KuzVette

This may have already been asked, but can someone net things out for me on what is the actually technical performance difference between a C7 with the Z51 option and a base Grand Sport?

I thought the only difference was cosmetics and maybe some suspension differences taken from a Z06.

ersatz928

Assuming you are comparing a Z51 with MRC, against a GS (MRC is standard) : GS has wider wheels, wider tires, and bigger brakes. The rest is just cosmetics. And it weighs more...50 or 60 pounds I think.

KuzVette

Thanks ersatz928. So GS shares the same wheels/tires as a Z06?

Also, is it fair to conclude that if the Z51 has the same options outside above, performance wide is the "Same"?

dashotgun

1 huge difference is you cannot get runflats all seasons in GS or Z-06 sizes yet. if that is important to you

X25

The suspension tuning is done per traction available from the tires. As such, the spring rates are different, and I'd imagine the MR shocks would have a bit different tune. If you plan to modify your suspension and use different tires anyway, then it's not too big of a deal. However, if you will keep it stock, wider rubber will provide more traction and have the appropriate suspension tune for it.

jcsperson

I had originally intended to get a Z51, but after seeing everything you get for only a $5,000 premium over the Z51 it was a no-brainer. It has larger diameter rotors front and rear, significantly wider wheels and tires, the wide body and aero bits like the splitter and side skirts, GS springs and sway bars tuned to the tires, and standard magnetic ride control, a $1795 option on the Z51. If you look at the difference in prices of used C6 Z51s and Grand Sports, you'll see the GSs hold their value better down the road.

KuzVette

Thanks jcsperson for you feedback. I agree that a GS is a good buy, I got a 2016 Z51 in December, 2015 and wanted to wait for the GS to be announced, but I wanted the NRB color and had to pull the trigger.

The real question I was soliciting feedback on was "Is there any real difference in performance?"... I hear people rave about the performance of their GS, but I believe that my Z51 is just as good but doesn't have and GM badging (e.g. Z51) like the GS.

ersatz928

I think a Z51 with MRC would give you similar track performance of a GS, and might actually have a very slight advantage due to its lighter curb weight, lower wheel/tire weight and lower drag. I am guessing that the larger GS wheels and tires weigh more than those of a Z51. The biggest advantage for GS performance is better braking ability and more fade resistance.

Here are links to the performance impact of heavier wheels/tires :
http://www.caranddriver.com/features...d-tires-tested
http://www.focusst.org/forum/attachm...wheel-test.pdf

Everybody is raving about the GS because that's the "new thing", but a head-to-head track comparision would show minimal differences.

jcsperson

Everyone is raving because of this video:


2:47.1 represents the 9th-fastest time ever in the Lightning Lap, faster than a 2012 ZR1 and almost seven full seconds faster than the Cayman GT4. It's only .1 second off the 2016 Porsche 911 GT3 RS.


2:50.7 – 2012 Corvette ZR1 (Michelin Pilot Sport Cup Tires)
2:51.8 – 2009 Corvette ZR1 (Michelin Pilot Sport PS2 Tires)
2:53.5 – 2011 Corvette Z06 (Z07)
2:53.8 – 2014 Corvette Stingray (Z51)
2:58.2 – 2007 Corvette Z06
2:58.5 – 2010 Corvette Grand Sport

X25

It's still the success of the platform, not just one model. C7 Z51 needs wider tires, and GS/Z06 provides them.

If you will never modify your car, and attend track days, then GS w/Z07 as referenced in that video is an excellent choice. Key note here is that regular GS will not be close in performance to Z07 model, even if you swap your tires with Cup 2s.

If you will modify your car (and attend track days), though, then you have different alternatives. C7 Z51 + coilovers + wheels will be just as good as Z07, if not possibly better. Considering GS w/Z07 also needs wheels (since at 19"/20", there are no good tire choices), it becomes a pretty good option.

As everybody says, it depends on what you want to do with your car, but key points here will be place of use (mostly track or mostly street), if you will modify it or keep it stock suspension/tire-wise, and initial cost vs. money/time cost of mods.

Keep in mind, magazines always test the cars bone-stock, and will review as such (a good example to this is brakes; iron brakes with race pads that sacrifice street use are usually just as good as CCBs, if not better, in terms of brake feedback, bite, etc.). The magazines' recommendations are usually spot-on if you will leave the cars stock. If not, you should consider your options to make the right choice.

ersatz928

Did the 2014 Z51 have MRC ???

X25

That Z51 grenaded its engine. They only made one hot lap per C&D.

Liter of cola

people rave about the performance of the gs because it handles like the z06 should of handled.


the grand sport murders the z51 on track.

rrsperry

As tested $92,060...

My 16 Z51 (bought Sept 15) out the door, ( LBR, with NPP, nav/ data , 2lt, MRC, 7 speed, black machined wheels) was $70,000.

Hardly a $5k difference.

Liter of cola

I paid $67k for my gs that had an msrp of $76k. I was OTD at $73k

Unforunatley i dont have the z07 package but oh well its overkill for the street anyways.

jcsperson

That GS must've been a Z07. Compare apples to apples. Mine is a 2LT non-Z07 with PDR, black wheels, red calipers and carbon flash mirrors and spoiler. Mag ride, a $1795 option in the Z51, is standard in the GS. MSRP on my car was $73,985. I was looking at a Z51 with similar options with mag ride and the MSRP was a tick over 69. It was a while back and I don't remember the exact number. I paid $64,182 plus tax and license. The Z51 was around 59K.

For $5K I got the wide body, aero pieces, wider tires & wheels, bigger brakes and GS suspension. This is mine at Kerbeck's on Saturday when I picked it up:



That sounds about right. Congrats.

Liter of cola

Thanks brother... you did get a better color than me. But black aint bad either.

l2vette

Can you please elaborate on that statement.

KuzVette

Thanks for the question l2vette.. I was thinking the same thing.. I understand the "Handling" may be a tad better, but how does that translate to raw power and performance?

What specifically does the GS have that the Z51 doesn't? I know they have bigger tires than Z51, but don't they share the same suspension if you equip the Z51 with all the other options?

Thanks,

jcsperson

They have the same horsepower, but wider tires let you put the power down better. The extra width is worth a couple of tenths 0-60.