2-4hz ride frequency and setup the spring rate based on maths calc i.e. actual sprung weights and motion ratios .. I guess i need to clarify here. The purpose of the discussions i was involved in were how to make a fwd car turn (not necessarily consistently and easily repeatable -- ie may have the greatest potential to rotate and effect traction to front wheels however difficult to maintain consistently due to the inherent instability which enables the higher rotation rate...

I've seen some of the H1 racers with solid 30mm rear bars and small front bar with a factor of nearly 2x spring rate from front to rear (not wheel rate... but it'd be close). Compare that to some of the jap guys running near equal front / rear sway bar setups and softer rear springs relative to the front ... The actual physics behind it makes the US setup make more sense for fwd cars in terms of effective distribution of load transfer...

I know what you mean -- but there is still a significant difference... Even in the Phase DC2R, Spoon DC2R etc they all have similar setups to that above.

Interested in your thoughts / response --- Always learning and understanding the WHY between two different setups for similar purpose is critical..

Rules may form part of it -- unlikely.. Climate, no. Budgets? well, sure, but unlikely. Still need the part, just diff spec. And assuming all have same access to parts etc ..

I've heard and felt first hand the effect of removing the front sway bar to increase the rear stiffness ratio -- i don't understnad why you would want to increae front stiffness ratio.. Its taking away load transfer onto the driving wheels effectively when cornering!

Ewen who neeeeeeds to open up vehicle dynamics again.

I've found a place online to purchase "Race Car Dynamics"
It's only $97, with free shipping from the UK, much cheaper than anywhere I've seen in Australia.

www.bookdepository.com

Anyway, back to the topic,

Recently I have been leaning towards the SPSS3 valved Koni's. Reason being they will handle the higher rates in the future if necessary.
I won't be needing any GC top hats with this setup and bottoming is apparently unheard of (or close to) on these shocks. Once again,
heard nothing but good feedback on this setup.

Considering the car will not be seeing much of Melbourne roads in the near future, SPSS3 + 550f/r might be a good move? Please
suggest some rates otherwise.

With the SPSS3 + GC, I'm unsure of a reliable place to purchase from. I've found weaksauce to be around the $1600USD mark not shipped
and another place by the name of Redshift Motorsports to be cheaper at $1359USD not shipped.
http://www.redshiftmotorsports.com/R...ne%20Store.htm
Would LOVE some input regarding this Redshift place due to the pricing.

Thanks in advance guys

worth the purchase, to save on shipping get their workbook as well, and latest publication!

yeah man, i'm onto it. but it's free shipping i believe :)

I am VERY open to alternatives for places to purchase this suspension kit.

Ha ha, I just paid for a set of SPSS3's a couple of days ago - second hand though. For only 550lb/in springs they're a bit of overkill but if you're looking to upgrade in the future...

thats good to hear string. i'm assuming you'll be running something upwards of 550lbf/in on the spss3?

to be honest, i'm not quite sure what would be necessary for a track like winton, which is the track that i go to.
i know the tight hairpins may benefit from some extra spring, especially in the rear. 550lb/in may be a good place to start with?

redshift motorsports seems good, their price is definitely pulling me towards that direction; and for that same reason i'm
a little uncertain. and plus a thread like this http://redshift.informe.com/koni-gc-...ions-dt80.html
isn't the biggest confidence booster..however i have also heard other good things on HT: http://www.honda-tech.com/showthread...ift+Motorsport

now this tells me that they were all good and well in 2005 and something went wrong during 2007 according to the dates on the posts.

shoot these guys a pm or email to see what price they can do for you
got my old gc sleeves from them last time, pretty sure they do the tophat's you're after too

oh no limit, yeah have heard of them as well.

with the spss3 i'll be giving the top hats a miss. won't need the extra travel as the shock is already a fair bit shorter.

what was the shipping costs if you don't mind me asking?

was about the 100us range back when i got only the sleeves and springs in

mind you, i brought in a h&r sport cup kit from tirerack earlier in the year for about 180us via fedex

Quote:

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Originally Posted by MM89

thats good to hear string. i'm assuming you'll be running something upwards of 550lbf/in on the spss3?

