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Handling improvment

5.1K views 36 replies 16 participants last post by  IVOZ06  
#1 ·
I like how my Z06 handles, its the first car i ever own or drive that pushes handling limits this way. I am looking for basic upgrades to my car to make it handle a little better and stop a little better without sacrificing much. I do not go to a track, the car is driven on the street most times. I would like something that i can noticeable handle. Ideally this is what i would want:
1- better braking
2- feel that the car is firmer on the road
3- lower body roll even more
4- high speed stability
5- moderate speed handling capabilites increases. (40-120mphs) not very hard turns but long ones
6- no squeaks rattles.. i dont mind having a firmer maybe stiffer ride if the sacrifice is not that big

Please give me a total package that would work great with each other. i amlooking towards spending around 1200 without installation charges. I would like to see a drastic improvment otherwise i will just change the shocks and pretend i never wanted to upgrade the suspension.

thanks
hassan
 
#2 ·
Start by buying the LAPD $200 or VNM chassis plate or make your own for under $100. In any case, this will lock down the car unlike anything you can imagine doing for $200 or less. I can cloverleaf about 10-15 mph faster than I could before I did this change.

I bought 43" x 12" plate (T6 1/4" alum plate) for $71 and traced out my stock plate, then had it cut and the 36 holes drilled out. It was definitely worth it.
 
#3 ·
TeamSpeed said:
Start by buying the LAPD $200 or VNM chassis plate or make your own for under $100. In any case, this will lock down the car unlike anything you can imagine doing for $200 or less. I can cloverleaf about 10-15 mph faster than I could before I did this change.

I bought 43" x 12" plate (T6 1/4" alum plate) for $71 and traced out my stock plate, then had it cut and the 36 holes drilled out. It was definitely worth it.
I dont know what a VNM chassis plate.. i am a novice in track setups and handling .. i would appreciate an explanation here. BTW what is cloverleaf?

Thanks
 
#5 ·
LAPD sells a chassis reinforcement plate, VNM calls it the backbone, but what they both offer is a better-than-factory plate that is thicker and doesn't flex like the factory one. If you are ever under your car, you will notice that above the exhaust under the floorboards, there is a plate that connects the two sides of the drive tunnel together. It is very flimsy, and these 2 vendors offer a 1/8" stainless steel, and 1/4" aluminum replacement. Once you replace this with these better plates, the car has a pretty good reduction in flex, your car will track better, and it seems to stick to the road better too.

Here is one pic:
http://www.thelapd.com/Merchant2/me...nt.mvc?Screen=PROD&Product_Code=LAPDCFS-01CNC&Category_Code=&Store_Code=thelapd

Cloverleafs are the wonderful design of exits around the midwest, all exits are tight turns shaped like a 4-leaf clover. The trick is to see what the top-speed you can hit on these, I am pretty wimpy, I hit around 60 on them, others are way more daring than I.
 
#6 ·
Upgrades

The brakes and suspension can be upgraded very easily:

Brakes:
- Have the rotors slotted and then Cryo'd
- Race pads, KFP Gold are my preference
- Race Fluid, either Motul 600 or AP 600
- Goodridge SS Lines with AN connectors
- DR SS Caliper Pistons
- Speedbleeders
- DR brake duct Extension
- Either LG Motorsports or Phoenix Caliper duct
- Duct Water Injection (for serious track use only)

Suspension (2 options):
1. Mild improvement
- Lower to factory recommendations
- Aggressive street alignment
- Either OEM '04 or Koni 28 Series shocks
- T1 Front & Rear Bars
2. Maximum Improvement
- Lower past factory recommendations
- Hardbar Rear Lowering Bolts
- Hardbar Front Spring Perch Bolts with Delrin bushings
- VB&P PolyGraphite Bushings
- Hardbar Camber Plate(s)
- Penske DA Shocks with Remote Reservoirs
- Competition Alignment with Corner weighting
- T1 Front & Rear Sway bars
- VB&P Extreme Springs
- Race Tires & Wheels
 
#8 ·
It is a great idea. It does stiffen the chassis. And should be included in the start or basis for building a better handling car

I just do not consider it part of the suspension. However I do group it as a chassis stiffener as I do a harness bar, roll bar or roll cage.

Another thing to consider is that if it adds weight, it adds it low which can be a good thing.

