Ray G

Reading another thread someone mentioned this message from Chevrolet
"CAUTION! Per the Owners Manual, section 9-10, the center wickerbill needs to be in a lowered position to reduce the danger of loss of tire traction and to avoid reduced rearward visibility issues. The Manual also notes that the completed Stage 3 aero parts (including also the extra large front spoiler end caps/end plates) are for high speed track only."

Is this correct? I would think having the wickerbill all the way up would increase downforce therefore giving you more traction? Thank you for any explanations!

davepl

Sounds like an urban legend. I searched both the 2015 and 2016 manuals and this does not appear.

Section 9-10 just says the track settings include the wicker bill at full height. No warnings about it of any kind.

The letters "wicker" appear in the manual twice, and neither is a reference to what you're quoted there, so maybe someone just made it up... or I'm terrible at searching, one of the two.

BEZ06

with Dave!!

My 2016 Owner's Manual says:


Yeah, it says Stage 3 is "for track use only", but MANY of us drive on the street with the full Stage 3 aero installed with no problems.

And I've seen lots of different configurations at the track. A Stage 2 car comes with the small front splitter end plates, and the big Stage 2/3 rear spoiler extensions - with NO center clear wicker bill.

I have a Z07 with Stage 3 aero, but for high speed stuff (like Daytona, or a 1/2 mile event I went to recently), I reduce drag for higher speed. For those events I run what I call Stage 1-1/2 aero, which is the small front splitter endplates and Stage 1 rear spoiler wings:




As you can see in the video below, my Stage 1-1/2 aero doesn't cause any problems!!!



I think you can run whatever combo of aero you want, but the car has been tested by Chevy to perform best with the Stage 1, 2, or 3 aero parts used together with all the parts for that stage.

The adjustable center clear wicker bill is obviously designed for the owner to move it up/down for whatever level of downforce and rear vision they want!

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See06

LOL, I'm Dreaming of ....VRROOOMMM

Awesome video! Makes me want to get to the track right now !

rwheelz

Fantastic! Have you run the car into 6th and will it keep climbing? Is your top speed any different with full Stage 3 aero at Daytona?

CitationZ06@yahoo

Everything in life is a give and take. Just sitting still if you add 3500 lbs of force to the rear spoiler you will pop a wheely (and crush the trunk). If you add 300 pounds to the rear at 100 mph you lift 100 pounds off the front. It is a simple lever . So gm added front down force parts to keep balance.

Ray G

Thank you for your responses gentlemen.

BEZ06

I ran Daytona twice last year in the C7 Z06 - both times with the Stage 1-1/2 configuration.

I'll be running it again in April. This time I'll try to do some back-to-back comparisons. It may be one day I'll run Stage 1-1/2, and the next day I'll run full Stage 3 - it takes a while to get the Stage 3 front splitter end plates on.

You can see in that video that I was just short of redline in 5th and right into the area where I lift and start to slow down for T1 into the infield. I go to the Rolex 24 race every year, and I was again amazed this year at how far those guys go into that brake zone before I see brake lights!!! I'd need to go into 6th to keep going down as far as they do!!

I'm not gonna go that deep! But I'll short shift into 6th coming down the front straight of the tri-oval just to see how well 6th pulls.

I know my C6 Z06 with a 7000 redline would do right about 160 in 4th, but I usually short shifted into 5th about 6-6100 rpm and it would pull hard to 175 across the S/F line. I tried 6th occasionally and it kinda fell on it's face! You can see in the video below in the C6 Z06 that it's pulls real nicely in 5th. I probably could have gone a lot faster going to redline in 4th, but I was pulling about as hard as I cared to up on the banking in NASCAR T4.



My 2009 ZR1 (first year for the C6 ZR1) had a slightly higher ratio in 5th compared to the C6 Z06 (but more power), and the same 3.42 rear end (as does the C7 Z06). Unfortunately I don't have any video of it, but it did 185 across the S/F line and was right about its 6500 rpm redline in 5th when doing that speed. It should be almost identical to that video of the C7 Z06. The ZR1 did 185 very easily, and the C7 Z06 was really working to get to 182 - even with my Stage 1-1/2 aero. I think the C6 was a little more slippery.