---

The 400lb/in I have in the front at the moment are a bit 'slow' and are stopping me from going as low as I would like to. I've acquired 12km/mm (670lb/in) and 14km/mm (780lb/in) springs so the regular yellows have to go!

Definitely won't need top-hats with a 25mm shorter shock.

ordered a set of koni spss3's yesterday from top performance in vermont.
they are the koni distributors in melbourne and i highly recommend them.

very willing to discuss and teach their customers.

now just need to wait for the american exchange rate to jump up a little bit...

good luck with the new sussy :)
hope you have no regrets about it all

i've settled on a h&r cup kit for my ek street only car and don't see myself changing anytime soon :)

only regret is that i didn't purchase the ground control kit any earlier to avoid the dip in the exchange rate. oh well.
i think NLM has the cheapest price around at the moment for the GC kit. $322USD + $100ish USD shipping.

when ordering the kit, spring rate, spring length and I.D is also required, correct?

for the GC kit, is only 2.5" ID avaialble? or 2.25" as well?

is there a fairly common spring length that most people use?

Spring length is up to you and will determine if and how much the spring is preloaded at full droop for a given height setting. With a shortened shock with a droop limiter (i.e. spss3), you won't want to go for a stiff 8" spring or you won't be able to get the top-hat on unless you're slammed to the ground. Standard off the shelf GC rates run 8" front and 7" rear springs. 6" springs don't seem to be common until you get to the more serious rates (800+). When I had 400/500 8"/7" on the DA, the highest I could go without a spring compressor (i.e. slight preload by hand) was about 2" lower than stock.

You need to tell them which shock you are using - there are different GC kits to accomodate for different OD shocks. Go for 2.5" diameter springs - there's millions of them around second hand.

I would offer to sell you my spare GC kit but you want your own spring rates. The exchange rate sure is a shame.

i would prefer that all the springs are slightly preloaded at full droop. let's hope that 550(8")/550(7") - 2.5" ID will do so at approx 2" lowering.

don't the spss3 and the koni yellows share the same ground control kit?
i thought both shock bodies share the same outer diameter?

http://sphotos.ak.fbcdn.net/hphotos-..._4039187_n.jpg

Picked these up at Vermont today. Now I know what everyone means when they say Koni provides really basic instructions. Ground Control in another 2 weeks (hopefully).

nice one mm89

so you settled on 550lbs front and rear?

i've called up ground control and they've given me a ball park around 450 front and 550 rear. so the car rotates a bit more.
i was thinking more along the lines of 500, 550 rear + 23mm type R sway bar/24mm asr sway bar + asr brace.

by the way, ground control is willing to ship it off to me for 65 bucks at the moment because he was mentioning something about
bulk shipping...originally they quoted 140 through email. so i'm gonna seal the deal tonight at like 2am lol
mega win!

500/550 7" all around!

http://sphotos.ak.fbcdn.net/hphotos-..._3158610_n.jpg

So i received the ground control kit today!
Just removed all the stock coilover units and shall be taking out the top hats tomorrow and installing these babies!
i never realised how short 7" really was until i saw these!

very interested to see these fitted, can you please do before and after. I skipped a few pages, can you tell me if these are height adjustable?

what are you referring to when you say before and after?
these are height adjustable through circlip grooves on the shock body, where the circlip sits and the ground control snaps on.

the ground control kit allows you to adjust the height by adjusting the preload of the spring, however i don't think the adjustment of the preload is designed for aesthetic purposes.
however, setting more preload will raise the car and less preload will lower the car.

just wondering..

on the stock shocks, the dust boot fits between the thick washer and the thin washer.

