..during some very agressive driving today. Hit some whoop-de-doos in 3rd during a straight & the car felt a bit floaty. 21k miles on her.

What are you guys with the Z51 setup replacing your shocks with; Bilstein?

Feedback?

 

I'm thinking of "Pfadt Engineering" coil overs. Does anybody have experience with them??

 

Eeek, not ready to invest the bank for COs yet. I'm a bit leery of Bilsteins as my previous experience with them turn the vehicles into very harsh driving vehicles.

 

Ok, on my 2003 ran Bilstein sports. Not rated by Bilstein yet for our vehicles, but have run into many members that switched to them for our C6s, and they fit fine. I bought another set and installed them on this car. They actually seemed to smooth the ride out a bit, were about 25% more stout looking than the stock shocks for Z51's, but provided a rather substantial level of stability in quick transition moves, and over ruff surfaces. I also feel that I can push the car about 5% harder in overall driving. When putting down the road, cant even tell that the shocks are different, only when running the car in the twisties or over ruff roads is it apparent the level of performance increase, and for $300 shipped to my door, was worth every penny.

 

Koni is developing FSD shocks for the C6. Last I heard they were supposed to be released before the end of the year. www.koni-fsd.com

I believe they are also making a sport version for the C6 as well.

There's a guy who works at Koni that posts on here. Maybe he can give us an update on the C6 shocks?

 

Here in the Midwest where the roads are not always smooth, I think that the stock Z51 shocks may be about right. I agree that a series of roller coaster dips can make the car a bit floaty, but it also seems to do a very good job with pavement irregularities in a corner.
My feeling is that tighter shocks may make the car feel more under control in some circumstances but more skittish in others.
We had Bilstein Sports on our Z51 C5 but so far we've stayed with the stock Z51 shocks on the C6.
Your mileage, your roads, and your personal taste; may differ.

 

I have the bilstein sports and while they were rough at first, the improvment in handling was worth it. Over time, I have noticed two things; the car doesnt have wheel hop anymore and the ride softened up to a controlled finesse that doesnt bounce like the stock Z51 shocks did. www.eshocks.com 299 free shipping.

 

 

For those that installed the Bilsteins, what was your milage when you made the swap?

Thanks.

 

Yes, we will have two flavors to choose from on C5/C6 shocks by the end of this year:

1. An autocross/track days adjustable damping, monotube Sport shock with inverted bodies and tuning ports accessible without removing wheels from the car.
2. An FSD shock, which deals much better than what we have seen on the market today from a ride quality point of view, yet also does a nice job of body control as well. I did the before/after ride on the prototype shocks using a C6/Z51;I expected the taut body motion control, but was amazed at the ride improvement over coarse/uneven surfaces, where the OE setup required a lot of steering correction to stay on-course. Big improvement.

So, you get a choice: Street usage with occasional autocross/track duty = KONI Sports, where mainly daily driver usage = FSDs.

 

I put C6 Z06 shocks on my Z51 and do notice some difference in firmness and a slight increase in harshness. The ride is still not too harsh. I also notice an increase in the "freeway hop" occillation(where the ride of cars with firm suspensions get more jittery(busy) due to the constant subtle rises and falls in elevation on certain concrete roads).

The car does not drive totally different but the increase in firmness is good enough for me. I never tried Bilsteins but they may have a little less float than the C6 Z06 shocks. However, IMO the good thing about the C6 Z06 shocks is that they handle bumpy curves hardly any worse than the Z51 shocks. I wouldn't be surprised if the C6 Z06 shocks have characteristics very similar to the 04 C5 Z06 shocks.

 

Don't confuse road undulations with the car being "floaty." The car may have very well been tracking the road surface accurately. If the road has a series of swells in it, the car will track them.

I've found Z51 to be nice and firm and well-damped, with almost no float on any road surface, other than the time I <cough> may have gotten it a bit airborne...

 

I did the same thing. When I replaced the Z51 shocks, I tried to time the rebound between C6 Z06 and Z51. The C6 Z06 shocks took about twice as long (approx 3 secs to 1.5 secs respectfully) from full compression to full extension, which is better control. I noticed the car handled harsh impacts like speed bumps much better (less kick back)and seems to have less body roll when initially throwing it into a corner.

 

No, this was definitely floaty, which I would qualify as a lack of low-speed rebound damping.

What are 'FSD' shocks?

 

www.koni-fsd.com has an explanation.

 

Frequency Selective Damping shocks are a patented, unique solution to the ride/handling issues often found on today's performance cars.

On the one hand, we want taut body control. On the other, we don't want to feel the harshness of every tar strip, spalled concrete surface or patched asphalt pavement.

Typically, to get one (handling), you trade off the other (ride), but FSD is designed to excell at both, through a parallel-valve mechanical damping system. The main valve deals with body frequency motions (around 1-2 Hz) while the other works on wheel frequencies (10-14 Hz). Most shocks (including KONI's other varieties) are velocity-sensitive rather than frequency-sensitive.

Yes, the Delphi MR electronic system also adjusts damping to optimize ride/handling, but you pay $1750 or so for that option, where the FSD shocks will be priced considerably less and can be fitted to non-MR cars to acheive similar benefits with a simpler system.

We won't have these for the C5/C6 Vettes until the end of this year. Interestingly, these were designed mainly for ride improvement, but some of the Mini guys who are using FSDs report improved autocross performance, probably as they don't have the tendency to over-drive the car with less high-frequency road inputs.

 

I am running the Pfadt Coilovers and adjustable sways from Aaron.

I really like them. I had the Z51 suspension and I noticed mid-corner bumps would make the suspension jump, which was a little disconcerting for my driving style.

I am still tuning the settings, right now I am running full stiff on the front sway, position 2 of 4 on the rear sway, position 10 of 16 on the front coilovers and position 8 of 16 on the rear coilovers.

I am trying to get a fairly neutral balance on mid-corner and exit.
My tire pressures are 34 hot across all 4. I'm going to try lower the rear tires 1 or 2 psi and lowering the rear coilover to 7 and see how that feels.

By the way this is my daily driver and I commute 150miles a day!!

If you set the coilovers down to 4,5 or 6 its totally comfy - so you can definitely live with these coilovers on a daily driver

 

I would jump on a group buy to try Koni FSDs out. Can't wait!

 

I'd seriously consider that as well....
- Ray
Still less than 2,000 miles on my 2007 - and not dissatisfied, but....

 

He's not confused. The Z51 is not well damped at all, IMO. Mine is worse than my '86 Camaro was w/Koni's all around. I noticed the first day I owned my C6/Z51 that it had a dissapointing case of what I simply call; The "Whoopdi-whoops". -Which is what the rear of the car does for a couple cycles after being upset by a bump. I can't wait for FSD's either and I hope they deliver on their promise.