kit cat

iTrader: (6)

A lot of us have lowered our GS.
And a lot of us daily driver our GS (or so I assume).

Mine's pretty much all the way down on my coilovers without any correction to the suspension geometry except for the alignment...which is barely within factory spec except for camber. Which means less contact patch, less mu, worse handling as a dd...which is starting to get annoying.

The RCA block is one way to gain more suspension travel and somewhat fix the geometry of our lower control arm BUT at the cost of pushing up our upper control arm.

The S16 chassis is notorious for the front upper arm hitting the top of the wheel. Some people on VSC has cut a hole to let the upper control arm escape... which scares me.

If anyone knows any solution to this, post'em up!!

CK6Speed

iTrader: (1)

At least to regain some full suspension travel you might want to get coilovers that adjust the ride height independently from the spring preload and retains full suspension travel at any height. I believe some of the types that do that is Megan, Stance, and Fortune Auto that I have as well as many others. That, along with the RCAs could give you a good balance of low ride height, full suspension travel, and adequate upper A arm clearance. You also might have to bite the bullet and get higher spring rate springs as well

Either way IMHO if you are too low you wont get that performance back. I was once told that you want to get the Roll Center at ground level. If you go below ground level (Too low) you sacrifice handling just as well. The RCA (Roll Center Adaptors) are supposed to get that roll center closer to ground level without altering the suspension geometry too much. No matter what it will be a compromise as you will never get back to "Like Stock" conditions and I don't really think you'd want to anyway. Well, except for maybe the suspension clearance and alignment specs. Just my 2 cents.

[ant]

my UCA doesnt hit much at all, and i'm on Insurance Group coilovers which only have 10k / 6k spring rates but are base height adjustable and damper adjustable. i am happy with the ride and travel, my car is a daily and seems ok really. it is about 100mm from the ground to the stock bodywork, around 80ishmm to lowest point of exhaust on 19s.

ive had my alignment done, have around -2 camber all round. it handles much better than stock and if i wasnt so careful due to the stretched tyres i run, i reckon i could throw it around a fair bit more than i do.

kit cat

iTrader: (6)

If it wasn't for the cost of getting new coilovers, I would love to get the ones you could adjust the ride height independently . I love my HKS coilovers but that is one feature I wish it had. But good advice, I didn't think about that for some reason.

I don't care how firm my springs have to be (to a certain extent). But with stiffer springs, RCA, and if I can afford it (and probably the most costly and effective), a different set of coilovers.

Maybe it is time for me to bite the bullet and get RCA blocks and roll fenders...-2.6 is too much camber for me.

sam430

iTrader: (10)

Get the RCA from exact. They may not have any in stock though. I will be getting the rear as soon as it becomes available. For some reason, my transmission doesn't like to be leaning forward a bit (thinking it's going downhill - causing to downshift unecessarily. Could be remedied by re-adjusting or resetting zero point on yaw sensor).

Alexus_300

iTrader: (4)

While I have no experience with HKS or tein coilovers, throughout my years of testing coilovers for D2 racing, I've always loved the design of how they have their spring load and height adjustment seperately. I do not agree with people who says to go with a stiffer spring rate to reduce shock travel. If you've ever put sensors on your car and hit the track, you'll notice that a higher spring rate will give you the feeling of less body roll. But the truth is that when you have too stiff of a spring rate, you're loosing contact with the road since your suspension has less modulation. I for one am fortunate that D2 has allowed me to use everything they have to setup all of my cars throughout the years and I feel that the custom spring rate and valving that I have in my GS300 now provides the best ride and handling for the money. Also to address the question about suspension geometry while beeing slammed, I say that it gets more interesting here. I have done alot of research with plenty of engineers about the 2GS suspension geometry. The car is design to be dropped a maximum of around 1.75" in the front and 2" in the rear before you are off of factory spec aligment. When going lower, in order for you to keep your factory suspension aligment spec, you're going to have to shorten your lower control arms and other suspension brace. That's why we have companies like Ikea that makes custom lower control arms.

