OK, wanted to start a separate thread to post the progress and development of my "clubsport" themed track build. I've already added some of the parts for the build, and in the next couple weeks will be receiving some other really exciting additions to take this car to the next level.
Somehow, I have managed to already put 5000 miles on this car in about 8 months, most of which are driving to and from the track. It hasn't missed a beat, knock on wood. It's going to get a well deserved break over the winter, and get some shiny gold goodies soon too.

All these mods have added some meaningful performance for track use, while not compromising any of its daily usability. I would highly recommend any of them for anybody looking for a dual-purpose car.
Here's what's been done so far, along with some pics:

• Competition Motorsport harness bar (I like this one because it offers a flat black color, and no harness hoops (which I think just look ugly and aren't really necessary).
• Schroth GT3 bucket 4-pt harnesses - these have 2" lap belts as well as 2" shoulder belts, and can come with the endurance adjusters. They are the best 4pt belts on the market for use with any club/bucket style seat for the track. They work great with OE comp seats. My shop did a great job with the very OE style install.
• Paragon Jack pucks and front wheel rock guards
• Speedway Composites Rear Chassis brace - Chevy offers one that is functional too, so that tells me it's an area that can def be improved. This brace is lightweight carbon tubed, easy to install, and shown to increase rear chassis stiffness by 8-10%. That's almost 3 times stiffer than the OE chevy brace. Anything that will tighten up the rear end and allow the rear suspension to do its job better is a no brainer. Once installed it is very stout.
• Paragon cat-back exhaust - sounds amazing, exotic, and removes 30lbs from rear of the car. Makes a tiny bit more power, but that was never the goal, weight removal from the rear of the car is king. That said, I also have a Corsa Race cat-back that I plan to install and test as well. Interested to see if the Corsa is louder. Same weight for both.
• RSC 2" wing riser for OE Z07 wing - these are great. Perfect match of OE carbon weave and they raise the wing to a level which is should have come stock. Adds some more downforce by getting it up higher in cleaner air. Looks sooo much better. No downside. Bolts right up to factory wing and decklid.
• Z51 OE Rear Swaybar - as noted, dramatically increases performance of the car. Much better rear chassis control. Inspires confidence on track, reduces understeer. Virtually no downside to this mod, especially if you want to keep stock Mag-Ride dampers. Data proven performance increase on track.
• Girodisc Steel rotor conversion - I'm a steel rotor guy. Sure, they are alot heavier than CCB, but also will last a long long time, and replacement costs are cheap. Plus, alot less stress removing these giant wheels and not worrying about cracking a carbon disc in the process.
• Ferodo DS1.11 pads - very good on discs, excellent modulation so that you don't get into ABS too easily. It's a proven pad that works with anything from 300TW street tires to Pirelli slicks.
• Antigravity LW Battery - Saves 25lbs. Car is a porker, so any weight loss helps.
• Apex VS5RS wheels - 19x11 and 19x13.25

 

The next round of mods should raise the bar a bit more:

Ohlin TTX damper kit - these need no introduction. Pretty much the gold standard for racing and track-day damper performance. Same shock family as used on the C8 GT3R and countless other GT3 and GT4 race cars. I use TTX kits on a couple other GT Porsche cars I track, and they are outstanding. This kit uses the inline rear and piggy back front TTX dampers (same as all Porsche GT3 TTX kits). Very compact, easy to install. Ride is AMAZING on the street, even with stiff spring rates. MCS was my other choice, but I ultimately went with Ohlins because I didn't want to run remote mounts. MCS requires remote reservoirs in order to run 900+lb springs, because they use an orifice for oil flow and do not valve specific to rates for 2WNR. You must use their more expensive 2WR or 3WR kits to run stiffer springs and get a dyno curve with your shocks. PSI (Performance Shock) in Ca have been my go-to shock supplier and tuner for years, and the premiere shock servicer on the country. PSI can provide a 2-way, 3-way or 4-way TTX kit. Will come with a nice clevis mount, which utilizes stock upper mounts. This allows for better NVH isolation, and also cost effective replacement if ever needed. Here are a couple teaser pics from another install, but my kit will also be using helper/tender springs. Prob goint to first test with 900F/1000R. If you aren't familiar with Ohlins TTX dampers, I highly recommend you read up on them. I'll post up some picks of my actual kit once it arrives shortly.

