Hiya Jrho! Back at ya! I think that these numbers are BS. The posted chevy docs show lower ratios for the FD, but we don't have gear numbers. If memory serves 4.65 base and 4.80 for Z51. Perhaps the DCT is different, but with conventional gearboxes the lower the FD number the stronger the pinion is(bigger) and more compact it is (ring gear is smaller). It seems unlikely that 5.17 would make a ton of sense.

I think I would tweak your gearset a bit in that if the driveability could suffer a taller first, I would be good with it, but OK as is. 76-80 in 2nd is great, 105-106 in third, 130 4th and 150ish 5th is pretty much a must-have. The only other concession to reality I would make is probably a slightly taller 7th for smoothness and economy, but I could be argued around. Ah screw it, let's get this made up! :P

 

This solidifies my decision not to spend the $5K on the Z51. It has some nice track upgrades, but for the overwhelming amount of buyers (95%+), myself included, who will never track the car, I don't see that the Z51 is worth the negligible .01 quicker 0-60. You can get the NPP and Z51 ground effects for $1,700. Add in the savings of not having to buy a second set of wheels and tires for winter an it sweetens the deal. You loose Mag ride, but from what I hear the non-Z51 suspension shouldn't jar you too much anyway.

 

My question is: WHO needs a Z06?

 

I agree....the performance data doesn't appear to be final.

 

I have a bad feeling this data is legit, Tadge has stated the Z51 needs two shifts to reach 60.

The prescribed 7-8 shift has a similar % drop as 2-3 and 3-4 in the OE gearset - so not super close but probably not beyond the range of what the computers could make happen smoothly.

The C6 and C7 Z06s and all Vipers since '03 have 60+ mph 1st gears... my prescribed 1st (and 2nd) could maybe be shortened a little, but again, I can't imagine it's outside the range of what the clutches can handle smoothly, and is already about 20% shorter than those cars.

 

Who needs a Corvette?

 

Not really, the C8 will be much easier to pull a sub 3 sec 0-60 even a great 0-100 pull on the street compared to a A8 C7 Z06. Anyone would have a hard time on the street duplicating quick C7 Z06 times which were probably achieved on a prepped track allowing a decent hook and times that cannot be achieved on the street .The lesser horsepower C8 with 60% of its weight in the rear will hook better on the street.

 

These times will definitely be slower with two sets of golf clubs in the back.

 

It commonly stated that you should keep engine rpm between peak torque and peak HP. The reality is you want to have maximum area under the power curve between shifts, while still have a transmission that allows practical driving between minimum and maximum speed (0-193 mph). Oh and meeting mpg targets. On a street car, That usually means shifting slightly above peak power power and a little below peak torque depending on the flatness of the curves. I trust that GM has struck a good balance.

If you are a race team with infinite budget, you would change the gear sets to match the minimum and maximum speeds for your car on every track you go to.

 

For those using this data to decide on Z51 or not, it seems like as other posters have pointed out, the data is for Z51 getting to 60 mph and for getting to 100 kmph, NOT comparing base vs Z51 0 to 60. I still don't think we know 0 to 60 for the base?

 

Ran some thrust calculations - and the OE gearing makes sense for the traditional American truck-like torque curve. Perhaps in preview of the LT2 dyno sheet - look for a shape very much like the LT1, with a torque plateau from ~4250-5250, with torque dropping off 20% from peak by 6500.

It's too bad, with DCT tech finally available, there was opportunity to build a more top-end focused engine (even without raising redline), as there are plenty of gears to keep it in its happy place on track.

Will be interesting to see if they go more top-end focused with the Zxx versions, or if they keep this broad spacing and just throw more midrange at it via supercharger or undersized turbos.

 

Folks need to read between the lines of what Jeremy wrote here. Don't make any last-minute ordering decisions based on the charts that were photographed.

 

It shows top speed at 193 which leads me to believe it's the base car not the z51. To the 20 people in this thread who said that solidifies their choice not to get a z51. The performance data posted here is not Z51vs base but 0-60 MPH/ 0-100 KPH.

 

While that is commonly stated, it is not true, when it comes to maximum motive force to the driving wheels,.
It is one of many misconceptions and "old wives tales".

 

So it gets to 62mph faster than 60mph? How do you figure that?

 

Yep. Waiting on some official numbers and independent testing.

 

Seems like someone in management saw that they had the potential to get a sub 3 sec 0-60 time. They then decided that that single metric would drive more buzz and thus more sales than anything else and that became the driver. "So the computer models say that with Launch control we can make use of the short first AND it is good for DCT start from stop, but with lower power we need a short 2nd, but that doesn't give us 60mph, so I we need a short 3rd to get us there. But we need to be a good cruiser, so we'll make the top 3 gears tall. Track? use the 2 in the middle!" Simple!

The sad thing is that management was probably right. The vast majority of corvette owners don't care about any of this nonsense and sub-3 for less than $60k is a compelling headline. Oh well, the goodness of buying a car that hits such a wide demographic is that you get good value for money. The bad part is you don't get custom tailored solutions. This is why the GT3 is so special.

Chevy, if the rumor about the TT DOHC Z06 is correct, please make the grand-sport with the NA version of that engine with about 13:1 compression, 8500RPM redline, 77mph 2nd gear, with close ratios for 2nd-6th. 7-8 can be cruisers. Want to keep the Grandsport the way it is? Call mine the ZORA and put me #1 on the waiting list. I can dream.

 

I'm pretty happy with my C7 Z06. If it didn't have the larger brakes, or the magnetic continually adjusting shocks, I probably wouldn't notice much difference.
But the extra power is hugely noticeable, and a lot of fun.

 

I think it's just poorly written and not meant for the public eye, same reason MPH is captilized and kph is not.

 

The tailoring of a GT3 has more to do with PTS and other mostly non performance related options. You do have a choice between a manual and a PDK but the difference in performance between the touring, GT3 and GT3 RS will be similar to the hierarchy of base, Z51 and Z06. It's not like you can tailor the gearing, engine choice etc..