Ride hight 2

[Petrus]

Thanks Dev.
In my experience in 23 years of roád racing is that the softest settings you can get away with stability wise, gives the most grip.
It is more unsettling than a harder stable car, but the tyres need to be able to follow the road to have traction. Hence negative wheel travelis só important for grip on real world roads.

p.s. concerning the Tein spring values, it must be taken into account that they assume standard shocks.

[Nvy]

Some more concrete data:

The Cusco 18 mm arb has 180% of OEM stiffness at the soft (outer) hole, 260% in the hard (inside) hole. This is the bar Orido uses in the Spirit MR-S. Front standard.

The Whiteline 18 mm has foúr position; from soft to hard (out to in), quite surprising; 65%, 100%, 130% and 160%.

Now, assuming the TRD one being in the same position as the standard one, than it would be 113% stiffer.

If this shows anything first and foremostly, then it must be that one must try FIND THE SPECIFICATIONS! of any mod.

The lowering springs too are surprising in the very same way.

TRD
Front Coil Spring K=15.6N/mm (Ride height approx. 20mm lowering)
Rear Coil Spring K=33.6N/mm

Tein
Front 1.9Kgf/mm (30 mm. lowering)
Rear 2.9Kgf/mm

Notice the surprising element? It is not the stiffness but the fron/rear difference; 100% in the TRD kit, 50% in the Tein springs.
Oh, the second surprise is that TRD goes stiffer at the rear than Tein while lowering less!

I do not know what the standard springs are.

Mr.Orido suggests wayWAY harder spring setiings; road: 5, 6, 7 kg. front, 10 rear.

I want to add Orido´s summary of the front/rear setting; ´front soft ok; standard stabeliser ok; rear hard rate, hard stabeliser; easier to control.´
In numbers:
5 kilo front, standard arb
10 kilo rear, Cusco stabeliser
Basically... we are sissies 

p.s. a stiffer arb will also have a stiffening side effect on the springing.

I have Meister coils with 5kg front and i find it too soft as the car bounces all the time no matter what damping settings i have. Rear seems ok but front is a nightmare. I think ill get stiffer springs 7 front and 10 rear. Atm i have the OEM sway bars.

Also the spring types behave differently that should be taken into account.

[Petrus]

Thus: 
MeisterR Front 5 kg/mm.
Ofcourse with non standard (variable) damping.

It agaín illustrates the different specifications of aftermarket goodies.

[Petrus]

As a matter of interest, with the TRD Sportivo kit came the advice to run  front 205/45R16, rear 215/45R16 high grip tyres on 7J ET45 rims.

[Gaz mr-s]

[quote author=Nvy

I have Meister coils with 5kg front and i find it too soft as the car bounces all the time no matter what damping settings i have. Rear seems ok but front is a nightmare. I think ill get stiffer springs 7 front and 10 rear. Atm i have the OEM sway bars.

Also the spring types behave differently that should be taken into account.
[/quote]

Nvy.... I bought them too, but not yet fitted.  I know precious little about suspension, but I'd suggest if you cannot get the front end to stop bouncing you have a damper problem.  Maybe you should consider going to a suspension expert.  From what I've read from others who have had Meisters for some time, maximum damping is for track work.

[Petrus]

H&R supplies lowering springs for 20 or 30mm lowering.
I have , perhaps sofar, no others apart from TRD that ´only´ go 20mm lower. The rest is 30mm with some offering 40 to 45 mm. even.
Not found, again sofar, any spring válues.

H&R also offers specially tailored springs for the (adjustable) Koni Sport coil over set.
They state 30mm lower with standard weight car. No data on spring values.
Koni does provide info on the damping; soft 125% of standard to hard >200%.




I have a very high opinion of Koni (a Dutch firm ;-)  ) and thus assuming (I know; stupid) that the spring rate will be moderate too. Nevertheless have the question sent to both them and H&R.

[Petrus]

H&R have responded;
Front 20 N/mm. (approx 30 mm lowering)
Rear 30 N/mm.

TRD
Front Coil Spring K=15.6N/mm (Ride height approx. 20mm lowering)
Rear Coil Spring K=33.6N/mm

Tein
Front 18.63N/mm (30 mm. lowering)
Rear  28.44N/mm


Standard spring values anyone???

