Project Z
The Return of Godzilla 
A continuing saga of the "Regular Guy's" super car

About two years ago we decided to do an article on a regular guy's C6.  We had originally decided to use a base C6 for our project car. The C6 has had an eight year run.  An enormous performance oriented knowledge base exists for this rendition of America's only sports car.
Our C6 Perfromance Manual is a great source of info for anyone contemplating some performance upgrades.With a few conservative mods a stock LS2 or LS3 can be transformed into a "kick ass" street machine.  

A decision was made to divert from our usual conservative path and go for broke. We threw caution to the wind and decided that the latest rendition of the Z car would make a very interesting platform for our next real world project car. Our first task centered around actually finding an affordable low mileage bone stock sixth generation ZO6. We spent about two months researching using on line sources such as Ebay, Corvette Trader, Vehix and After some very disappointing leads we stumbled on what we think was the perfect ZO6.

Our search led us to Maroone Chevrolet located in Pembroke Pine's Florida. Located just outside of Miami the dealership was within striking distance of our search perimeter. South Florida is an excellent place to look for used sports exotics. The bad economy has placed a very large number of these toys of the former rich and famous on the block. The toys are always the first things to go when times get tough.

The car in question was a victory red 2009 ZO6 with 5,800 miles on the odo. The car was loaded with a 2LZ package that included navigation and the optional chrome spider wheels.

The Z was in pristine condition and was certified by Chevy. The certification put an additional year onto the remainder of the factory bumper to bumper warranty.

The sales staff at Maroone Chevrolet was top notch.
We were very satisfied with the purchase as the car was essentially brand new. With under 6k miles the car was barely broken in. There was no pressure and they were very flexible in the negotiating process. To make a long story short we purchased the car for the price of a base C6.  If you can deal with being the second owner of a vehicle that is essentially brand new a slightly used ZO6 may be the ticket.  The afford ability factor is why we are calling our Z a "regular guy's" super car.  

The Beast
I still remember my first encounter with the Z.  We slipped into the cockpit, the doors shut with authority and the self adjusting windows sealed our fate. With the clutch peddle depressed and one push of a button the beast came to life. The dash lit up, the heads up display came on, the engine growled and we were off.

The ZO6 has more in common with a jet fighter than a car. Everything about this vehicle screams raw performance. Make no mistake about it, the ZO6 is an all out race car that happens to live on the streets. Bone stock testing puts the Z’s top speed at the 200mph mark.
Depending on your driving skills a quarter mile romp can be accomplished in the low eleven second range .

The ride is very firm but not jarring. Gear changes are accomplished with all the finesse of a hydrogen bomb. This car is not for the faint of heart. One word of caution do not even think about turning off the traction control on this car. There is so much raw horsepower on tap you will smoke the tires in each up shift. To say the least the power generated by an LS7 is very addicting.  

A recent test by Edmunds pitted a new Viper against a new ZO6. The Z blew the Viper away in every category. The Chevy broke all previous records by boiling the tires for 323 feet with a non traction assisted off the line banzai launch.

If you are looking for a silky smooth driving experience you had better stick with one of those foreign exotics that are mainly targeted for rich college girls. We hate to be chauvinistic but like it or not this is definitely a mans cars. The question that most new ZO6 owners may ask themselves is first, how does one possibly go about improving on such a great piece of engineering. Second, why would you need more than 505 horse power in a 3100 pound car? The answer is; hot rodder's never leave well enough alone.

The Real World

We have always tried to represent the needs of the average Corvette guy. We try to gear our projects towards what the average guy is actually capable of doing in terms of performance, body and interior modifications.
Each month the Corvette publications invariably feature a wildly modified late model Corvette on the cover page. The featured story follows a standard format. The format usually starts with an enthusiast with an excess of cash and time to burn. The Corvette starts out as a stocker and evolves into either a super or turbo charged 1000 plus horse racer.

Hyper Vettes are interesting to read about but are impractical to replicate
These projects usually involve top engine builders and tuners trying various combinations of after market parts. After these cars self destruct a number of times the tuners will come up with the perfect combination. The end result of the perfect combination is a really cool hyper Vette that is not really suitable for street usage.

We will be evaluating modifications that will not void the factory warranty. That task in itself has become a very tall order in this post carburated digital age. The tenents of hot rod basics; intake, exhaust and ignition modifications must be approached with the new digital age as a backdrop.

