Has anyone installed one (such as the one from DRM)? How is it compared to the stock Z06 ride? Harsher?
thanks!

 

I believe John R. " Team ZR1" in your area has Penskes on his Car. He runs in 170 MPH class in open road racing. A very good test. Check his website Team ZR1 and ask..

The best,

John :hat

 

I had a set of ProShock brand Coil Overs installed on my Z - back in the winter ... it was nice, until I bottom'd out the first time, and went back to stock anyway .... just not for me, on these sucky NJ/NY roads. I hardly autocross, well - do more daily driving with the car, so I had no choice in the matter ... ended up getting full credit for the $1300 setup ... breaking even and learning a lot, I guess you can say. I do not recommend them, unless you have a specific reason. They do improved your ride quality on cornering, etc .. but long stretch runs - make no difference, on a good surface !

/rob

 

What was your impression of how the car felt under normal driving conditions with the coil overs as compared to the stock ride?

BTW, I bought the car to autocross and take on the track, as well as drive around for fun, which is why I'm considering it.

thanks

 

Coilovers gotta be better in autocross and road courses, or racing cars wouldn't used them.
Paul

 

Here's the thing - if coilovers are going to rattle my fillings out in day to day driving, then that's not what I want. I'm fully convinced that they're the way to go for the track but I don't want to sacrifice daily driveability.
thanks

 

The advantage of coil overs is:

A) they are adjustable for corner weight.
B) the springs have lower hysteresis loss.

A means that you can get both front and both rear tires to carry the same weight with the driver sitting in the drivers seat.

B means that the suspension can be keep the tires on the road a little bit better over bumps and dips.

Combined with better than stock shocks, you can dial in different compression/rebound settings to aid the drivers style of driving.

 

Would a Coilover suspension (such as DRM) improve 0-60 or 1/4 mile times?

How does it fair with the Vette's Traction Control System?

What do all of you think the handling would be in comparison to a M5 or Ferrari?

Curious - I'm thinking about upgrading to Coilovers.

:cheers:

 

I doubt it.

M5? You're kidding right? And which Ferrari? The 360 Modena is already comparable. Coil overs are for track cars, either road racing or autocross. And they are far easier to screw up than to get right. If you don't have scales and a suspension genius to help you setup the car, stick to the stock ZO6 suspension.

 

Two big questions:

1. Are you now driving at a skill level that the stock suspension is limiting your performance?

2. Are you competing or intending to compete in a class where the competition is utilizing expensive and extensive suspension mods that give them an advantage?

The stock ZO6 spring/sway/shock setup is easily capable of running quicker laps than most anything you will encounter at a driver school, costing less than $75,000, and a few costing much more. Autocross rules will demand you remain pretty stock (no coil overs) unless you want to run an unlimited class against lightweight race cars.

I drive the bejeezus out of my car at drivers schools and have a complete blast passing virtually everything, sometimes twice. I run stock suspension (lowered of course on stock adjusters) including tires, and can outrun most anything, even those with race rubber, I have run across. Unless I were racing, I wouldn't do much more than a set of single adjustable Penske shocks (not coil-overs) and T1 sway bars, plus a set of Hoosier race tires mounted on super-light rims. Might consider a Baer brake kit to top this off, you can never have enough brakes... The springs and spring configuration is not a problem that needs fixing on the car, IMHO. :cheers:

 

Ok, that makes sense. I do not plan to get in to competition racing on the track and #1 has not been achieved yet.

Part of my motivation on upgrading the suspension was just to add improvement on handling. To max out the Vette's structural design maybe?

The Z06's ride is really sweet, sporty and tight - with some exceptions. When I'm taking a tight 45-90 degree turn I will sometimes hit a small road "blemish" (pot hole, etc.) and then notice a slight hop in the rear. Active handling takes care of this should I be going fairly fast.

My thought on fixing this problem was adding in a set of DRM or Penske type Coilovers. Yes, I get a little extreme - but that is how I like it.

What type of swaybar would be the "Best" on the market - esp. in comparision to the stock Z06 system (which is great mind you!).

Thoughts?

I thought the M5 part was funny...

 

Before anyone starts re-engineering the suspension of their Corvette, they should learn the basics of chassis engineering. "How to Make Your Car Handle" by Fred Puhn from Classic Motorbooks is a good place to start. You need to get comfortable with terms such as springs rate, ride rate, ride frequency, roll stiffness, and roll stiffness distribution.

Just blindly substituting components is a great way to screw up the car while burning up a lot of money.

Springs are basically springs whether they are made out of coiled steel wire or molded composite. Mathematically they are modeled the same way. It's the WHEEL RATE they yield that affects ride and handling. Composite springs do have more inherent damping, but this is compensated when selecting the final damping rates, which are the most subjective parameter. They usually have to be set by experimentation and the optimum will change with average speed, average bumpiness of the course, and driver preference. Higher speeds and bumpier courses generally require more rebound damping.

