So I am on the fence about doing Z51 or not. The feature I like most on Z51 is the eLSD. However, I don’t know what the non-Z51 diff will be. Does anyone have info on that? I have to assume it won’t be a 1 legger, so is it just a traditional mechanical limited slip? Or is the only real difference the gearing? Any help is appreciated. Thanks.

 

Yeah, it's a mechanical LSD as opposed to the eLSD in the Z51. Also it has a taller final drive gear.

 

Thanls for the info. I suspect the extra .1 sec 0-60 between the two has more to do with rear gear instead of mechanical vs electronic LSD. I don’t really plan to track at all, so will probably skip the Z51.

 

Does anyone know differential gear ratio between the two? Seems all tranny gears will be the same. I’ve been looking and all things point to diff gears of 5.12 for Z51. (Which seem high but are ok with huge overdrive gears) However I’ve seen differences on non-Z51, one post says 3.42 and another 4.89. Jumping from 3.42 to 5.12 seems like a big leap, and would likely have a more dramatic result in 0-60, plus I know Z51 top speed is lower, but I would think those gears might be more limiting as well. So seems likely really jump is from 4.89 to 5.12, but can anyone confirm?

 

The gearing in the z51 in 6th is good for ~204mph, with the overdrive 7th and 8th gears being mecanically capable of ~270mph and 325mph. The limiting factor of the Z51 top speed is entirely aero and power. Just like the current C7, the factory aero brings the top speeds way down in favor of downforce on the track.

Per this post, 4.89 is what I'm inclined to believe the base model has in there.
https://www.corvetteforum.com/forums...me-anyway.html

 

Seems right, thanks again!

 

its 4.89 versus 5.17 which is a noticeable difference in seat of the pants driving. The car will accelerate quicker even during partial throttle operations. But the complexity of the ELSD over the non ELSD rear is one reason alone to possibly stay away from the Z51, also if you never plan on tracking the car and if the harder accelerating gears do not matter to you, get the base car with the NPP exhaust option and a rear spoiler option if you like the rear spoiler look of the Z51. There are 5 overdrive gears in the transmission so you cruising RPM will be very acceptable with either rear gear considering 8th gear is a .329 OD gear ratio. Real world 0-60 times between a Z51 and a base car maybe .2 difference. That is something you can feel but how much does that matter to you only you can determine. If you really want the quickest combo 0-30, 0-60, 0-100 MPH than Z51 it is

 

I see a number of guys set on ordering a C8 with the Z51 options package having no intentions of tracking the car convincing themselves that their C8 will be noticeably "faster" and feel much more powerful in street use. It wasn't this way with the C7s and won't be with the C8s. Horsepower is identical and there is a mere 5% delta in dif. gear ratio. You will not "feel" 0.1 second 0-60. The minute difference in gearing may optimize the Stingrays torque exiting turns on road circuits and can possibly be appreciated to some degree at that point. Z51 is obviously quite profitable for GM as it is really nothing more than a substitution of parts. It is great marketing to create the mind set that this option transforms a Stingray into a significantly faster street performer and a must have for many who subscribe. It would have to if costs $5,000, right? This is all a carbon copy of 2013 with the C7.

 

As others have said the non Z51 has the same as the C7 base, a 1960's posi! Works OK but eLSD is better and more that just for starting! Had a C6 Z51, 2014 C7 Z51 and now a Grand Sport.

When my number comes up, I'll get a C8 Z51. Don't Track but do drive aggressively and prefer the stiffer suspension, Z51 shocks (I'll get the MRC but the Z51 standard shocks are larger than the base as they were in my 2014 Z51 without MRC.)