on the koni's, no dustboots have been provided and i have heard of people's steering rack boots or modified stock dust boots rub against the spring.
to my understanding, there is no issue in not using a dust boot as many have done so in the past without any dramas.

since i won't be using a dustboot either, that means there won't be anything in between the thick and thin washers.
is it imperative for something to be in between or may i go without one, without having any side effects.

this is something that people haven't mentioned when they don't use dustboots, whether or not something (such as a rubber washer) should go in between the two washers.

cheers

^nope no need

problem with finding dust boots is finding ones that are no bigger than 2.5" OD to fit under there
i gave up looking after buying a set and not using it

SWEET!! thanks vinnY, i knew it would be either you or string to my rescue! haha

shall be on by tomorrow!

just a word of advice incase you don't already know

the front shocks, remember to tap off the stock bottom mounts(ring bit that helps position the bottom forks on the shock)
i ran without it for ages without a problem but i still wouldn't recommend it :p

thanks vinny, yeah i did that so i didn't need to cable tie the brake hose bracket.

i just finished installing these after i came home from work..haven't had a drive yet.
I've set the spring preload to the minimum, so that the spring sits down without moving around. not much lower than stock.
Will have to see how much difference there is after a quick drive though.

Quote:

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Originally Posted by MM89

thanks vinny, yeah i did that so i didn't need to cable tie the brake hose bracket.

i just finished installing these after i came home from work..haven't had a drive yet.
I've set the spring preload to the minimum, so that the spring sits down without moving around. not much lower than stock.
Will have to see how much difference there is after a quick drive though.

---

so how did you go?
how do you set preload on springs anyway?

Quote:

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Originally Posted by MM89

I see. Thanks for the reply.

I have since been convinced that Koni Yellow+GC+custom rates+top hats is the way I wanna go. Anybody have much experience with the use of this combo? 430lb/in seems to be the most that Ground Control offers for EG. However, If the application is for Integra, 545lb/in is available.

Similar to the B8, Koni Yellow will only take around 550lb/in springs anyway, unless re-valved. I was considering 430F/350R. I suppose ride height is less of an issue with this combination.

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what would happen if the konis were installed with say.. 850lb/in springs?
or say.. 50lb/in springs?

i've set the preload of the spring according to the height that i would like it to be...from a performance point of view, probably not the best way to go about it - should be corner balanced

on an 850lb/in spring...it'd be bumpy on the roads, i haven't tried it, so i can't comment too much..but that's approx to 15kgf/mm...i'm on 500/550 and it's still bearable driving around..wouldn't wanna go more..

as for a 50lb/in spring, you would probably bottom out regardless of the ride height..

Quote:

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Originally Posted by MM89

on an 850lb/in spring...it'd be bumpy on the roads, i haven't tried it, so i can't comment too much..but that's approx to 15kgf/mm...i'm on 500/550 and it's still bearable driving around..wouldn't wanna go more..

as for a 50lb/in spring, you would probably bottom out regardless of the ride height..

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i should've explain myself more clearly sorry, i meant in regards to shocks life not ride comfort.
for example, would the shock strut be overheated on a particular area because of suspension travels on same area all the time, instead of over whole strut, spreading heat over whole strut if that makes sense?

that means you chose your springs based on weight of car or approximation of how stiff you want your ride to be?
not based on the shocks or shock travel?

damn im confusing.

reason that im so curious about your setup and your spring choice is because i've got some shocks that needs some springs.
and wondering if stock itr springs is too soft for the shocks.

the shocks have 13cm of full shock travel, bump stop is 7cm give or take a mm.
so thats about 6mm of play. hmmm.. im worried that itr springs will be too soft and hits bump stops all the time
over potholes or speed humps.

maybe i should measure stock itr shock travel and the bump stop.. hmm mind leap isnt happening.

help! lol

I think stock itr front rate is 250lb/in linear and same for the rear but it is progressive which I'm sure you would know
I remember someone saying on HT that running stock itr springs on the spss3 shocks were fine, no bottoming or hitting bump stops.
What shocks are they?