One of the first places that most people look for extra horses is in the intake system. There are some very well engineered after market intake systems that may give us what we are looking for.  But all is not well these days in after market land.

 Up until recently cold air intake systems (CAI's), did not really fall into the warranty voiding category. We have had several meetings with both GM and the after market manufacturers on the warranty subject. It is a very sensitive issue to say the least.

As per our recent conversations with the GM warranty guru's we are having problems with endorsing the installation of some of the more popular after market CAI units that are available.  Our stance on this issue will not win us any awards with the after market industry.  In fact our reporting of the truth has cost us a lot of advertising revenue, but that's the way it is. We don't work for the after market industry we work for the Corvette community.

GM claims that the oil from the CAI contaminates 
the MAF sensor. GM also claims that after market CAI's cause engine code anomalies due to excessively lean A/F ratios generated by an increase in air flow. The drive train warranty voiding issue presents itself when the consumer re calibrates the on board programming to compensate for the lean out condition.

We have spoken to some of the major after market manufacturers and they are behind a rock and a hard place over this.  We recently spoke with one of the most widely respected manufacturers of after market CAI's, for the time being we will not mention their name. This company has been trying to get GM to accept their CAI  products for years without much success. The oil contamination problem is a major stumbling block in the negotiations.

One extra word of caution if you plan on replacing your stock system with an aftermarket CAI.  Some after market units do a remarkable job by reducing the restriction of air flow to the throttle body.  The problem arises when that extra air flow increases turblance to a point that the stock MAF cannot compensate for.  Engine codes and surging at various speeds are the result of a poor air flow to MAF mismatch.  
The factory designed its air intake system to function in what they term as a "dead air zone".  They purposely avoided designing an outside air inlet that would affect the smooth air flow that the systems MAF sensor requires.  

Problems arise when old time hot rodders who are schooled in the art of outside air plumbing apply their experience on a system designed by rocket scientists and computer geeks. Traditional hot rodding theory states that introducing s free flowing stream of cold air into the plenum of an intake system will result in a denser air fuel mixture.  Colder air is denser air, allowing for more O2 molecules to ignite in the combustion process, thus more horse power.  This theory works great in pre rocket science hot rods.  With changing times comes new science.  The electronic wizardry inherent in the latest series of GM's LS motors has created that new science.

Cutting open the radiator shroud or installing air ducts in front of the air intake is a sure fire way to upset the dead air zone that the LS intake system was designed for.  The results are part throttle surging and the display of the P0171-0174 engine code.  The code is the result of the O2 sensor picking up an excessively lean signal from one of the cylinder banks. The factory service manual lists the following causes for this code.
  • The MAF (Mass Air Flow) Sensor is dirty or faulty. Note: The use of "oiled" air filters may cause the MAF to become dirty if the filter is over-oiled. There is also an issue with some vehicles where the MAF sensors leak the silicone potting material used to protect the circuitry.
  • There could be a vacuum leak downstream of the MAF sensor.
Unless you are prepared to give your car a custom re-tune, do not mess with the factory setup by introducing outside air into the dead air zone that sourounds the air filter element.

 very attractive option is the LS7 air filter element offered by Attack Blue located in Long Island, NY.   The Attack Blue air filter has a patent pending low restriction open mouth design that allows for huge amounts of air flow. The filter screens out dust particles down to 5 microns and has an air tight seal to prevent unfiltered air from entering the system. The manufacturer claims that the increased flow will not cause surging or mysterious engine codes.  

attack blue filter
The Attack Blue drop in air filter for the LS7

The filter was chosen by Magnason for their supercharger systems.  Recent dyno tests on a custom tuned LS7 showed an increase of almost sixteen horse power over the stock element, you can expect at least eight to ten extra horses without a tune.

The Attack Blue uses a multi layered oiled fabric in its filter medium.  It can be washed, re-oiled and reinstalled with a minimum of fuss. The manufacturer will swear on a stack of Bibles that the filter will not void your warranty. For those of you that have any doubts all you have to do is hang onto your stock filter and re-install it prior to dealer servicing.  As we stated previously do not attempt to duct fresh air into this filter. A custom tune will be required or the engine may behave erratically.

Our advise is if you want to do something to enhance the breathing of your ZO6 or for that matter an LS3 and do not want to incur the wrath of the GM bean counters try the stock filter element from the LS9 supercharged engine.