[Beachbum957]

We are running Tein springs and Koni inserts at 3/4 turn from full soft.  There is no float or bouncing or other odd behavior.  You can crank up the rebound adjuster beyond about 1 1/2 turns from soft and make the car handle worse as high rebound "packs" the suspension down over a series of bumps (the suspension doesn't extend quickly with high rebound damping). 

We removed the rear anti-roll and stayed with a stock front, as the rear bar tended to lift the inside wheel in tight turns and cause snap oversteer with the stiffer Tein springs.  With the current setup, the basic characteristic is light understeer even when pushed hard, which is a good plan for a street car.

[Dev]

Some more concrete data:

The Cusco 18 mm arb has 180% of OEM stiffness at the soft (outer) hole, 260% in the hard (inside) hole. This is the bar Orido uses in the Spirit MR-S. Front standard.

The Whiteline 18 mm has foúr position; from soft to hard (out to in), quite surprising; 65%, 100%, 130% and 160%.

Now, assuming the TRD one being in the same position as the standard one, than it would be 113% stiffer.

If this shows anything first and foremostly, then it must be that one must try FIND THE SPECIFICATIONS! of any mod.

The lowering springs too are surprising in the very same way.

TRD
Front Coil Spring K=15.6N/mm (Ride height approx. 20mm lowering)
Rear Coil Spring K=33.6N/mm

Tein
Front 1.9Kgf/mm (30 mm. lowering)
Rear 2.9Kgf/mm

Notice the surprising element? It is not the stiffness but the fron/rear difference; 100% in the TRD kit, 50% in the Tein springs.
Oh, the second surprise is that TRD goes stiffer at the rear than Tein while lowering less!

I do not know what the standard springs are.

Mr.Orido suggests wayWAY harder spring setiings; road: 5, 6, 7 kg. front, 10 rear.

I want to add Orido´s summary of the front/rear setting; ´front soft ok; standard stabeliser ok; rear hard rate, hard stabeliser; easier to control.´
In numbers:
5 kilo front, standard arb
10 kilo rear, Cusco stabeliser
Basically... we are sissies 

p.s. a stiffer arb will also have a stiffening side effect on the springing.

I have Meister coils with 5kg front and i find it too soft as the car bounces all the time no matter what damping settings i have. Rear seems ok but front is a nightmare. I think ill get stiffer springs 7 front and 10 rear. Atm i have the OEM sway bars.

Also the spring types behave differently that should be taken into account.

One of the problems with most monotube designed struts options for this car is being over dampened for a street application. This is a case where they assume you are going to track the car but for some unknown reason they suggest lower spring rates for comfort on the street  which  tend to be worse. That is why a struts damping and spring rate has to be matched. 

A few more points for food for thought.

A monotube struts spring rate cannot be compared to a twin tube design with similar spring rates but most of all the kind of damping the strut provides. 

Koni makes decent suspension but the option for our cars are inserts. Inserts use even less shock oil then the factory dampers.  It's still not comparable to a  good coilover system. 

There are only a few good options if you want to do it right.

[Petrus]

We are running Tein springs and Koni inserts at 3/4 turn from full soft.  There is no float or bouncing or other odd behavior.  You can crank up the rebound adjuster beyond about 1 1/2 turns from soft and make the car handle worse as high rebound "packs" the suspension down over a series of bumps (the suspension doesn't extend quickly with high rebound damping). 

Thanks for sharing the experience.
Totally logical.

We removed the rear anti-roll and stayed with a stock front, as the rear bar tended to lift the inside wheel in tight turns and cause snap oversteer with the stiffer Tein springs.  With the current setup, the basic characteristic is light understeer even when pushed hard, which is a good plan for a street car.

While I totally understand it; it is a fundamental property of the arb and the reason why they are a nono for a bit more serious offroading, it is diagonally opposed to what TRD does with a stíffer! rear spring.

@Dev; ofcourse quality/functionality of a ´proper´ coils over system is superior to a system costing a third/half.


p.s. a biggie here is the same as in Germany; I nééd homogation papers with whichever part I mount. I can easily swap out a pair of seats for periodic inspection nor ar they going to be any probelm with a copper, strikingly painted suspension bits are a different kettle of fish.