Quote:

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Originally Posted by MM89

I think stock itr front rate is 250lb/in linear and same for the rear but it is progressive which I'm sure you would know
I remember someone saying on HT that running stock itr springs on the spss3 shocks were fine, no bottoming or hitting bump stops.
What shocks are they?

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older style ohlins, clip type perches. part number is ct7-s0200-50
ct7 ones, been trying to get some more info but there is so less on the internet.
saw someone asked for more info on these ct7 types on HT but no reply. :(
made in japan not sweden.

oh, and the perch takes oem style springs, not like your eibach springs.
gc uses eibach yea?

thanks for help btw mike, appreciate it.

The amount of travel after a bump stop has been included sounds quite similar to the spss3's at around 60ish mm.
Would you consider using any coilover sleeves and springs? Running any swaybars?
I would probably run slightly higher rates than stock itr. Just to be on the safe side.

sway bar is stock eg4 gli front sway bar, rear is 25mm.
when you say just to be on safe side, you mean in case there is a massive pot hole
i ran through it and it destroyed the bump stop and blow the shocks?

if i can get my hands on a spring compressor asap... damn!

but. found this and this calculator, so i might not need to actually jack up the wheels to see
how far it can travel before hitting bump stop.

.... i think i should do both.

So you can remove the perch and retain the circlip on the shock?
If so, then that's pretty easy because the ground control or perhaps most sleeve simply sit on the circlip with a machined lip that covers the circlip. In effect, circlip failure is almost eliminated.

Yeah ground control uses eibach universal 2.5" inner diameter coilover springs.

I'm glad that there is some discussion going on, what has helped me could help others too

Quote:

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Originally Posted by MM89

So you can remove the perch and retain the circlip on the shock?
If so, then that's pretty easy because the ground control or perhaps most sleeve simply sit on the circlip with a machined lip that covers the circlip. In effect, circlip failure is almost eliminated.

Yeah ground control uses eibach universal 2.5" inner diameter coilover springs.

I'm glad that there is some discussion going on, what has helped me could help others too

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i think i will email the gc guys because they dont have the ohlins options. how did you go with the konis btw.
liking it?

Yeah exactly that. Running up to approximately 8kg/mm all around should still be quite street friendly. I can't see the calculator now as I'm on my phone, but an 8k spring will decrease your chances of bottoming on unexpected potholes. 8k was simply an estimate and also everyone's classification of street friendly will differ.

When you get a spring compressor, try and use the hook type. I used a flat angled surface spring compressor and it would slip alot. It was my first time using one, so perhaps this contributed.

I'm unsure if my assumption is correct, but a bigger swaybar will add roll stiffness/resistance, similar to using a stiffer spring. I would imagine this to be providing extra prevention to bottoming. However with your situation, that would apply to the rear end.

You're right, they don't. Someone may have inquired for ohlins as well in the past, if not they'd be able to fab it up. This would be quite costly though..

The setup is quite good. Won't really find out how good it really is until I hit up winton again.
Would have thought 9k/10k would be quite stiff. But it's on the limit

Quote:

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Originally Posted by MM89

Yeah exactly that. Running up to approximately 8kg/mm all around should still be quite street friendly. I can't see the calculator now as I'm on my phone, but an 8k spring will decrease your chances of bottoming on unexpected potholes. 8k was simply an estimate and also everyone's classification of street friendly will differ.

When you get a spring compressor, try and use the hook type. I used a flat angled surface spring compressor and it would slip alot. It was my first time using one, so perhaps this contributed.

I'm unsure if my assumption is correct, but a bigger swaybar will add roll stiffness/resistance, similar to using a stiffer spring. I would imagine this to be providing extra prevention to bottoming. However with your situation, that would apply to the rear end.

