LowRyter

After a week, here's my impressions of the Bilstein B6 replacements. I can only assume at 65k miles my base '08 still had OEM shocks. It rode OK but I noticed that the rear seemed floaty over big bumps.

After test driving it over those bumps the rear is more planted. The ride is firm but still compliant, not a real difference. The one thing I really notice is I seldom get a traction warning on the DIC and the attendant power loss. I'd get that all the time when going around a corner and hitting any rough patch of pavement. Now I can gun it and even get a little power slide in normal ride mode.

I can't recall getting "dead" power interruption going around a corner since I installed the B6s

I am not sure anyone has mentioned this before.

Vette_Fan

That sounds about right. I had Bilstein Sport shocks in my C5 + Hotchkis sway bars & Hotchkis adjustable endlinks.

The car used to slide even at 25 mph going into a turn on OEM set up. Tires were worn, which made the car slide easily. In turns, confidence was low. AFTER the new set up, with same old tires, car was planted all the time. It was flat and I could do an "S" turn as quickly as I could turn the steering, without the car letting itself go. In theory, taction/AH won't come on if the car is not sliding. If the car sticks, those signs don't come on.

With my "new" C6, I am a little uncertain about the exact set up I want. I'm hung on the end -inks I should get to go with my Z51 sway bars. And I have bought the Bilstein shocks + Z06 (F & R) springs. Now, I'm getting conflicting info whether I should change both springs, or the front only, or the rear only...

Vette_Fan

I am making an appointment at a local shop to get the suspension parts replaced. I will be replacing the OEM shocks with B8 Bilstiens, Moog end-links, and Z06 springs in my Base C6.
Question: Should I change both Front & Rear springs, or just the Front or only the rear? Also, please add what difference will it make by doing so..

VETYGUD

This has been answered several times by several people.
For the handling and driving that you are trying to improve on I would not replace the rear spring to a Z06 but keep the stock base spring unless you are going to add a lot more HP and wider rear tires. It is not necessary and can create an imbalance that could cause dangerous handling characteristics. The heavier rear springs are added to support more HP and wider tires because of the higher HP.

I basically have the same setup as you want as described earlier in this thread and it works great for me.

Gryphon_

I suggest watching a few youtube vids on how springs affect understeer/oversteer: the short story is that the stiffer end will slide first. So if you stiffen up the rear and don't change anything else, when you push the car to the limit, it will oversteer (back end will start to slide out).

I have left the stock springs on my 08 C6 (with F55 suspension and brakes) well alone for that reason.

Vette_Fan

New Info -
So now I am being advised to change BOTH (front & rear) Z06 springs. This is throwing me off now, I can't decide which way to go, hence delaying my mods.

Vette_Fan

^ ttt

TxLefty

I've been wondering about some of the parts mixing being suggested. As noted, a stiffer rear spring without compensating changes could result in nasty oversteer at the limit, and that limit might very well be lower than it was stock. A stiffer front spring should help with dive, but it could also serve to increase understeer. IMHO, one is probably better off, unless you really are a suspension tuning guru, to purchase parts that are tuned to work together. There is much less chance of ending up with a package that could cause inferior and possibly dangerous handling characteristics. Have fun. Be safe.

HOXXOH

And the package has to include the tires, since that's the part that connects to the pavement.

HOXXOH

I'm not advising. I'm only telling you what combos are a bad choice. You wouldn't put base tires on a Z06, so why put a Z06 suspension on a base car with base tires? I just don't want to hear that you went over the edge on a mountain curve. Not everything is an upgrade by itself.

Vette_Fan

I hear ya, and I agree. I was just sharing the "new info" I had received. That's why I'm trying to bounce ideas here. Next week I'll, hopefully, be getting these things done.

Final plan is - I'll keep the Z51 sway bars, install Bilstein B8 shocks, install front Z06 spring (which is very similar to the Z51 spring), and Moog end-links. I'll keep the base rear spring, which I'm told is stiffer than Z51 anyway (and not add the Z06 rear spring. Saves a little labor too ). After this, I'll get a 4 wheel alignment. That sounds like a safe bet to me.

I'll drive the car for a couple of weeks to assess its handling, get the alignment checked again. And then return back with feedback and see if there are any other changes needed (hopefully not).

Gryphon_

That's good advice. if you push this car hard around corners you need balanced front and rear springs, period.

HOXXOH

The OP has a base car. Without the correct tires to match the Z06 stiffer springs, he'd slide the car off the road if attempting the same speed of a Z06 and even possibly at a lower speed than a stock base. It's not a balanced approach unless all the components complement each other and the driver understands the limitations.