[thetyrant]

Some good reading and information on this thread , i am a big fan of the Koni sport dampers on the many different cars ive used them on including my 2, they offer a nice balance between improved handling and ride comfort due to the valving they use,  my current setup is Koni Sport Inserts, Tein Springs, trimmed bumpstops f&r with Camber bolts in the front and on the road with Konis set +90 to +180deg up from full soft it absorbs the bumps well (considering the travel available) and car body is well controlled,  on track turned to +180 or +270 handling is further improved for the smoother circuits and while springs work ok they are both a touch soft and low for what i would like, but for an off the shelf option is was the best one for me and i looked at them all.

In future i would like to convert the stock damper casing to take an adjustable spring platform to take a conventional coilover type spring (2.25 or 2.5") and this will allow me to play with the rates and heights etc, i know the Koni damper can easily handle double to stock spring rate so keen to explore this and see how firm we can go without spoiling the ride quality too much, its always a compromise somewhere but i think raising car a touch and going up on spring rate to a sensible level will still give a nice balance of ride and handling.

In the meantime as a stop gap more than anything im going to play with uprated ARB's and have some Whiteline adjustables due this week to start fiddling with!, this is mainly to help reduce the body roll in tighter corners on track and while im not one to try and get the car flat as possible with mega stiff suspension and believe some roll is good as it aids traction but im hoping the ARB's give a sensible reduction in roll without compromising traction and ride too much, until i get chance to play around with springs etc.

[Petrus]

have some Whiteline adjustables due this week to start fiddling with!, this is mainly to help reduce the body roll in tighter corners on track and while im not one to try and get the car flat as possible with mega stiff suspension and believe some roll is good as it aids traction but im hoping the ARB's give a sensible reduction in roll without compromising traction and ride too much, until i get chance to play around with springs etc.

Will be interesting to read your feedback.
The two opposed ´views´ are both based on the driving experience and largely (to not write exclusively) based on driving style.
Note to all; an lsd fitted should be separate subject as that changes the arb traction issue fully.

[Petrus]

Found a value for the stock spring rates on Spyderchat.
So, that makes:

Standard
Front  14.5 N/mm.
Rear   22 N/mm.

H&R (30 mm lowering)
Front  20 N/mm.
Rear   30 N/mm.

TRD  (20mm lowering)
Front  15.6N/mm
Rear   33.6N/mm

Tein (30 mm. lowering)
Front  18.63N/mm
Rear   28.44N/mm

[Petrus]

So....

Let me think out loud in print.

Taking the damping out of the equasion because asuming that is matching the spring rate, we are left with spring rate and anti roll bars bars.

It stand to reason as a lighthouse that the TRD set up leans towards mild understeer out of legal caution.
That explains the slightly beefed up front arb.
Since for the rest the front arb is thought to be sufficient, we can forget about that too; just  leave it.

That leaves to the rear spring rates, arb and ... the dog bones.
Right. Those sub frame spacers. They lower the lower suspension arm mounting point thus lowering the roll centre a bit, which reduces oversteer. Most likely again a cautious move by TRD (with thanks to Beachbum).
Now thís is one we should remember as it may be a very useful one!

So; rear springs and rear arb.
Less roll is very desirable on the MacPherson/Chapman strutted MR. When the outer suspension compresses, the camber changes towards positive, gets positive even and that reduces traction.
Stiffer springs are a good way to have a flatter cornering car but the price is not just a bumpier ride, it is also less compliance, is less traction on real world bumpier roads.
That leaves us the anti roll bar.
The stiffer the arb,  the less roll, but the more tendency to oversteer.
Thus we strive to a flatter car through a stiffer arb but... oversteer.
Now, íf we have not lowered the car so much that the lower suspension arm angle has not lowered the roll centre a lot already, we still have the dog bones up our sleeve to reduce the oversteer a bit while enjoying the benefits of the flatter cornering and having acceptable spring rates. What TRD did minus their light understeer through stiffer front arb.

This is FÚN!
I think I will let this ferment overnight 🙂

[Petrus]

Here an extremely goor article with spreadheets and all.
I can not think of a better explanation of why I am so focussed on the lowering/roll center.
Anyone seriously interested or having handling issues; do read it:

https://edfishjr.com/tag/autocross-porsche-944/

[shnazzle]

Here an extremely goor article with spreadheets and all.
I can not think of a better explanation of why I am so focussed on the lowering/roll center.
Anyone seriously interested or having handling issues; do read it:

https://edfishjr.com/tag/autocross-porsche-944/

Good article but I got to about 30% through and lost the will to live a bit haha.
I'll just stick to trial and error

[Dev]

Taking the damping out of the equasion because asuming that is matching the spring rate, we are left with spring rate and anti roll bars bars.