 

JerryU
you are more like me in this arena with the difference being this is my last vette due to my age.
I was going to make my upgraded 2015Z my last car but wanted to own a mid engine to complete my string of vetts.
I will do a Z51 with mag shocks and the lift kit.
Ive had the privilege of riding in and experiencing several C8s a special gift to me and a friend. If I were a younger man I would await my choice to own a C8 Z06 , but knowing my diminishing physical age slide I will do the Z51 for several reasons.
First: the price asking is a bargain for the additional engineering we will receive for the performance. Most of us won’t be able to tell the difference until we put the car in it’s purposed design status...the track. I will not limit myself just because I won’t track it but the next guy who buys probably will.
The only way I can get the magnetic shock upgrade is to have the optional Z51 package. I want the mag ride availability because I want the options that will come with this system which will me to program the ride comfort to a softer cruise from a more rigid ride that comes with out the mag upgrade. I drive long distances up and down the west coast each year thus putting extra miles in the cars I own.

You will I’ll love your new C8 no matter what package you buy. The performance will astonish you!
Good lick

 

Never know- may still get a GS after but will be 77 this week and have "hold-a-spot" money down on a C8, which will also be a Z51, MRC and a lift kit (high wing and ground effects as well.)

Paul Newman was my car hero winning an SCCA race at 81 but as I get older I look at Cris Karamesines! At 86 he drove his AA Fuel Dragster to 305 mph last year and qualified in some NHRA National events this year!

 

If the Z51 car with the tires and gear can be or will be .1 or .2 faster to 60 MPH it really is noticeable on the street where 0-60 or even -0-100 exist on a regular basis. Even a 20 - 60 or 20-70 street race that .1 is a significant difference and can be felt. The key thought here is acceleration from a dead stop or a very slow roll and running up to 70 mph, the 5% gear ratio difference is noticeable and of importance on the street.

 

Yeah, it will be noticeable to the guy who paid the $5,000 for it. LOL!

You can feel 0.1 second difference 0-60, sure you can. Get real.

 

For straight line drag racing especially from a dig, a mechanical limited slip rear is better than the ELSD. There already is program tune update for the ELSD to make it grab harder internally for the tire clean and heat process (burnout) to clamp the clutches tighter for equal spin on both tires meaning less slip. Less slip very important for 60 ft times .

 

First of all the car Z51 will probably be closer to a .2 diff to 60 versus the base car. Yes I can feel a .1 difference to 60 mph. Just like I can feel the difference in a car that comes out of the hole at a 2.0 60ft time versus a 1.9 60 ft time. Spend time at a drag strip testing your car and monitor all your short times, you see it in the clock and feel it in your butt. Then watch your ET , a tenth quicker in your 60 ft time is good for .2 in the 1/4 mile ET or two full car lengths generally speaking.

 

^^^
Just braze the spider gears if all you're doing in drag racing!

That is what we did "back-in-the day before posi!” Had a special 4:56 rear we'd swap in with locked spider gears when drag racing!

 

Look at all the other goodies that come on the Z51 package, the 5k is worth it. Also the track capabilities are much higher on a Z51 equipped car, all justifying the 5k price difference on top of a quicker 0-60 and 0-100 mph.

 

I hear ya on that, but now that makes street driving miserable. Pure drag car and nothing else, put a locker in there or a spool.

 

I agree.....and that's why I use Track mode at the strip because my base C7 gets a better 60 ft time
Launch control was useless for me on the strip. Actually, .1 is a big difference 0 to 60 mph. I could be totally wrong but this Z51 could be .2 quicker 1/4 mile. That's huge. But I just hope not.

 

Get the Z51 package any be happy with it. It will be faster to you because you are certain in your mind that you can "feel" 0.1 of a second difference 0-60. Really? You can't honestly believe that unless you are drunk.
The Z51's 0.18 numerical gearing difference will "feel" faster and stronger to you because you know it is there and think that for a $5,000 price delta it just has feel faster.
The reality here is that back to back to back to back 0-60 runs in either equipped car will yield a range of times which would confuse your highly trained and sensitive SOTP meter to an even greater degree as no two would be the same, some quite a bit different.
In the end it is flatly laughable for anyone to blindly fist pound the point that they can actually "feel" 0.1 of a second 0-60 MPH.