what to do to improve handling of a F55 car
 

been thinking of ways to improve the ahndling of my F55 car. I am considering starting with at least a bigger front sway bar. As for shocks, is there anything available without loosing the dual ride?
Does anyone have a chart of spring rates for the C6?

Many on the forum put on C6 Z51 Sways front and back:rock:

The rheomagnetic shocks are the F55 suspension. What many of us F55 owners have longed for is an electronic tuning capability like those for LS engines and A6 transmissions.

how about z51 springs?

If you are looking for a bit of flatter cornering with little compromise to ride, switch to Z51 sway bars.

I found a place that sells them, they offer either the Z51 or the Z06. Which would be the better choice?

I forgot to ask, what year is your car?

Under normal circumstances, my prediction would be that you will be happier with the Z51.

Here is a table of the spring rates and sway bar diameters. The Z51 will neutralize the understeer to adding a slight bit of oversteer. The Z06 bars with the F55 shocks will add a fair bit more oversteer.

http://img.photobucket.com/albums/v6...gs_comp-vi.jpg

Just a suggestion: A better investment for the long term would be your attendance at a good driving school. You may find that improving your driving skill may trump throwing money at suspension parts.

That said, many C6 owners have installed Z51 sways, front and rear. Do both, since just doing the front will result in a bit too much oversteer.

I have the F55 with Z51 sway bars (front & rear). A very worthwhile mod if you ask me. :yesnod:

As others already mentioned .. a set of Z51 Sway bars :thumbs:
It depends on how serious you want to get, but I also have F55 suspension and put a set of Z51 Sway bars on.
IMO, it's a Great balanced, all around setup, especially for the street. :cheers:

My 07 F55 coupe has Z06 sways front & rear....Z06 wheels wrapped in Michelin Pilot Sports....& a sturdy insulated tunnel plate. No complaints!

:cheers:

Thanks for the answers,
SanDiegoBert, do you even know my driving skill? I am asking about other's experience with mods to improve the handling of the car so I go in the correct direction. I have been to driving schools and attended 2 years of autoX. I am just new with this particular 2006 vette.

Yup.... I'm going to be doing this soon.

Obviously, I don't. That's why I said it was just a suggestion. I didn't consult your profile. That info is in your profile, right?

I know some guys who keep adding equipment to make them "a better driver". It might make the car handle better, but a driving school graduates better drivers

Relax, man. It was just a suggestion.

I don't think we have any good data on this yet. It is questionable whether the F55 shock can control the Z51 spring. With Z51 sways the F55 is a pretty good autocross car. I have run my car the last 2 years with this setup and have been happy. On a road course though the weak front spring is really bad, to much nose dive to the point IMO of being dangerous. I just had my right front shock fail over the winter and am putting on coil overs instead.

Since the Z51 front spring is much stiffer than the base/F55, it might be easier to "control".
Imagine you had a spring so stiff that it would only move 1/10" even when hitting a huge pothole. Any oscillations would be less than 1/10", and hardly noticable. A wimpy shock might not stop the oscillations immediately, but I think that would work better than the same wimpy shock trying to control a very soft spring that moves 6" every time it hits a little bump.

I have the Z51 suspension on our 2009, but installed base model shocks to soften the ride over the frost-heave-every-thirty-feet roads of Illinois. Of course, the suspension moves around more than with the factory Z51 shocks, but it seems like less movement than on the cars I have driven with the complete base suspension. I'm pretty happy with this combination.

An interesting line of discussion, but perhaps we are hijacking the thread...

Jim I think dampening would be fine I would worry about rebound. But midlifecrisis(?) is getting ready to do just that. Soon we will have some real world experience.

This!

Perhaps overkill for many, but I tore off all my z51 suspension stuff, sold it. Removed leaf springs. Added adjustable coil overs, G1 (heavy as he'll) sway bars/HD adjustable endlinks, bump steer kit etc. It is such a night and day difference. Gone are the high speed wallows reverberating back and forth. No more nose dives upon braking. The car is way more settled and complient. The only downside is on bumpy roads it can be harsh if you run heavy springs. Smooth roads/canyons and the track is ideal for this set up.

The only other set-up (with leaf springs) I found that was remotely close is a friends C6 with Phadt inverted sport shocks and Phadt light weight adjustable sway bars.

I thought F55 Magnetic Ride was like the top of the line. I am looking to get that option on my next Corvette for the safety/road hugging benefit. Are you saying F55 is basically the Base suspension with the Magnetic Shocks/System? Please comment, thanks.

Trade it for a GS?