 According to some recent testing the LS9 filter
, GM part no. 25940997, will yield about eight additional horses, without the benifit of a tune, to an otherwise stock LS7. That's not too shabby considering that the after market CAI's only claim a ten to fifteen hp increase.

The only real problem with the GM filter is that it tends to clog over a relatively short period of time.  A significant loss of air flow can be realized after a short run through a very dusty environment.  The only recourse is to buy a new filter, at over $100 dollars retail an LS9 air filter replacement scenario can hurt a little. The LS9 filter is a direct fit for the LS7 air inlet housing, as we said it costs about  $100 bucks and your GM dealer will not have a problem with it.

ls9 air filter

A Great Bang for the Buck Intake Mod

Remember that more air does not always translate into more power, on the other hand a smooth air flow that travels faster to its target will always increase throttle response and usable horse power.  With this in mind we replaced the ratty looking stock bellows air coupler with a slick looking red silicone air coupler.  Testing of this simple product has resulted in power increases of 8 to 10 horses. There is no surging problem with this installation as the unit is located behind the MAF sensor. At a cost of under $60 this may be the greatest bang for the buck gizmo on the market.

ls7 air coupler

A simple yet Effective Exhaust Mod

The ZO6 is blessed with a very well engineered exhaust system. That engineering expresses itself with a pair of hydroformed exhaust headers with very uniquly designed quad flow collector flanges.
 The engineering employed in these GM hand made headers enables them to pass almost as much gas as most of the aftermarket units. Combined with factory 3" inch exhaust pipes its a hard system to beat. 

Option NPP, bi-modal exhaust, is standard equipment on the Z. The bi-modal exhaust is designed to allow for quiet operation during normal driving and provides for an aggressive exhaust note at 3500 rpm and above.  In the open mode the engine will produce about 10 extra horses.

There is an extremely easy to install gizmo that allows the driver to remotely control the exhaust note. The product is marketed under the name of "Mild 2 Wild".

Installation involves replacing a 10A fuse behind the passenger side kick panel and attaching a single ground wire. It really does not get any easier than this. The result is an exhaust system that will please both your wife and your gear head friends.  

One note of concern we recently had to replace the electric solenoid valve that controls the vacuum to the NPP muffler flaps. We have spoken to other people using the M2W controller and surprisingly the solenoid failure is a common occurance. At this time we don't know if the M2W bypass has anything to do with it, but we will keep you posted.

When in doubt as where to start you can't go wrong by adding some personal touches to your Z's interior. Some very simple yet effective ways to jazz up a dull GM interior include:

Resto Mod style center arm rest pad available through Mid America Motorworks. This required the removal of the arm rest lid from the console.

Air bag letter inserts, these letters were domed high gloss acrylic. The letters stick to the dash indents via 3M peel away backing. After prepping the installation site as per the vendor’s instructions we were unable to get the letters to properly stick to the dash.  We had to use some GE clear silicone glue to finish the job.  A better idea would have been to simply hand paint the letter indents. We previously did this on a C5 using a small bottle of Dupli Color paint that had a roller tip applicator.  The results were in our opinion superior to the vinyl inserts.  
(FYI as a long term follow up, the lettering is constatnly falling off or in need of adjustment, these things are a major pain in the ass.)

Color coded logo floor mats by Loyd, available from Mid America, go a long way towards perking up the Z's interior.

c6 door insertc6 door insert red

Colored door handle covers and arm rests are part of the package

zo6 stainless    

Stainless Steel and aluminum door, window and misc. switch covers from ACC match the factory alumimum trim pieces

The boring stock Vette steering wheel benefited by the installation of a two tone leather covering by Wheel Skins.  This installation required advanced sewing skills that no one in our shop had. My wife came to the rescue and the skin was perfectly installed in less than thirty minutes.

The stock steering wheel was still n need of something to give it a more updated appearance.   We contacted TKO performance, located in Bayshore NY for some help.
The companies owner, Ed Gentillie, fixed us up with a set of custom fabricated steering wheel steering wheel spoke covers that dramatically changed the appearance of the stock steering wheel.

corvette steering wheel spoke covers
The spoke covers are custom fabricated with an identical match to the color and fiber pattern of the stock C6 console.

c6 corvette carbon fiber steering whell spokes
TKO Performance carbon steering wheel spoke covers

The covers have custom rolled edges and fit seamlessly over the ugly stock silver spokes.  To say the least the new look is light years ahead of the factory set up.