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yeah swaybars will add spring rate. im thinking of getting 8kg front and 6kg rear.
reason being, the cuscos that m currently using is 8/6kg and i find it good.

would love to feel the difference.

ok so a friend of mine was so nice to dropped off a spring compressor for me. so..
disassembled the itr shocks.

found out that the stock shocks has 7cm bump stop, 14.9cm shock travel
so it has 7.9cm shock travel before hitting bump stop.

one thing i noticed was the stock itr shocks are softer by about maybe 1/3rd of the ohlins. 1/2 of the ohlins at least.
i need 2-3 times as much force to compress the ohlins. does that makes sense?

maybe the ohlins will be good for track. damn i wanna try it.

what are the effects of having soft springs with stiff dampers?
ans: Overdamping is the opposite, the damping rate is too high in comparison to the spring rate. This is bad because it puts a lot more strain on the suspension mounting hardware, as the bumps are barely absorbed by the suspension and is translated into chassis movement instead. This means that a moderate bump can cause your tires to be airborne for a moment. Obviously not good unless you’re racing on a really really smooth surface. source

or stiff springs with soft dampers?
ans: underdamping, extreme example is blown shocks. bounce up and down until the springs settles itself.

edit: fail. strut hole in itr top hat is too small for the ohlins strut. FAIL.

http://i516.photobucket.com/albums/u...e/P1010461.jpg

update: im stupid. the bushes can be popped out. (-_-)
swapped the top hat bushes and in it goes. now just need to order some lowered and harder springs.
hmm.. H&R or Eibach hmm..

vinny give me some advice! is it hard to get internet in japan? bring me some souvenirs hehe.

could you reuse the stock itr metal cylinder that goes between the two top bushes?
i would've thought that the ohlins use a bigger diameter shaft.

just a word of advice when you're looking around for springs.
if you're gonna be using coilover springs on sleeves, i would suggest going for a spring slightly longer than you think you may need.

for example, i went for a 7" long spring, front and rear. in the front, it's fine, i am able to lower it a fair amount.
however, in the rear, it's not quite long enough to lower the car anymore. there is a bit of difference between front and rear ride heights.

with a longer spring like 8" you will have more flexibility of setting ride height.

Quote:

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Originally Posted by MM89

could you reuse the stock itr metal cylinder that goes between the two top bushes?
i would've thought that the ohlins use a bigger diameter shaft.

just a word of advice when you're looking around for springs.
if you're gonna be using coilover springs on sleeves, i would suggest going for a spring slightly longer than you think you may need.

for example, i went for a 7" long spring, front and rear. in the front, it's fine, i am able to lower it a fair amount.
however, in the rear, it's not quite long enough to lower the car anymore. there is a bit of difference between front and rear ride heights.

with a longer spring like 8" you will have more flexibility of setting ride height.

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your hunch is spot on. i had to swap the top hat bush because ohlins strut shaft is 12mm, oem is 10mm.
the metal hollow cylinder is also the same, oem has 10mm ID.

me always being unlucky, the metal cylinder on the ohlins bushes are missing, there is only 1 cylinder among all bushes.
as if it's telling me to go on a quest for metal cylinders!! how annoying.

i was thinking of using oem metal cylinders and drill out the ID.

8" is 20.3cm? that is pretty short lol!

i will definitely get at least 8"

will there be enough metal to drill it out to 12mm??


8" is short, but the design of the ground control sleeve will work well with this length. perhaps what i need for the rear.

you don't want to be using too long a spring because of the extra mass and also less flexibility in adjusting ride height.


the issue with the ground control sleeve for the koni shock body (not sure if this would apply to other brand of shocks using GC sleeves)
is that the sleeve will turn when you are trying to adjust the spring preload. usually using some wd-40 will help and a good strong hand to grip onto the sleeve while you're trying to adjust the perch.
some people claimed to have used ONE layer of electrical tape to make the shock body just thick enough to prevent the sleeve from spinning, this did not work for me because even the one layer of
electrical tape was too thick.

also, mine did not come with an adjustment spanner, so i filed down a piece of flat metal to fit in the grooves on the adjustment perch with some assistance from an adjustable spanner LOL

Quote:

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Originally Posted by MM89

will there be enough metal to drill it out to 12mm??