On the base C6, yes.
On the GS, it's like the normal GS suspension (similar to old Z51) but with the magnetic shocks. A different animal.

what I still want to knw is the spring rates for the f55 setup, mine has the f55 shocks and the FE2 springs, which should be stiffer than the base FE1, as the FE1 is listed as soft ride and the FE2 as Handleing/firm, and FE3 as sport.

Looking forward to his posts!
Thanks.

F55 with a GS just flat out corrners. In sport mode there was no roll or lean that I could detect and the GY Gen 2's bit the road like a raging pitbull.

Love this car!

http://i1015.photobucket.com/albums/...SC_0198_01.jpg

http://i1015.photobucket.com/albums/...SC_0242_01.jpg

Don't put A/S tires on it as it'll make the handling worst especially in tour mode (I had an 08).

I was about to go with Pfadt sways on my 08 and will probably do the same with my 11 eventually.

The road near Jerome is real nice.

I should have this done within the next couple of months. A lot of my HPDE hopes aren't going to materialize this year since I'm just too busy.

I've done four basic things to my 2011 F55: Z51 sways, ride height/rake, poly bushings, and tire pressures.

Gearhead Jim started a thread on ride height a few months back, and through that I found that by rough measurement, the ride height on my vehicle was way higher than that reported by anyone else. Through a series of adjustments and testing, I ended up with an early C6 Z51 spec, which has a lot of downward rake. Over the years, apparently GM has specified a more level ride height for the C6, but I seemed to find that putting the nose down, and presumably the center of gravity, reduced body roll up front and gave me more front end grip. This may be why the early Z51's were known to be so tail happy. With with the stock soft front spring, this reduced the understeer inherent in the spring choice and in combination with higher front tire pressures gave me a very slightly understeering balance.

Despite what the thickness of the Z51 bars might indicate, putting them on didn't really alter handling balance that much. There's WAY less roll, practically none up to 70-80%. I first put them on with the rubber bushings, and all I remember really having to do was to reduce front tire pressures a bit and I got back to that slightly understeering handling balance at the traction limit.

The poly bushings added what felt like 10-15% more roll stiffness but not any more road noise or harshness, but since I'm still running those rock-hard OEM GS-2's, I started losing traction on chatter bumps in mid-corner if I hit them with the outside wheels. It just felt like the tires weren't compliant enough, and these GS-2's have always seemed to take forever to regain traction once they start to slip. Dropping tire pressures helped a bit, as has a month or so to let the bushings break in, but i still have this problem. Admitted, this occurs at pretty high cornering speeds and I'm almost sure this problem will go away when I change tires. The poly bushings have changed the handling balance, since they feel like they've stiffened up the front more than the rear. I have slight to moderate understeer at the limit. More tire pressure up front could help, but then the loss of traction on chatter bumps would be worse. Catch 22, but of course in this situation probably the Z51 front spring is the ideal solution.

Last thing I did was to use the Pfadt aggressive street alignment specs, but to go a little more negative camber up front, to compensate for the softer spring. I'm running zero toe and have very even wear (unfortunately, since I want these tires to wear out so I can swap them).

So, the more I've driven with this configuration, the more I am amazed that someone like TMyers can drive so fast with this mismatched spring rate combo. It is not noticeable up to 70-80%, but above that, and especially in my case where I have a significant downward rake, coming off the brakes lifts the nose and upsets the car balance right at corner entry. Also, each time a change has increased roll stiffness, traction has gone up, but also sensitivity to mid-corner throttle and trail braking has gone up too, so you pay more of a price for hitting a corner with the wrong entry speed. And it is harder at my amateur skill level to recover traction once it is exceeded.

Anyhow, it's good to have had a couple of months in between each of these changes so I can see what exactly happens with each of them. Coming from a lot of HPDE experience in the '90's, I've come to realize that a lot of my traction perceptions are based on how much body roll there is, and now with very little body roll all the time, it's been something else to learn.

if you could post your ride hieghts I would appreciate it.

Jim, thanks for the info! Thought you also got enhanced brakes with base car and F55 as well. Guess suspension stays same. Looks like the GS with F55 is the way to go.

I put the Z51 bars on my 08 F55 vert. The steering is much more precise and it takes the
corners much flatter now. Big improvement.....:)

No, that is why everyone recommends changing to Z51 swaybars if you have F55 and want improved handling rather than Z51 option owners being advised to change to F55 parts. Z51 is no longer available. It was a package of options for performance handling including coolers and gears and improved brakes as well as the sway bars and shocks and springs. It was discontinued when the Grand Sport was introduced.

Yes, F55 is pretty much just magnetic shocks on an otherwise base car. It has an intermediate ride quality between base and Z51 at the expense of intermediate handling.