[ant]

^ lots of companies coilovers now have separate height and pre-load, its pretty much the standard these days except on coilovers designed solely for comfort where they dont expect much height adjustment to be needed (more like an upgraded spring/shock that happens to be slightly height adjustable)

i am a little confused with the fascination with keeping suspension within 'factory spec'. at the end of the day, suspension is a personal preferance thing. the factory spec probably works well with all parameters factory, but once you get real low and big wheels etc it is possible that factory spec is no longer the best anyway. and it also depends how you drive. So its simply a matter of deciding what you dont like about the car, researching how this characteristic of handling/ride is improved, and then going from there to rectify it by whatever arms/componentry is needed.

also on the high spring rates thing, i dont think that most people with Aristos/GS's get high rates for the handling/body roll side of it, they get them so the car doesnt travel so much and thus lifts itself over bumps, inclines, driveways etc without bottoming out. Even with damper adjustability, you cant get the same stiffness as you can through higher rated springs. of course there is a limit, and preload can be adjusted, but still the higher rates combined with damper adjustment can be a good way to get a nice ride whilst maintaining ground clearance.

i really think base adjustable coils are a must on these cars if you are really getting low on big wheels.

GSteg

iTrader: (15)

You took the words right out of my mouth! Not sure why anyone would even want to go back to factory spec unless they want to increase the life of the tires (sometimes factory is less optimal for tire wear). I hope no one is thinking of dropping $2000+ on suspension only to stick to factory spec because they're just that...specs for stock cars.

Now even if you have adjustable upper and lower control arms..what are you going to do with them? Most would shoot for OEM geometry but that's just going backwards. In order to modify your suspension for the right geometry, you need to know how you want your suspension to respond in certain cases. I dont think we can ever 'correct' our suspension just because we dont have access to tools that would develop a geometry for us. I suppose if we were really serious about it, we'd need the help of Penske or Ohlins, but then again if we're serious, we probably wouldn't have picked a GS in the first place

kit cat

iTrader: (6)

I really could care less about putting my suspension geometry within factory spec but I want my alignment to be close to it. I'm running -2.6 of camber now and seeing the inside of the tires wear makes me worry when I think that I only have that much contact patch instead of using the entire width of the wheel (toe and caster are within factory spec).

As for shock travel, I don't see why I would want to limit the travel of a suspension...if a shock is meant to move, why limit it? I'm a suspension noob so just curious. Feel free to shed me some light here.

CK6Speed

iTrader: (1)

I actually agree with that. I myself an running 13kg front and 9 kg rear on my GS430. Seems to work well for a daily driver.

chrispy

iTrader: (21)

When your car is slammed, maybe with a body kit, it might hit the ground on dips and stuff if you have too much suspension travel. Otherwise, I'm not too sure.

GSteg

iTrader: (15)

Coco, I think your best bet right now is to get a set of RCAs. More suspension travel is only bad if your springs aren't stiff enough, and it's causing your tires to rub, or the upper control arm to hit the fender liner.

MJImport

iTrader: (1)

Alexus 300, when you say a 2" drop would not prevent you from adjusting back to factory, do you mean the toe? or camber also? I dropped my gs on Tein SS and its as high as it will go (about 1.25 to 1.5") and it is well beyond factory spec. Maybe the shop I took it to don't know shat.

kit cat

iTrader: (6)

which is why I'm aero-less. not to mention i can't afford it now

i could care less if i rub here and there. but yeah, i guess I do have to limit the travel if I want to go low...

i guess i cant have one's cake and eat it too....

Alexus_300

iTrader: (4)

I know from experimenting and testing with D2 racing coilover throughout the years that this spring rate is very very well adapted to the weight of our GS. I personally run a custom 12.7kg/mm front and 9.3 kg/mm rear with custom valving that is setup and designed by my friend who is a vehicle dynamics engineer for RCR. He's had my car on a 7 post rig in which we tested every single setup available to me from D2 Racing. Also, if you ever get a chance to corner weight your car, do it.... This is the best thing that you could ever do if you were to track your car.