AMT sphericals - Lower rear control arms - had AMT install some sphericals into the lower rear control arms. That location is by far the most critical on the car. With so much torque/load going through those wheels, and knowing how sensitive this car is to any changes in toe/caster/camber, it is critical to keep that location as locked down as possible. We have had better success with alignment control by increasing the eccentric torque values, but I think the alignment will hold even better with sphericals in those locations, as well as offer better feel and consistent performance. If things move, I've got a set of AMT lockers on hand as well!

 

Phase I looks like a great list to get ready for some serious tracking. I am planning something very similar but have a non-Z07 car. Subscribing.

 

Nice mods! What tires are you running on the 19" Apex wheels? I'm running 19" 295/325 Nankangs, but could use more rear grip. I wasn't aware the DS1.11 rear pads are available, the last I saw only the fronts were made? I used these on previous Porsche GT cars and really like them.

 

Rear pads will be available soon, so running fronts for now, and will swap rears as soon as they are available. Using some Girodisc branded pads rear now, and they are fine, but want to swap to DS1.11 rears when I can. Creature of habit when it comes to brakes!

Currently, my CCB discs are at Pro-Systems Brakes (Alcon brakes), as they are using them for the engineering of the C8 Z07 iron conversion kit. As soon as I have those discs, will post up the details and picas they make "Endurance" HD style rotors and disc replacements for IMSA, Nascar, and many other applications and all makes/models including GT3 cup cars etc etc. I have replaced AP discs on a couple other of my cars with Pro-System discs, and when compared directly to AP and Girodisc discs, it is clear they are beefier and engineered for more thermal stability, over prioritizing cooling, which can lead to excessive/early cracking of discs when they get hot and/or cool down too quickly. They last longer and have more thermal stability. They should soon have the full CCB Iron rotor disc replacement kit available. They will be an even more stout setup than the Girodisc kit. As soon as I get them, I will post up pics and info, and I'm sure they will have them listed on their website as well.

Lots of buns in the oven!

 

The wing risers are cool but $1000 is steep. It seems like there might be benefit from an even higher wing, like 4".

 

May be time to add a roll bar just for added safety vs harness bar is my thinking

 

Alot of them on the market are junk. I'd say the Studio RSR and Trackspec designs provide real rollover protection by anchoring it to real structural areas. Most everything else anchored to the floor are just glorified harness bars, because the floor isn't a structural area. The chassis design of the C8 makes it difficult to make a functional bar. I'm not ready to start chopping holes in my bulkhead, yet. LOL. In the meantime, not crashing is the best protection.

 

I want to keep the OEM look of the car. The OE wing is very functional as is, and provides significant downforce already. Since it's a Z07 package, I don't want to ruin the look of the car with some big clown wing on the back, or shift the aero balance rearward too much with no changes to the front. That just makes the car handle worse.

 

Cool write up and build so far! As these parts get tested and best combinations figured out I think the C8 Z06 is going to be a mainstay at track days for years to come.

I have a 1LT Non Z51 that I daily drive that I am modding towards auto-cross events. For me it is much cheaper, less wear on the car, lower limits if I go off its into cones not a wall, don't have to worry about overheating, and mostly experience.

So far for performance I am trying to eliminate low speed understeer with the factory FE1 aligment for daily driving reasons.

I am interested if you had run the Strut Brace by itself and if you could notice any real difference. I am thinking this is my next mod to get but have been on the fence of the true benefits.

Currently I have the below "mods"
- Z-51 Rear Sway Bar
- PowerStop Z26 Extreme Street Performance BASE C8 Corvette Brake Pads
- Motul High Temp Brake Fluid
- OEM Z-51 PS4S Summer Tires
- Halltech Hornet C8 Corvette Cold Air Intake

 

Well for daily driving, low speed understeer shouldn't even be a thing, to be honest. The rear Z51 bar should be doing plenty for that. Add more front camber, or reduce rear camber/toe if you want to free the car up more, but seems pretty pointless worrying about how the car handles for daily driving.
The rear strut brace, if anything will help rear suspension work better, which means it will effectively lower rear spring rate, adding more toward rear grip (understeer). So you would want to potentially change your alignment accordingly to account for any rear grip gain you net.
For the street you may feel the car react a bit more sharply, and the feel of the car being a bit more cohesive, but these types of things aren't an OMG type of mod. It's about an 8-10% stiffness increase, which is nothing to turn your nose up at. Every little bit of chassis stiffeness helps, especially on track.

 

So the rear arms on this car are cheap, like $120 each. Make sense to just buy a new set, and drop-ship them to AMT for install. Mark is great to work with.
The front arms are known to cause steering vibration with the new electric steering rack when sphericals are installed, so leaving those as is. The front arms already have a stiffer Z06 specific front bushing in one position (all other bushings are the exact same durometer a Z51 cars), so for now my focus is on the lower rear. This should help hold alignments better, and offer more consistent rear handling. The rear uppers don't really do much for controlling alignment or location, and for long-term road and track use, I want to use sphericals in only the critical locations. Looking forward to getting them on the car.