"state of art" is more like it. Most would equate that with "top of the line". Some of the most expensive supercars use it, you have to be the judge yourself. :D

So that makes a Chevy Volt "top of the line"? :rofl: :cheers:


BTW, the expensive supercars that use it like the ZR1 don't use the same inexpensive parts that the base Corvette has to use to keep the price down. Everything on a car is a compromise.

I had the Z51 sway bars on my 2008 C6 Coupe with F55, and I found that the back end wanted to come around when getting on the gas at corner exit. I have since switched to Johnny O'Connell sway bars from Pfadt and it is a very nice improvement over the Z51 bars - much better balanced and no oversteer when getting on the gas at the apex of the turn.

My recommendation:
Johnny O'Connell sway bars
Lower car all the way on stock lowering bolts
Michelin Pilot Sport PS2 ZP tires
Pfadt performance street alignment

Wade

IMHO the MR suspension is the best 'all-around' suspension offered by Corvette. Before changing to coil-overs for road course performance I used the MR suspension both on the street and the track with a variety of sway bars, tires, and other modifications. Obviously, how you modify the setup of your car depends on how you use it but even in its stock trim the MR suspension is quite capable. Upgrading the sway bars is a logical first step (see below). If you use the car competitively in-time you'll want to get-away from the runflat tires but IMO they're good to learn with. I found the Pfadt control arm bushing kit gave the car a somewhat more responsive feel...a 'lighter' touch if you will.

If you're not already doing so I suggest you enter HPDE courses...start learning to drive on a road course. NASA and SCCA are two other great road course organizations to start with. Even the parking lot autocross events are good experience. Improve your driving skills in a safe environment where, at your own pace, you can explore the true potential of the car. Again, I think it's beneficial to learn using your street tires before going to more of a 'track' tire. I think improving the sway bars is a given with the F55 option....I'd look to do that immediately. Learn what you and your car can do in its stock, street configuraion. There are others mods you can make to improve the handling of your car (for its specific use and purpose) but IMO you'll find your F55 equipped C6 handles quite well even in its stock trim.

With the MR suspension the Z51 sway bars are an improvement over the 'base' sway bars. When the C6 was being developed engineers knew the Z51 sway bars were better with the F55 option but at that time the marketing execs didn't want the MR suspension perceived as any sort of a 'performance' suspension which might compete with their Z51 option (or even with the Z06).

The Z51 sway bars are a modest improvement for a modest price. If you ever plan on changing to wider, Z06 size tires IMO the Z06 sway bars would be the right choice.

I have the F55 package on my 08 coupe. The sport mode is tight enough for me.

:iagree:

For the last 3 years I have been the champ in every class I have run in our clubs autocross series, Novice, Stock and Prepped. The first 2 years running the car totally stock, last year added poly bushings and Z51 sways. As it stands I run close to the fastest cars out there. I am sure that if I had the means to run A6 tires I would challenge for fast time of the day every outing.

Where IMO the fault of the F55 system shows up in on the track and in high speed braking zones. The front spring is just to soft and the dive can be excessive. At one track we drive front straight speeds approach 150mph. At about the 3qtr mark is a 35mph chicane. With my track pads on I swear I could pick the rear end of the ground.

Like Wayne I am moving up to coil overs this year. The primary reason for doing this is a failure of the front right shock. It seems like a good time to make the move. Of course the improvement in handling will be nice. I might even swap system back and forth as the process, not counting the electronics is not hard.

I asked Pfadt

Quote:
Originally Posted by ScottJ03
What do you suggest as far as sway bars for Magnetic Ride, GS - 2012 CE.
Thanks,
Scott
Hey Scott. You've got a couple different options for Mag Ride sway bars. Any of our sway bar options will work just as advertised along with the Mag Ride system without making any changes to the Mag Ride it's self.

If you're occasionally tracking the car casually you should look at our Johnny O'Connell sways. They will offer you a nice increase in performance, and their price point makes them great for street cars. The bars themselves are fixed in the front and have 3 positions of adjustment in the rear.

Your other option is our Heavy Duty - Light Rate sway bars. They will offer overall very similar bar rates to the JO bars, but are adjustable in both the front and rear, and are overall a little lighter than the JO bars are. If you're competing with your car and using street tires this is the best option.

The last sway bar option we have are the Heavy Duty - Heavy Rates. These are the stiffest bars that we manufacture, and are perfectly suited for extreme track use with race tires. With the amounts of grip that are generated with race tires you need large amounts of roll resistance as well, and these are just what you need for that application.