It stand to reason as a lighthouse that the TRD set up leans towards mild understeer out of legal caution.
That explains the slightly beefed up front arb.

I don't think you can take the damping out of the equation and then compare what the springs and sway bars do on their own.

The TRD front sway bar is not unique for being beefed up. Actually, it was found out a long time ago that a much bigger front sway bar is key to putting down power and therefore there are much larger front sway bar options one in particular was so big  that it was known to bend the end links. 

The rear does not need to be significantly big however it needs the most amount of adjustability so you can achieve mild oversteer at the limit. 

In order to do this you need to start out with suspension that is properly dampened for the roads traveled.  It needs to be soft enough so it doesn't bounce. Having this set up complements  sway bars and works as intended compared to having very high spring rates.
Failing to do this will have the owner do stupid things like delete the rear sway bar because the car is too tail happy.  In a case like this  it is clearly the fault of the struts. 

  This is why most suspension options are suboptimal. If you want to do it right you need to spend the majority of your budget on researched coilovers to set the foundation for what comes next like sway bars and such.

What tends to happen with poor suspension set ups is a loss of traction or unstable behavior which prompts the owner to add wider tires.
Going wide adds more unsprung weight and dulls the drive all the while the main issue with the damping is never addressed just lobotomized.

[Petrus]

Going wide adds more unsprung weight and dulls the drive all the while the main issue with the damping is never addressed just lobotomized.

Hence my investment in lightweight OEM diameter rims and - size rubber fírst.
Well and shedding car weight.

The rest is pending car specifics vs my needs.
Per priciple I do not like anti roll bars, but I also want as soft as possible springs with matched damping. That makes the WhiteLine an attractive option as it offers several settings.
Oh and I do want to maintain ground clearance.
All this on a budget 

Btw., this afternoon had a véry satisfying drive with a gf in the passenger seat. Despite is being a bit too high on the springs and thus it is not very precise, it behaves só neutral on the well warmed up AD08s. Quite a lot of easy to control four wheel drift; the gf noticed and lóve it.
I am getting the hang of avoiding weight transfer to the outside front wheel. That is the big booboo it seems.
Second to avoid, also at the front, is pushing the front in tight corners. Once you have that, you must either ease up and go slower or really lift off to provoke oversteer and thén you can re-balance the car.

Anyway, I am having great fun so priority ONE is not to go backwards from here 

[Dev]

Going wide adds more unsprung weight and dulls the drive all the while the main issue with the damping is never addressed just lobotomized.

Hence my investment in lightweight OEM diameter rims and - size rubber fírst.
Well and shedding car weight.

The rest is pending car specifics vs my needs.
Per priciple I do not like anti roll bars, but I also want as soft as possible springs with matched damping. That makes the WhiteLine an attractive option as it offers several settings.
Oh and I do want to maintain ground clearance.
All this on a budget 

Btw., this afternoon had a véry satisfying drive with a gf in the passenger seat. Despite is being a bit too high on the springs and thus it is not very precise, it behaves só neutral on the well warmed up AD08s. Quite a lot of easy to control four wheel drift; the gf noticed and lóve it.
I am getting the hang of avoiding weight transfer to the outside front wheel. That is the big booboo it seems.
Second to avoid, also at the front, is pushing the front in tight corners. Once you have that, you must either ease up and go slower or really lift off to provoke oversteer and thén you can re-balance the car.

Anyway, I am having great fun so priority ONE is not to go backwards from here 

Thats why I call the accelerator pedal the grip pedal. I work it like a seesaw transferring weight to where it needs it.

I think you should place all of your bets on the KW variant 3.  Its been well designed for this car and double adjustable which will give you so much actual flexibility since you would know how to exploit the settings precisely. 
Other coilovers claim adjustability but they are far away from it when you turn that dial. 