 

I auto cross the car every other month or so, so trying to get it set up for that, lot of tight low speed turns. I just don't want to negatively effective daily driving. Thanks for the suggestions.

 

Oh, misunderstood. I set up all my cars for full track alignment, and don't worry about street driving. It is far easier to wear tires out much faster on track or auto-x with a "half-way" alignment, trying to keep things street friendly, than it is to align the car for proper track use and drive that setup on the street. All your tire wear is from events, and even more so if you don't optimize the alignment for them. I had friends that go to the track casually going through tires all the time, until they finally listened to me, trying to keep a "street friendly" alignment. It's a double whammy when you try to do that. First, your car doesn't handle as well as it should at events. Second, you end up burning up expensive tires even faster.

Add front camber, lower rear camber, or lower rear toe. Any of those, by themselves, or in combination, will help free the car up, and reduce understeer.

 

Thanks again! I tried to have the dealership do it but they were not inclined to adjust the alignment other than dead FE1 factory. I have since found a corvette specialty shop and will ask them about this when it goes in for an oil change next month. I have done 1 full track day in my C8 at Sebring and while it was fun the cost and time dedication was much higher. Also clearly a non Z51 car is not the right choice for that either (brakes and cooling) so been happy with the autocross events I can find in South/Central FL.

Appreciated it and will be following this closely to see how your Z06 shapes up. Cool there a couple full track builds going now.

 

On the Ohlins TTX can you adjust ride height independently from preload?

 

No, these aren't like the lower tier Ohlins Road and Track line (which are still great monotube shocks, BTW). You use helper springs to adjust ride height and preload. Virtually the whole body of the shock is threaded to allow for a super wide adjustment rage. A typical problem with adjusting ride height independently from pre-load, is then droop travel is limited, which is always a problem on track, and why you don't see high end shocks doing that. They already have shortened bodies with tons of travel, so it gives you more flexibility in ride heights, spring rates and lengths, and adjustment. PSI alread spec'd the appropriate length body and stroke size, which Ohlins has many options to suit any application. Here are some just as an example for the rear shock.

• TTX36 ILX 2807: length 283mm - stroke 68mm
• TTX36 ILX 3410: length 343mm - stroke 98mm
• TTX36 ILX 3912: length 390mm - stroke 118mm
• TTX36 ILX 4515: length 450mm - stroke 148mm
• TTX36 ILX 4917: length 490mm - stroke 168mm

Here is pic of the TTX on one of my other cars. It uses the same inline TTX36 damper for the rear, which has an integrated reservoir. You can see how the helpers are used, just like MCS and every other typical high end shock package.

 

What tires and sizes are you using?

 

Can you tell me more about running the Stingray rear bar on a Z or link me to some thread/info about it? I get the premise, just interested in what data is out there on it. Thanks man!

 

I believe I was the first to ponder this mod and test it, and gained 1 second/lap on a short 1:10 lap at my local club. Tons of laps there in the Z and other cars. No other mod was done, same tires, same weather conditions. The car is just so much better, as it controls the rear in transitions, due to its low spring rate. Other forum members have also now tried it (and sent me PMs) and confirmed the car is better on track, more confidence inspiring, and ultimately faster because of it. The bar is super cheap ($120) and very very easy to install, so it's a no-brainer to try for anybody who goes to the track. If you only street drive, then there is no point.

I have 6 or 7 other track cars, and a race car, all use Ohlins TTX or Bilstein Clubsport 2-way adjustable shocks that I set up (and have Performance Shock valve to my specific rates), so I have pretty good experience with setting up suspension for the track. After you drive enough cars on track, you just learn to "know" what a car needs from experience. Some is also personal preference. I prefer a free/neutral setup, most people do. For the majority of owners, adding this rear swaybar would be all they need to make this car perfectly acceptable for them at the track. For me, while the balance is better, it still has more body roll and is slower in transitions than I would like, and the rear "follows" the front, in that it feels like you are driving 2 cars on track, the front and the rear feel separate, disconnected. I've driven multiple Z51 cars with MCS shocks and they are a totally different experience because they have much more rear spring rate, and they are the same exact chassis. I'm not trying to talk everybody into a coilover setup, but I would say anybody that wants to continue using the Magride shocks for track use, should try the rear bar.