Street Cars - Johnny O'Connell bars are a great balance of price and performance.
Street cars / occasional track cars - Light rates work extremely well, are lightweight and adjustable
Race Cars / Occasional street cars - Heavy Rates are the stiffest bars we offer, best used with race tires.

Let me know if you have any questions Scott! No matter what the application we've got the bars for you.

--
Jarrett

When I had my 05 F55, I put Z51 front/rear sway bars and Z06 springs and it really tightened up the suspension.

Jarrett is a gret guy to work with. I was going to upgrade my Z51 sways to the JOC's this year. But with the coil overs going on that won't be happening.

ZMyers, look into QA1 shocks, I have the double adjustables on my C4 and they are phenomenal. If you go to those you can still remain in the SStock class, if you go to coil overs you will have to move to the mod classes....
I am going to try the Z51 bars alone first, then decide on stiffer springs.

I have been out of stock class since last year. Our club does only Corvettes and the rules are different than any where else I have been.

bummer!!!

Well I ordered the Z51 swaybars with poly bushings from partstaxi. Really awsome sale price if anyone is considering it. the price was really good!!!

The F55 package is definitely a step in the right direction past the base suspension it's built upon... but in the end there are still limitations to ultimate handling with spring rates just as TMeyers pointed out.

If you want to retain your F55 system we do have some products that can help you achieve sportier handling though. The first thing we would recommend are the Johnny O'Connell sway bars. Not only will they increase the overall roll stiffness of the car, but help improve the balance as well. One of the keys to making the Corvette easier to drive is to bring the car closer to neutral handling rather than the oversteer that's present in many situations. The JO bars do exactly this by significantly increasing the front roll stiffness and making the bar package front bar biased. You can expect the car to be more confident at turn in, and easier to control at the limit with the Johnny O'Connell bars.

You can also move to our Poly Control Arm Kit. This will improve the response from your suspension by eliminating some of the deflection from the rubber bushings at the control arms. For cars that see both significant street and track time these are a great upgrade to help improve your cars response.

Past that if you're interested in significantly increasing your Corvettes performance you can move to one of our FeatherLight Generation Single Adjustable coilover packages. They will eliminate the factory leaf spring, as well as address some of the issues that the F55 package can't compensate for. Diving under braking and acceleration will be significantly improved with the increased spring rates on our FeatherLight Generations, this will be most noticeable for folks running race tires on high speed tracks. You will also end up with dampers that were designed specifically for your Corvette, with Corvette specific mounting solutions that keep available suspension articulation and travel at many different ride heights, while keeping deflection and friction to a minimum. You will lose the ability to adjust your ride quality from inside the car, but with the adjustable dampers you will be able to directly control ride quality with the easily accessible adjustment knobs at the bottom of each shock.

There are a ton of different things you can do to your Corvette! That's one thing that makes these cars so great. If you haven't had one already, a performance alignment after you've set your final ride heights are key to keeping your tires happy and performance high. You can find a copy of our alignment guide at the bottom of this product description page here:

Seeing how fast TMeyers was on his Mag Ride setup we're really excited to see how he does during the move to coilovers! :cheers:

http://www.pfadtracing.com/photos/da..._Alignment.jpg

Well the coil overs are here. It is a shame they will be mounted on the car, they look so good new. Anyway I was looking at the instruction and the Pfadt Recommended ride height.

26.4 front
27.3 rear
Measured from the fender arch

I went back and looked at the ride height I am at today.

26.4 Front
27.5 Rear

Fyi I have never lowered or raised my suspension.

Did ya measure BOTH sides of the car?:yesnod:

Yes

I have been running Z06 sways, and front spring on my 07 F55 for years. I have the Z06 rear spring but the car was so improved I did not put it on. Like in some of the earlier posts, the car has more of a downward rake.

For now, chasing more handling would be silly as the stock (junk) tires have 27K on them so traction is very limited. I have the widebody on the back and will be going with nitto invos.

A full track setup cannot be beat but most of us must admit that we drive on the street. The F55 is so very smooth it makes long trips easy. If the streets in Seattle / Philadelphia get any worse we need to start talking about a C6 lift kit.

A word of caution: There were no posts about putting the Z06 spring on when I did it. The spring profile required additional (easy) steps compared to the Z51 spring. If you mess it up, you can tear off the sensors or strip a bolt that holds on the upper A-Arm. Oh..or never get it back into alignment.

Would you please explain what the differences are? I'm going to be putting in one or the other, and it seems like the spring rates are close enough that they might be within manufacturing tolerances, so it might come down to whichever one is cheaper, unless the Z06 sprint takes a lot of extra effort.

Thanks.