We've had this discussion before, but I will restate. According to SAE papers written by GM engineers, the C5 shock mounts were only designed to take damping loads and bump stop loads. Adding spring loads to them from coilovers creates the potential to overload them, plus you place increased deflection on the side rail due to the higher average loading. Good design practice calls for loads to be distributed over as wide an area as possible, and this is accomplished in the C5 design by taking spring loads through the crossmembers and tranferring them to the side rails through the cross member mounts, which are remote from the shock mounts.

Typical coilovers allow for easily adjustable ride height and have adjustable damping. This is good. but the the spring rates are fixed. How do they affect the wheel rates, and how does this affect the roll stiffness distribution? This is information that a chassis engineer needs to understand in order to create the dynamic response requested by the driver. This is over and above the shock mount loading issue, which is a showstopper IMO unless the mounts are reinforced.

A showroom stock Z06 will generate about 1.0g lateral on a skidpad and transients of over 1.2 g (look at the numbers in the June Road and Track). How many can really use this car to its full potential? You're best to find and thoroughly define the limits of the OEM setup before you begin a wholesale amateur re-engineering of a superbly engineered sports car.

In the meantime there are tuning parameters to optimize like tire pressure, ride height, and static alignment settings.

Duke


[Modified by SWCDuke, 1:12 PM 5/15/2002]

 

SWCDuke,
I agree with basically everything you’re saying. :yesnod: Suspension and chassis deisgn and tuning are VERY sophisticated issues.

However, on the point:

1G IS indeed a lot of cornering capability, but if a car could corner at a maximum of, say, 2Gs than you could make 1.5G turns w/o even braking a sweat (read: while talking on the cell, phone, adjusting your radio and waving that babe you’re passing :D at the same time :cool: )

The wider the handling envelope is the more aggressive we can drive a vehicle while not pushing it to the very edge of it’s limit (risking losing control)
You get my idea ;)



[Modified by EuG, 5:34 PM 5/15/2002]

 

You can count one one hand the number of production cars that will corner at 1g. I've experienced such cornering loads on a racetrack in well set up cars on DOT legal racing tires, and I don't think most people really know what 1g feels like in a steady state sweeper at 90 to 100 MPH. It is INTENSE!!!

Ninety percent of the handling equation is tire adhesion and chassis tuning is done to optimize the tires grip characteristics. To get up into the 1.5g range you need real racing tires - slicks. To get much over this you need downforce.

Once you optimize steady state grip and dynamic response with camber settings and anti-roll bars, you start working on transient response - the way the car behaves on corner entry and exit, and on a production car your basic adjustments for transient response are shock absorbers and toe settings.

A few years ago in Car and Driver, Bob Riley was quoted as saying that ninety percent of setting up a car is "reading" shocks. That's Bob Riley of Riley and Scott - one of North America's premier race car designers.

Duke

 

If you want Coilovers installed well ... call Mallett ... they do/sell them all the time and could probalby point you towards a good shop in your area ...

 

Mike Scribner has a DRM coilover kit for sale. I believe his setup is more streetable than most DRM coilover spring combos.
http://forums.corvetteforum.com/zerothread?id=297937

 

Just to clarify - you can adjust the corner weights with the stock springs, by adjusting ride height at each corner. It's not as easy as with coilovers, but it can be done.

Also, not all coilover setups are the same. Some of the aftermarket companies are selling poorly developed products. DRM have been putting coilovers on Corvettes since the 1980's and know what they are doing.

The springs keep the car off the ground but are less important in suspension tuning than the shocks and swaybars. I have factory T1 springs and swaybars on my car and have been very pleased with them - future upgrades will focus on upgrading shocks and control arm bushings.

 

I am interested in a coilover suspension so I talked to Peter at DRM regarding the issue of shock mounts with a coilover kit. Without going into details, DRM has installed numerous coilover kits. Being close to their shop, whenever I go there I always see several SCCA T1 cars in various stages of development. According to Peter, they have not heard of a single instance of any type of structural or shock break. This comment isn't meant to start flames because I am as concerned as anyone else driving a car at high speed. I also trust DRM not to develop or sell something that could fail and cause injury to someone. BTW, has anyone ever heard that a coilover suspension has broken on a vette?

 

I have to agree with others on here who've noted it best not to overly screw with the millions of $$$ put into engineering the suspension package on a Z06. You will be much better served buying tires regularly + driving schools!!

Here's some further food for thought for you. My new 2002 Z06 has just 1500 miles on her. In getting ready for this season's racing, I took her in for a baseline alignment check. Found that right outta the factory I got REALLY screwed up alignment!! No amount of parts and fancy coilovers is gonna fix that!!

So you might just start by making absolutely sure you tires are at correct pressures. + Your alignment is optimized for track running. The Z06 is amazing in and of itself right out of the box!

 

Agreed .. why mess with stock ... the only change I think would be shocks ... and maybe swaybars ...


[Modified by NewVetteLover, 10:02 PM 5/21/2002]