A 427 hood insignia from GM lets the world know what's under the hood

C6 carbon fiber a pillar

Covering the stock A pillars with two neat looking carbon fiber replacements give a subtle exotic look to our Z.
A set of very cool looking real carbon fiber rear view mirror covers with matching carbon bases was also installed.  Installation is super easy, the covers snap on and are secured with 3M tape.  The fit and finish of these covers are outstanding.


Exterior carbon when used in moderation gives the Z an exotic "Euro" look


A set of American Car Crafts new "Black Stealth" front and rear grills help set off the look

carbon spoiler

We fitted a retro looking billet grill from American Car Craft to the front end.  Installation was super simple via the use of four zip ties that attached to the existing grill.  A set of Stainless driving light covers from ACC round off the retro look.

A blacked out set of AAC fog light covers blacked out side marker covers and a carbon Fiber front splitter from RPI finished off the front end.

The Engine Bay Factor

As you may have noticed hot rodding is in the midst of a dramatic evolutionary phase. Modern day gear heads have become infatuated with the "show" aspect of their cars. For the most part the factory has taken care of the "go" aspect as can be seen in our very stock Z car.  Winning a trophy at a local car show is replacing the desire to win a bracket race at the local drag strip.

The new need for engine "bling" is a topic for discussion can be further reviewed in our article on the subject Engine Bay Extravaganza. Our good friends at American Car Craft came to the rescue by supplying us with various shiny engine goodies to try on.

Some of the pieces that we are trying on for size include:

ACC stainless perforated alternator cover

fuse box cover

ACC plenum cover

ACC master cylinder cover

power steering cover with Specter chrome braided hose coverings.

ACC Stainless Fuel Rail Covers

ACC Surge Tank Cover with Custom Billet Caps

Stainless Air Intake and Radiator Covers by ACC with Domed Logo Insert

A very neat looking Stainless piece from ACC was used to cover the ugly dry sump cannister

We are also in the process of covering all of the remaining plastic engine bay parts with 3M gloss carbon fiber material.  3M carbon is a low cost alternative to real carbon fiber. It is super easy to install and the results look great. (We will be doing an article on this stuff in a future edition.)


A nice touch are the chrome hood latches, liner buttons and struts

  corvette zo6 chrome

The Work in Progress

Avariation on the all stainless steel theme presented itself to us after speaking with the legendary Steve Ray at Airbrush Incorporated.  Steve is one of the most sought after automotive air brush artists in the country.  After speaking to him about our project car he graciously offered to custom paint a set of fuel rail covers for our LS7.  

After installing them all we can say is "wow" the hybrid stainless/paint look is outstanding.  This is like having your cake and eating it too, we now have the option of using an all stainless theme by ACC or mixing it up a bit with Steve Rays art work.

We really wanted this project to be a little over the top so we decided that some lighting effects were needed.  Blue LED's were inserted strategically around the air brushed  "Jake" and cross flag mural on the stock hood liner.

corvette led lighting

We also placed some blue LED's under most of the perforated stainless steel engine covers. The effect even during the day are dramatic. In an effort to defer any further power drains the LED's are not on the Vettes stock power grid.  They are powered by a small rechargeable 12v battery that is mounted inconspicuously on the front fender well.
corvette led lighting

I guess we are doing something right as our car has won top honors at most of the shows that we have entered it in.

Let the Games Begin 


As mentioned earlier the ZO6 has an inexhaustible amount of power. The problem that immediately presents itself is getting that power to the ground.  The first hurdle that a newbie Z owner will face is mastering the art of manual shifting.  As in all skills practice makes perfect.  The Z’s short throw shifter will require some getting used to.  

 A banzai first to second shift is explosive.  The revs rise so quickly that there is virtually no time to second guess your decision. You will be at sixty mph in about 3.4 seconds, in first gear. A steady hand and titanium plated steel balls are needed to control a first to second up shift.  There will be a substantial amount of wheel spin on your first up shift.  You can minimize the smoking tires by gradually getting into the throttle on the first two shifts.  This takes some practice and discipline as ones first instinct is to just mash the accelerator pedal and hold on.  A high horsepower to weight ratio car like the Z requires a certain amount of finesse in order to get it motivated.