This was an upgrade on the C6. It was not incorporated into the C6 because it was necessarily needed but rather as a standardization of parts considering the C6 Z06. It will be needed on the C6 Z06 as it will use an Aluminum hydroformed frame. Note that Chevy has applied for a patent for hydroforming Aluminum and that it has just produced 3000 Aluminum frames and have built up 11 as test mules so far. These thicker plates will be needed on C6 Z06 to critically stiffen the Aluminum frame. I suspect that they will soon find out that additional gussets are also needed for competition on these frames.
 
#9 ·
DJWorm said:
Suspension (2 options):
1. Mild improvement
- Lower to factory recommendations
- Aggressive street alignment
- Either OEM '04 or Koni 28 Series shocks
- T1 Front & Rear Bars
DJWorm, was this meant to be considered acceptable for a street setup? I've read that some feel T1's would generate more load than the stock supercar sidewalls can handle making them less desirable for the street. If so, would something like NittoR2's stiffer sidewall provide better stability before loss of adhesion?
 
#10 · (Edited)
My suggestions were progressive and prioritized.

IE. You do Step #1 and try it out if you need more then on to step#2.

Notice that the T1 bars are the last thing to do in the mildly agressive street set up. They are also the last thing you would attempt on a race set up.

The T1 bars do not generate more side loads on the GY F1 SC, in fact they would reduce it. What you may be refering to is that with the T1 bars you may be able to corner faster so that the tires would begin to "roll" or possibly "push" . If that is the case then you would increase negative camber and possibly air pressure, depending what the tire pyrometer said..

I have no experience with the Nitto's
 
#11 ·
No. 1 handling improver is seat time.

Every time I think I want to mod my car, I remind myself that I am far from driving the car at its limits the way it is. The day my DE instructor says "how would you like to instruct?", I will begin the mods. Until then it's seat time.

:usa:
 
#12 ·
DJ - a couple of questions/comments re your post:

1. Brakes: Have done the Goodridge SS lines but used ATE fluid. Your opinion of ATE? I am looking hard at the VBP Xtreme ThermoDuric 2 Piece front rotors. They claim that these rotors are 2.66 lbs lighter (each) than stock fronts saving a bit of unsprung weight, are slotted and are treated to deep -300 degree cryogenic cycling. Do you have any experience with/knowledge of these pieces?

2. Comment - I installed the LAPD tunnel stiffner, '04 shocks, and went to the following alignment: Front camber -1.2, caster 7.0, toe 0, rear camber -1.0, rear toe 1/32 toe in. Car seems to handle very noticeably better. Alignment was for street with some track time - do you think this alignment set-up is ok?

3. Your comment re the hydroformed aluminum frame seems to indicate that GM will substantially raise the price of Z06 entry to at least the high $60's? This seems especially true if they are planning on a run of 3,000 or so Z's. Also, I would think the aluminum frame rails will need to be substantially "beefier" than their steel counterparts since aluminum is not as strong as steel. Agree?

Thanks!

:cool:
 
#13 ·
Not that you asked me, but... :D

I think those alignment settings are a decent compromise for an agressive street setup.

Before I had my car totally prepped for SCCA T1, I bought and had a set of T1 sway bars put on with everything else stock except for lowering 3/4" and a more aggressive alignment than you are looking at.

I did a DE at Portland with Kumho Ecsta MX in front and the stock F1SCs in the rear. I thought the car handled better than it did stock, with body roll noticibly reduced. I was keeping up with and passing guys on Hoosier tires, so the setup couldn't have been all bad. Wasn't passed all day.

My only complaint with the T1 bars on the street is that the metal to metal endlinks creak and groan. I've read that you can use other endlinks that don't have this problem.
:cheers:
 
#14 ·
Subdriver said:
Not that you asked me, but... :D

I think those alignment settings are a decent compromise for an agressive street setup.

Before I had my car totally prepped for SCCA T1, I bought and had a set of T1 sway bars put on with everything else stock except for lowering 3/4" and a more aggressive alignment than you are looking at.

I did a DE at Portland with Kumho Ecsta MX in front and the stock F1SCs in the rear. I thought the car handled better than it did stock, with body roll noticibly reduced. I was keeping up with and passing guys on Hoosier tires, so the setup couldn't have been all bad. Wasn't passed all day.

