Just installed a set of D2's with the recommended 8/6 spring rates. This replaced my previous setup of CMS springs with GR-2's. The ride is now MUCH stiffer... allowing me to feel every ..... and I mean EVERY bump/imperfection in the road. Even on the softest setting... the ride is still terrible. Living in Toronto, Ontario... our roads are pretty bad. There are small and large bumps/imperfections everywhere.

What I need the expert opinion on is:
What is the softest spring rate I can install without any problems/issues?
By problems... I am reffering to safety issues. I know that performance will be sacrificed with comfort, but with the current setup... Im taking onramps that I previously took at 60km/h at about 120km/h, so loss of performance is not that much of an issue when considering comfort (daily driver). I have been told that the weight of a 4th gen would cause safety issues if a softer spring rate were to be used. I believe (with stiffer settings) the shocks on the D2's will be more than adequate to compensate for the lower spring rates. I have done alot of research and can't seem to come up with an informative answer. Considering D2 offers 3.5, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19 and 21kg ratings on their site, Im assuming that softer rates would not be an issue.

I would like to get down to 6/5.

 

canuck rates are 2.2 f and 5.7 r (kg/mm) and are progressive.
6/5 is much more streetable.

 

Changing the springs probably wont run you cheap. Why did you change to coilovers anyway?

 

Give it a couple weeks and get the dampening right. I would try that first.

 

Coilovers are probably the firmest riding setups you can put in your car. They are geared twards performance, not comfort.

If your looking for a more compliant ride, go back to a spring & strut combo.
Stock springs, combined with a nice performance strut would be your best bet if you can live with the ride height. H&R's with Illuminas and 16" wheels and tires will yield you a very nice ride on a lowered setup.

 

It'll be like $200 and change.

And coilovers are better.

 

I bought the coilovers for both handling and height adjustability (raise the car up for the snow filled winters we get here). As for the comfort level... you would think that a true coilover setup with the right springs would provide for both a performance and comfort level better than... or at least equal to the CMS/GR-2 setup I previously had!?

Im riding on 235/45/17 and want to have the eliminated wheel gap while still maintaining a somewhat descent ride which pointed me towards the D2's as full suspension travel is independant of ride height.

As for adjusting the dampening... iis at the point where the highest vs the lowest setting takes it from a shiity ride to a slightly less shiitier ride.

The most important thing for me is whether the 6/5 or possibly even the 5/3.5 would cause any issues such as SEVERE performance loss or even safety concerns I should be aware of... considering the weight (and distribution) of the 4th gen.

 

i have 9/7 on my car with d2's, boy are they stiff. But when i know i can take corners like no other, doesn't really bother me much although it does take getting used to. I would go with 7/5 to be the softest, and as far as setting the dampening to the softest, make sure that you have it set up so there's more of an oversteer even though it might be a lil bit harder. I can tell you is that those srpings don't become softer with time, at least not with my 9/7 setup. But i've heard that 7/5 feels like stock springs, i'm not so sure about that, but thats what i've heard from other orgers on here.

 

to my knowledge, nobody has had any experience with these spring rates the best person to talk to is your D2 dealer. I have D2s with a 9/7 spring rate and I live in NY so I feel your pain!!

 

To both ImmaSquashYou and MidniteMaxSE ... You 2 are probably the best to understand my situation as I can imagine the roads in NJ and NY are probably as bad as the pothole filled.... than terribly repaired roads of Toronto.


As for my dealer... he has suggested I do some more research into the spring rates before I decide to change them. He has warned of dangers in softer spring rates and has recommended that I shouldn't go any softer than the 8/6 setup. Thats pretty much why I started this thread...

Right now .... those 5/3.5 sound oh so tempting

 

D2 told me that I can go up or down 2kg without having to revalve the struts, which means that you can go down to 6/4 without having to send them your whole suspension setup.......What dangers did they tell you of?

 

You don't want to go too low because there might not be enough travel in the shock, and you might bottom out. That's one potential danger (not sure if it's an issue in this case or not).

 

i'd honestly say just stick it out and get used to the riding. IT IS VERY uncomfortable at first. But i use my i-30 as a daily driver, n the bumps don't bother me really anymore, just feels like my car popped something off everytime i hit a big bump. I had always debated about switching to softer springs since it is my daily driver, but then i figured, since i drive so much, the car's gonna die in like 3 years. which puts me well over 200K, i know that they can last very long, but once the tranny's gone, so is the car. Back to the point, you WILL get used to it, you will get very cautious of every bump you see, and you will remember what lane to pick everyday. Also, you'll see how your taxes are being used since you'll know if a pot hole had been fixed or not. One thing maybe NOT to do is let anyone that gets car sick easily to ride in your car..-= )

 

Coilovers are not a great choice for a street care that weighs 3000+ pounds. Running near stock springs rates is not possible for coilovers because the spring diameter is much narrower than stock. This means that the spring rate has to much stiffer to prevent binding under load -- meaning the individual turns of the coil touch each other.

If you get binding from running too soft a spring, you will get HEAVY understeer on the front suspension

If coilover product makers came out with a 4" diameter version of springs/shocks instead of the usual 3.125" spring diameter, coilovers would be so much more practical for daily driving as the spring rates could be much softer while still allowing for the advantage of ride height adjustability.

 

Well.... swapped the 8/6's for 6/5's and MANNNNNNNNNN..... what a difference!!!

I mean..... this is what an $800 suspension setup is suppose to feel like! Much smoother than my previous setup. No more feeling EVERY SINGLE imperfection in the road. Would never dream of stock..... but its close enough! Still take corners like a champ.... and am dropped nearly 3" front and back. Only bumps I really feel are the BIG *** (2+ inch fackers that are a sorry excuse for a pothole repair) ones in the road.

Any Canadian's looking for more of a streetable setup when purchasing D2's.... I HIGHLY recommend a 6/5 combo to deal with our crippled roads.

Thanks all for the replys and recos.

Just gotta say again..... what a difference.....

 

wow, 6/5 seem too soft?? and should yur handling be less aggressive? Should have got the Basic TEINS, their spring rates also around 6/5 too, good for daily driver but not for autocross. TEINS are nations known for performance and durability.

 

i have the k-sport, and at first it rode liek complete crap......but i kept on adjusting my pre load, and dampening, and decided to get new axles. Damn now this car feels like stock, unless i hit a large hole, or bumps. BUt the ride is very very good now.

it is 10x's better than when i had s-tech/agx........trying plaing around with your settings after you coilovers set