[Petrus]

Don´t want to stretch the budget that far Dev.
The Koni/H&R is at the door under 700€. 
Also, crucial ´detail´, it comes with homologation docs.
Money and the law; two very real world limitations

[Dev]

Don´t want to stretch the budget that far Dev.
The Koni/H&R is at the door under 700€. 
Also, crucial ´detail´, it comes with homologation docs.
Money and the law; two very real world limitations

I bought a car that I parted  out that had that combination of H&R with the Koni inserts.
We added the struts to a friends MR-S and tried them out for a good while and compared it to my suspension.
Its not even half the fun and still poorly done.   We had to turn the damper up to full to get any good road feel but it was too hash at that level over bumps. Its  still much better than the cheap Chinese budget  coilovers like the BCs.  Surprisingly although soft the TRD kit was much better balanced that is because it was done right. The difference between budgeted and premium is one is correct and the other is wrong, and you will be convincing yourself that its ok but will still be exploring other things to fix the main issue and you will never be able to put your finger on the fact that it is the damping which you will never be able to fix.

There comes a time when budget money is a poor value and sometimes there is no substitue for quality.  I would hold off, save up to do it right the first time. The best money for this car is spent on dampers then everything else can be budgeted if need be.

[thetyrant]

KW V3 is the kit I wanted initially for this car after looking at all options out there and would like to try in future, however I wanted to see what could be done at lower budget first hence the koni/tein setup.

I know it limitations especially for track with the soft springs which drop a touch to far for best handling, but for money  (£600 ) it's the best bang for buck option out there for a  mainly road driven car.

I'm hoping whiteline bar's give a notable upgrade enough to rein in spending for little while and just enjoy driving car, later in year I will either convert to adjustable springs or dig deep an get the KW v3, a lot depends on direction I take with car.

[Petrus]

There comes a time when budget money is a poor value and sometimes there is no substitue for quality.  I would hold off, save up to do it right the first time. The best money for this car is spent on dampers then everything else can be budgeted if need be.

I agree, no difference of opinion.
If the KV would come with ABE (EU homologation) then I would go for it in two months; it is only twice the money.
A huge advantage for me is that I can set the springs to give not all that much lowering.
Secondly, the adjustability means I most likely will not need a stiffer rear arb, which makes them ´cheaper´.

As it is, I cannot get it road legal all that easily.
To have it road leal, it must be added to the vehicle doc. For that it must come with at least a homologation on the parts ánd I need a certified workshop declaration of correct fitment. 
I have the question about any EU certification outstanding with a German seller.

Unless there is a homologation possible, it will háve to be Koni/H&R with either 20/20 or 30/30 springs, again depending on the ABE availeble.

[thetyrant]

I thought KW V3 was EU/TUV certified like most of their kits ?   there is a link to a certificate on KW webshop linked below but not sure if this is what you need for your country ?

KW Link - https://www.kwsuspensions.co.uk/shop/TOYOTA_MR_2_III__ZZW3_____10_1999-06_2007__ZZW3__1.8_16V_VT-i__ZZW30__Petrol_103KW_1794ccm_s7U1ELCBsFBccvS0ugBwIg../56/Street_Performance/35256005

Only possible issue for me with the KW kit after speaking to them directly was they expressly said not for track use with premium semi-slick or better tyres, this is due to the amount of lateral load these tyres can generate and they don't feel the internal damper rod bushing that has to deal with these is robust enough to cope longterm when running very sticky tyres on track!, strange they would design it this way but after lengthy discussed with my contact at KW we came to conclusion they should be ok for what I had in mind (road and light track/sprint use with Federal RSR rubber currently), however its a niggle in back of my mind though as they are not cheap things to have break, rebuilding isn't a problem but wouldn't want to have to worry too much about that, I might propose they let me have a set to test/document but don't think that's going to work

[Petrus]

I thought KW V3 was EU/TUV certified like most of their kits ?   there is a link to a certificate on KW webshop linked below but not sure if this is what you need for your country ?

http://docs.kwsuspension.de/ga-KWGFw-2004-ktvpzw-ex-1250_1K.pdf

is the one!! 

Looking at the best offers, the price difference is 1000€ though. Yes, I know, it ís better. Thát much better even.
Just had another spin with a(nother) gf and the car goes éver so nicely. I am already wáy illegal highway speeds through B-road corners    Not sure how much better I wánt it to be