My only complaint with the T1 bars on the street is that the metal to metal endlinks creak and groan. I've read that you can use other endlinks that don't have this problem.
:cheers:
The T1 setup was never intended for street use. Road race only. Most of my suspension was done by DRM/Thunder Racing and they recommended Bilstein custom-valve coilovers, urethane bushings, lowering, Z06 sway bars, and non-metal end links. The metal endlinks on the T1 will grind down and just get progressively looser and louder if the car is driven on the street...
 
#15 ·
BLEUBYU said:
DJ - a couple of questions/comments re your post:

1. Brakes: Have done the Goodridge SS lines but used ATE fluid. Your opinion of ATE? I am looking hard at the VBP Xtreme ThermoDuric 2 Piece front rotors. They claim that these rotors are 2.66 lbs lighter (each) than stock fronts saving a bit of unsprung weight, are slotted and are treated to deep -300 degree cryogenic cycling. Do you have any experience with/knowledge of these pieces?

2. Comment - I installed the LAPD tunnel stiffner, '04 shocks, and went to the following alignment: Front camber -1.2, caster 7.0, toe 0, rear camber -1.0, rear toe 1/32 toe in. Car seems to handle very noticeably better. Alignment was for street with some track time - do you think this alignment set-up is ok?

3. Your comment re the hydroformed aluminum frame seems to indicate that GM will substantially raise the price of Z06 entry to at least the high $60's? This seems especially true if they are planning on a run of 3,000 or so Z's. Also, I would think the aluminum frame rails will need to be substantially "beefier" than their steel counterparts since aluminum is not as strong as steel. Agree?

Thanks!

:cool:
Baer Racing has done extensive research into cryo rotors, cross-drilling, vane direction, hole size, etc. The cryo treatment is apparently a waste of money which is why they don't offer it. If it isn't proven via hard science, they don't bother. I've run Eradispeed 1+ rotors (14.85" front and 13.5" rear) hard for three hours at a time and not had a lick of problem. No fade. Castrol SRF, Goodrich SS Lines, SBS pads, Alcon 6 pots. Stops on a dime with a nickel and four pennies change. :)
 
#16 ·
BLEUBYU said:
DJ - a couple of questions/comments re your post:

1. Brakes: Have done the Goodridge SS lines but used ATE fluid. Your opinion of ATE? I am looking hard at the VBP Xtreme ThermoDuric 2 Piece front rotors. They claim that these rotors are 2.66 lbs lighter (each) than stock fronts saving a bit of unsprung weight, are slotted and are treated to deep -300 degree cryogenic cycling. Do you have any experience with/knowledge of these pieces?

2. Comment - I installed the LAPD tunnel stiffner, '04 shocks, and went to the following alignment: Front camber -1.2, caster 7.0, toe 0, rear camber -1.0, rear toe 1/32 toe in. Car seems to handle very noticeably better. Alignment was for street with some track time - do you think this alignment set-up is ok?

3. Your comment re the hydroformed aluminum frame seems to indicate that GM will substantially raise the price of Z06 entry to at least the high $60's? This seems especially true if they are planning on a run of 3,000 or so Z's. Also, I would think the aluminum frame rails will need to be substantially "beefier" than their steel counterparts since aluminum is not as strong as steel. Agree?

Thanks!

:cool:
Is this the current recs for street/track?
 
#18 ·
ATE is a good racing brake fluid an works well. AP 600 and Motul 600 are better. Motul 600 is cheaper. I use the AP600 as it is less compressable and has better modulation. It is also kinder to the seals and less hydroscopic than some. Howeveer it is not compatable with any other brake fluid.

I do not have experience with VB&P Cryo'd rotors directly but know others that use them. They are a good product.

I do not know how much actual testing Baer has done concerning Cryo'd rotors. I have seen data from others including electron microscopy. I also hav extensive experience with them on my own cars and other race teams that I have worked with an can catagorically say thet Cryo'd rotors will last 2-3 times longer than a non-cryo'd rotor of the same material.

Furthermore, I do not recommend the Eradispeeds for track use. Although they are a fine street rotor they will not hold up to heavy track use. Nor will any drilled rotor. Rotors are drilled primarily to reduce weight. Although cooling and outgasing are improved slightly. The problem with drilled rotors are that they develop stress and heat cracks more easily. I prefer a slotted rotor or one with "cast in" holes vs. post manufacture drilling.