8" is short, but the design of the ground control sleeve will work well with this length. perhaps what i need for the rear.

you don't want to be using too long a spring because of the extra mass and also less flexibility in adjusting ride height.


the issue with the ground control sleeve for the koni shock body (not sure if this would apply to other brand of shocks using GC sleeves)
is that the sleeve will turn when you are trying to adjust the spring preload. usually using some wd-40 will help and a good strong hand to grip onto the sleeve while you're trying to adjust the perch.
some people claimed to have used ONE layer of electrical tape to make the shock body just thick enough to prevent the sleeve from spinning, this did not work for me because even the one layer of
electrical tape was too thick.

also, mine did not come with an adjustment spanner, so i filed down a piece of flat metal to fit in the grooves on the adjustment perch with some assistance from an adjustable spanner LOL

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hehe pretty creative. but i will be getting oem style springs where the bottom/top isnt flat.
im thinking either H&R or Eibach, any other springs that offers oem style? no dont want kings lol.

the cylinder thickness is 2mm for oem,
ohlins is 1.5mm.

other than drilling them out, what other options you reckon? i don't even know where / how to drill the cylinder haha. arrrrr!!

well if cylinder thickness is 2mm for oem and you plan to drill the inner diameter out from 10mm to 12mm, you'll be left with 1mm wall thickness.
strength would be weaker regardless. i'm guessing it'll probably deform if you squeeze the cylinder back into the bush. not sure if that's gonna be a big issue, but i personally don't like any part failing on my car, especially if its caused by my error.

what you need in the correct dimensions should be available at a bolt and nut store or hardware shop.

Spoon has springs that fit to oem style shocks. Koni also makes springs to fit. JIC does. There are many out there. The question is, can they hold their actual spring rate over time and what is the variance in claimed and measured spring rate. Eibach and H&R are very well known. I'm happy with the eibach springs, but who's to say there isn't better something out there. I simply paid the price the I wanted to pay and got the product that I expected to get.Hypercoil is apparently as good as it gets. But pricing will follow suite.

Quote:

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Originally Posted by MM89

well if cylinder thickness is 2mm for oem and you plan to drill the inner diameter out from 10mm to 12mm, you'll be left with 1mm wall thickness.
strength would be weaker regardless. i'm guessing it'll probably deform if you squeeze the cylinder back into the bush. not sure if that's gonna be a big issue, but i personally don't like any part failing on my car, especially if its caused by my error.

what you need in the correct dimensions should be available at a bolt and nut store or hardware shop.

Spoon has springs that fit to oem style shocks. Koni also makes springs to fit. JIC does. There are many out there. The question is, can they hold their actual spring rate over time and what is the variance in claimed and measured spring rate. Eibach and H&R are very well known. I'm happy with the eibach springs, but who's to say there isn't better something out there. I simply paid the price the I wanted to pay and got the product that I expected to get.Hypercoil is apparently as good as it gets. But pricing will follow suite.

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i think i will get h&r. will check for metal cylinder sleeve at my local nuts n bolts shop.

thanks bud

Found good shock settings yet? You surely must be impressed by the fast yaw response time coming from soft and understeery progressive springs.

Quote:

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Originally Posted by string

Found good shock settings yet? You surely must be impressed by the fast yaw response time coming from soft and understeery progressive springs.

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are you asking me? i didnt try the stock springs, too long and i already know its gonna be too soft so didnt bother trying them on.

Nah asking the guy with a real man's suspension setup :)

haha they're quite good..it feels like it's never gonna understeer though...kinda hard to adapt to coming from the typical high front, low rear rates.

it's good that you asked about shocks settings, cos i've kept them at the softest. what brilliant advice do you have on offer today string??