Dynamometer comparisson between Corvette C6 ZR1 and 2015 Corvette C7 Z06 discloses extent of failure of newest flagship

As already described here, the absolute numbers never tell the whole story, no matter how much the +General Motors marketing  and  +Tadge Juechter kept wishing this was the exact case.  Throw a few numbers like maximum horsepower, torque or 0-60 time and kool aid drinking Corvette enthusiasts and better yet, potential buyers will take the bait, loving every moment of their ignorance.

Of course when the numbers are not superior to the competition or predecessors, these numbers become MIA but this a complete different story.

By all accounts, the newest Corvette flagship, C7 Z06 is a failure and a sad testimony to the mentality of General Motors corporation as a lair of budget oriented supercars.  Furthermore, what happened to the C7 Z06 shows even better that the understanding of the subject and dedication to high performance are not required to run the Corvette engineering and development programs, unless someone considers turds like Cadillac XLR valid substitute for an actual high performance sports car capable of setting new performance bar.

Nevertheless, the current chief of the Corvette program, Tadge Juechter dedicated a serious chunk of his time to insinuate that the newest flagship is not only cheaper and superior to just its direct name sake, C6 Z06 but also far superior to ubiquous Corvette C6 ZR1.  By all accounts, this WAS a very ambitious contention that unfortunately failed on all accounts, without a chance to improve the latest flagship to the point where it actually live up to the marketing hype and bullshit disguised as Tadge Juechter's "engineering expertise".

Going back to the numbers and C7 Z06 being a car superior to the last ZR1, there is nothing more revealing the always popular and revered by the Corvette crowds dynamometer comparissons. 

On the surface, the newest Z06's LT4 powerplant should be a superior one to the LS9 engine.  Is this the case?  Unfortunately for Tadge, the exact opposite applies, painfully disclosing the extent of failure of the newest flagship.  Again, this is not about the absolute numbers but instead, about delivery and distribution of what these numbers represent, torque and horesepower specifically.

Right off the bat, when compared to the LS9, LT4 power and torque delivery indicate that the engine is literally choked up, literally running out of steam at higher RPMs, making the LT4 set up suitable for a low revving pick up truck with hauling duties and not a high performance sports car or perhaps, a muscle car, good for a  quarter mile run and nothing else- A ONE TRICK PONY. 



Past 5k, the LT4 torque drop off is quite dramatic, offering very little to support high RPM shifting and removing motivation to shift at higher RPMs and higher speeds, with a hope of meaningful acceleration (there is literally no torque available due to that drop while the excessive drag, heat soak and weight are there).  Of course, to make the matter even worse, numbnut Juechter decided to go with very tall 5th and 6th gears to assure there is no high speed acceleration.  Again, the torque drop is one of the worst around, at about 160 ft-lb BEFORE ACCOUNTING FOR HEAT SOAK.  The 5250 RPM point is the horsepower gain limit for the LT4, creating quite a foregiving plateou to cover up shifting mistakes but offering nothing in the extra performance potential.

How about LS9?  Certainly, and this must be pretty embarrassing for Juechter, the torque and power distribution for LS9 is superior to LT4, enocouraging higher gear change points and assuring good high speed acceleration and better potential for high top speed.  Of course, the aerodynamics of the car assure that this is the case, as well verified in real life.  Funny how that supposedly obsolete power plant, with no DI is like an Energizer bunny, showing no signs of running out of steam while the DI and VVT high compression technological marvel runs out of steam long before the purpose of the car would dictate.  To illustrate this point, the obsolete LS9 loses about 85 ft-lb between 5000 and 6500 RPM while the "superior" LT4 loses over 140.  Of course, these are dyno wars, with higher spinning smaller supercharger/heat pump and underdesigned engine and intercooler systems increasing this problem for LT4 substantially after a few minutes of spirited driving.

The torque and power curves of LS9 certainly do not resemble a pick up truck hauler and invite shifting right at the redline, rewarding the driver with extra performance gains where they should be in ultra high performance car.  By comparisson, the LT4 looks right down boring, guaranteeing shredded tires but failing where the extra torque would be needed to overcome the shitty aerodynamics of the newest flagship.

However, there is another aspect to this comparisson and of course this is where Juechter likes to remain very quiet:  PERFORMANCE UPGRADE POTENTIAL.  From these graphs, the obsolete LS9 comes out the real winner here, showing rather clearly that not much money can be spend to increase its performance, this part is not a big surprise of course, if someone understands the impacts of the approach numbnut Juechter and his team took.

The bottom line here is the LS9 is a considerably better design high performer out of the box, a real screamer, at least when compared to LT4 but then again, what is not?