The T1 set up was intended to up grade a regular C5 for the track. The Z06 is very trackable off the showroom floor. It can be improved upon however and the T1 bars will help, but the improvement is not as great as on a C5.

The so called T1 "metal to metal" end links are in fact hemi-jointed sperical bearings. They are far superior to the OEM end links. They need to be maintained with frequent lube and kept clean. If done so they will NOT wear out and degrade. However bear in mind that if you use them on the street on a daily driver they will get wet and dirty. You will have to clean and lube more frequently. An alternative is teflon lined sperical beaings which run cleaner and do not need lubed. They still have to be kept clean on a routine basis.

The 3000 Hydroformed Aluminum frames may be the initial run or they may be a limited run for the rumored "Blue" or they may be for the Cadillac program.
 
#19 ·
Thanks - as always, DJ. :thumb: Would have liked to go the ti rotor route, but they are just too expensive for me!
 
#22 ·
Turn the wheel to lock, wipe of the dirt, apply thin film of grease once a week. Prolem that most people run into is that they apply too much grease which acts as a magnet for the dirt & grime.

if you drive thru water or rain then you should lube afterards and more often..

As was the case with the T1 bars, the Hotchkis bars were engineered to improve a regular C5. They really do not offer much improvement over a Z06 bar...almost imperceptable.

What is needed is a bar half way inbetween the t1 and Z06.
 
#23 · (Edited)
Has anyone tried the Handling Plate in a drag racing venue?

I believe it will greatly improve the transfer of power to the rear wheels, due to less frame flex.

I edited info and started a new thread. Did want to seem like I was hijacking this one
 
#24 ·
I tend to disagree. The T1 bars are mega stiff. The Hotchkis bars are stiff, and the Z06 bars are a step below that. This is shown by the diameters and wall thicknesses.

But more importantly is the improvement in balance the Hotchkis bars make. After I installed them there wasn't even a hint of understeer remaining in the car. A huge improvement over stock.

Here are the numbers - notice how the front has a slight increase in torsional stiffness, while the rear is a big change in torsional stiffness, thus the improved balance in grip between the two ends of the car.

Base:
Front 23mm, 3.81mm wall thickness
Rear 19.1mm, 2mm wall thickness

Z51: (00 and up)
Front 28.6mm, 4.15mm wall thickness
Rear 23.6mm, 3mm wall thickness

Z06:
Front 30mm diameter, 4.5mm wall thickness
Rear 23.6mm diameter, 3.5mm wall thickness

Hotchkis:
Front = 31.75mm diameter, hollow, wall thickness = 4mm
Rear = 25.4mm diameter, hollow, wall thickness = 4mm

T1:
Front = 38.1mm/1.49" diameter, hollow, wall thickness = 6.35mm
Rear = 26.98mm/1.06" diameter, hollow, wall thickness = 6.35mm
 
#25 ·
Lambinator said:
I tend to disagree. The T1 bars are mega stiff. The Hotchkis bars are stiff, and the Z06 bars are a step below that. This is shown by the diameters and wall thicknesses.

But more importantly is the improvement in balance the Hotchkis bars make. After I installed them there wasn't even a hint of understeer remaining in the car. A huge improvement over stock.

Here are the numbers - notice how the front has a slight increase in torsional stiffness, while the rear is a big change in torsional stiffness, thus the improved balance in grip between the two ends of the car.

Base:
Front 23mm, 3.81mm wall thickness
Rear 19.1mm, 2mm wall thickness

Z51: (00 and up)
Front 28.6mm, 4.15mm wall thickness
Rear 23.6mm, 3mm wall thickness

Z06:
Front 30mm diameter, 4.5mm wall thickness
Rear 23.6mm diameter, 3.5mm wall thickness

Hotchkis:
Front = 31.75mm diameter, hollow, wall thickness = 4mm
Rear = 25.4mm diameter, hollow, wall thickness = 4mm

T1:
Front = 38.1mm/1.49" diameter, hollow, wall thickness = 6.35mm
Rear = 26.98mm/1.06" diameter, hollow, wall thickness = 6.35mm

I do not understand HOLLOW, I thought all the C5's had hollow sway bars?