Don’t always count on the traction assist to bail you out. The enormous power of the Z will easily overcome the factories attempt to reign in the horses. If the wheels of your Z are not pointed perfectly straight you may find yourself going backwards at seventy mph. 

Before you start tinkering with power upgrades learn how to drive the car. You need to develop a consistent shifting technique. Pull straight back on down shifts and push straight up with the palm of your hand on up shifts.  Try not to rest your heel on the carpet while depressing the clutch.  

The short throw shifter makes for a sometimes troublesome second to third up shift during hard acceleration.  If you are not carefully it is very easy to go from second back to first gear.  The scream from your engine as you approach the rev limit of 7500rpm will surely wake you up.  To avoid this frightening situation always push the shifter towards the radio during a second to third up shift.
The second hurdle will present itself in the form of traction or more accurately a loss of traction.  The stock Goodyear F1 super car run flats are simply not up to the job of controlling the power of the Z.  The GY’s will break loose without warning. 

In our opinion the most effective way to increase usable power on the ZO6 is to replace the stock rubber. 

The problem for the regular guy is the current price of rubber.  The going price for a new 325 30R x19 run flat will range from $400 to about $500. This price does not include mounting, balancing and disposal charges.  

We took a look at some of the available tire options that are available for the Z. Chevy finally realized that the current Goodyear run flats are simply not suitable for the Z. The 2011 ZO6 will is shod with a new design from Goodyear.  The new Goodyear G:2 super car tires have proven to be an improvement over the old style F1’s.  

A great alternative that we can endorse are the Michelin PS2 run flats.  These are great tires that deliver a substantial improvement in both ride quality and traction as compared to the current generation Goodyear’s.  The only problem with an after the fact installation of the Michelin is the price. They run about $500 each, ouch.  

A sane tire alternative in terms of maximum bang for the buck is the Bridgestone Potenza 05A pole position run flats.  We were given a set of 05A’s to test, and test we did.  The Bridgestone’s totally transformed the basic character of our Z.  The ride is great, and power transfer to the pavement is now controllable.  The Bridgestone’s retail for about $400 each, not cheap but not out of reach. 

The addition of new rubber was like adding another 100 horsepower to our Z. The uncontrollable wheel spin that was an inherent part of the Goodyear’s was gone.  The Z’s 0 to 60 mph time dropped by almost half a second.  The dreaded first to second up shift was accomplished with a minimum of wheel spin.  

The addition of rear and front Bridgestone rubber has totally transformed the ride and handling of the Z.  GM should really be ashamed by the fact that they are still equipping high performance cars with less than acceptable rubber.

There is a definite point of diminishing returns when it comes to power upgrades in the Z06 Corvette. That point is in direct proportion to available traction.  When power levels in a 3100 pound car approach the 500 horsepower mark traction tends to get a little dicey.  

Adding a substantial amount of power beyond the 500 hp mark will not always yield the expected results. This situation can be observed when comparing the zero to sixty mph capabilities of a ZO6 and a ZR1. The ZR1 has a 133 hp advantage over the ZO6. GM claims that the ZR1 is about two tenths of a second faster than the ZO6 from 0 to 60.  This claim is pure GM marketing hype, the reality is that the lower powered ZO6 has more off the line traction and will easily keep up with its exotic cousin in a zero to sixty sprint.  

The point of diminishing returns was realized by a friend of ours who upped the power levels in his 2006 ZO6 to somewhere in the mid 700 hp range.  The car sounds awesome and engine bay is a show stopper.  The problem is that the car has no chance of hooking up on street rubber. The hyper Vette driver often finds himself out gunned in standing start drag races with stock ZO6's.  The tires on a stock Z will always hook up sooner and leave the hyper Vette spinning its wheels.  Depending on his driving skills the driver of the 700 hp Vette may or may not catch the stocker.  Our friend has to run slicks on the street, not a good idea, to avoid embarrassing situations.

That being said we still want more horses for our Z.  We are still trying to decide on whether to go with a normally aspirated LS7 (heads,intake,cam,exhaust and tune) or a blown version via the use of one of the bolt on Roots style superchargers that are all the rage these days. We are leaning towards the blower as we can get an after market drive train warranty from most of the manufacturers. 

The Vette Nuts