Suspension dilemma. Need advice.

[aj1001]

Hi Gang,

I got my new suspension installed (GMG Racing springs (Eibach) + Bilstein B8 shocks). I really like the look, how the bumps are handled and the firmness.
However, my kids are complaining about headaches... (I bought the S4 instead of S5 because of the kids - so that is an important factor)

I would not characterize the ride as harsh. It's actually pretty good.
What seems to be the issue is what I would call "oscillation" (not sure if that is the right term). You feel the road undulations in your gut - nowhere else. The steering is smooth. When resting your hand on the shifter, that is smooth too.

I got the GMG Racing springs because I was familiar with Eibachs in the past and liked how they handled.

Could this be a case of the springs and shocks don't match?

I have a few options I guess:

Leave it as is and hope they will adapt
Go back to stock and sell the parts (stock is too soft for me...)
Go back to stock and add Eurocode USS and Aleu Kreutz in hopes to have better dynamics
Change the springs to H&R OE or Sports
Bite the bullet and get PSS10s (would have to delay AWE exhaust...)
Another option I haven't considered...


What would you guys do?

Thanks!

[9Schnell]

Ride in back with one of your kids and see if the suspension is rough or there's a funny smell/lack of ventilation for them. Could be as easy as new car scent or even the smell from whatever detailer you use.
Good luck!

[Greedo]

Sell the kids. Problem solved.

[helix139]

Hi Gang,

I got my new suspension installed (GMG Racing springs (Eibach) + Bilstein B8 shocks). I really like the look, how the bumps are handled and the firmness.
However, my kids are complaining about headaches... (I bought the S4 instead of S5 because of the kids - so that is an important factor)

I would not characterize the ride as harsh. It's actually pretty good.
What seems to be the issue is what I would call "oscillation" (not sure if that is the right term). You feel the road undulations in your gut - nowhere else. The steering is smooth. When resting your hand on the shifter, that is smooth too.

I got the GMG Racing springs because I was familiar with Eibachs in the past and liked how they handled.

Could this be a case of the springs and shocks don't match?

I have a few options I guess:

Leave it as is and hope they will adapt
Go back to stock and sell the parts (stock is too soft for me...)
Go back to stock and add Eurocode USS and Aleu Kreutz in hopes to have better dynamics
Change the springs to H&R OE or Sports
Bite the bullet and get PSS10s (would have to delay AWE exhaust...)
Another option I haven't considered...


What would you guys do?

Thanks!

Why specifically did you put the springs and dampers on there in the first place? Did you feel there was too much body roll? too much squat or nose dive? looks?

The problem with upgrading suspension is you really need a plan of what you are trying to achieve. Just replacing components without knowing how they interact with each other can produce worse results than stock suspension. From what it sounds like, you don't have enough damping for your spring rate (which is firmer by nature of being shorter and leaving you with less travel), leading to an underdamped suituation. Both the spring and the shock were likely designed for their stock counterpart. You've also probably introduced some alignment issues since you can't adjust camber on the front tires when you lower it.

My advice would be to add the USS and Alu Kreuz regardless. I think you'd be wise to either go back to the stock spring and damper setup and see how you like that with the eurocode add-ons, and if you still find undesirable suspension characteristics, then work to address them.

[AKPS4]

I think i had a similar problem in my camaro. the shocks were set too stiff and it felt like i was riding in oval wheels. try softening the shocks a bit if you can and see if that helps.

[mkato13]

Sell the kids. Problem solved.

hahaha. Nice!

I went with HR OE sport springs when I added the Ecode sways, drop links and ALU kruz and I love it. SLightly harsher then I wanted but not bad at all.

[aj1001]

Why specifically did you put the springs and dampers on there in the first place? Did you feel there was too much body roll? too much squat or nose dive? looks?

The problem with upgrading suspension is you really need a plan of what you are trying to achieve. Just replacing components without knowing how they interact with each other can produce worse results than stock suspension. From what it sounds like, you don't have enough damping for your spring rate (which is firmer by nature of being shorter and leaving you with less travel), leading to an underdamped suituation. Both the spring and the shock were likely designed for their stock counterpart. You've also probably introduced some alignment issues since you can't adjust camber on the front tires when you lower it.

My advice would be to add the USS and Alu Kreuz regardless. I think you'd be wise to either go back to the stock spring and damper setup and see how you like that with the eurocode add-ons, and if you still find undesirable suspension characteristics, then work to address them.

Good question.
My objective was two fold:
1. I wanted a slightly firmer ride and less body roll.
2. I wanted a more aggressive look.

I specifically didn't go with the stock shocks because I worried that they might be mismatched with the new springs. I gambled that the springs and bilstein shocks would work well together.

[aj1001]

Sell the kids. Problem solved.

With normal kids, I would agree. But these ones are pretty awesome [:d]