The C7 Z06 has identical 5th and 6th gear ratios as the early ZR1 (then of course a much higher 7th), with slightly more power. I think the pull will drop off significantly with a shift into 6th, but it should still accelerate - I'll give it try in April, and if I can remember I'll give 6th a try with/without Stage 3 drag.

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Mad Dog 24

^ BEZ06, Thanks for your post and the comparisons to the other Vettes. It leads me to believe the C7 body design aside from spoilers has considerable more down force than the C6. Do you concur?

Next season I will try lowering the center wicker bill on ours to see if there is a noticeable difference. I've talked to others with ZR1s and C6Zs that run my track and they all complained about the top speed of their new C7s with "more advertised power".

cvp33

I left my rear aero on stage 3 and removed all of my front aero. The wheelies are a little disconcerting but absolutely controllable. I should add that I do have the DSC sport controller.

BEZ06

[QUOTE=Mad Dog 24;1594189305...It leads me to believe the C7 body design aside from spoilers has considerable more down force than the C6. Do you concur?...[/QUOTE]

Yeah - fer shure!! In my Stage 1-1/2 config the only thing that adds more drag than Stage 1 is the small Stage 2 front splitter end plates, and even in almost Stage 1 config it's noticeably slower than my ZR1 was.

So....I guess just the basic C7 body has more downforce/drag than the C6 does.

The ZR1 with 638 hp was touted in Chevy ads to have a top speed of 204+ mph, and the C6 Z06 was 198. I think the C7 Z06 top speed hasn't been published by Chevy because it's quite a bit less than the C6 ZR1 or Z06 - the C7 Z06 in Stage 1 aero probably tops out around 190, and Stage 2 and 3 less than that.

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spearfish25

Not so sure this reasoning is accurate. First, one can compress the rear shocks without 'lifting' the front. It's not a simple lever. Second, the force imparted by the air on the rear wicker isn't simply at the wicker. GM described the aerodynamics of the wicker 'bunching' air over the entire back hatch. Thus the downforce is distributed over the rear hatch portion of the car.

phantasms

I run large stage 3 in front and took wicker off the rear. I'm still alive.

CitationZ06

Quote

"Not so sure this reasoning is accurate. First, one can compress the rear shocks without 'lifting' the front. It's not a simple lever. Second, the force imparted by the air on the rear wicker isn't simply at the wicker. GM described the aerodynamics of the wicker 'bunching' air over the entire back hatch. Thus the downforce is distributed over the rear hatch portion of the car."



yea I agree you. The back hatch is still behind the axle. If you compress the rear shocks and leave the front stationary the car squats and traps air under the front lifting the front even more.

When they add the wing in 2018 you will also see the addition of the dive plane. It is all about balance. Check out the new ZL1L1E

Iconic

Hi Bob, I have something for you and I'd like your thoughts.

My Grand Sport came from the factory with stage 1 splitter and stage 1 spoiler. I upgraded the rear spoiler to stage 2 and left the stage 1 splitter as is. I guess I too have a stage 1 1/2, but in the reverse sense lol. I am wondering how this setup will handle at speeds over 150 mph at both Talladega and Daytona. I no longer have the stage 1 wings as I sold them, so my options are stage 2 spoiler or take them off and run stage 0 spoiler.

BEZ06

Hi Mike

You should have no problem at all. Have fun!!

Will you be coming down to Daytona this fall?

Bob

Iconic

As it stands now, slightly possible/mostly doubtful, as I have too much other travel plans booked. I wish to make it down again though, this time when Henry rents the track. Daytona is an absolute blast!

Bill Dearborn

I think if you are on a track that emphasizes speed over handling in corners then you want a minimal down force package. The C7 Stage 3 Aero adds a lot of drag that affects top speed but maybe more importantly slows the acceleration to that speed too much. At Daytona or Watkins Glen I think you would want a minimal down force package while at VIR I suspect you would want a full down force package which would help get the car through the corners faster. At VIR the lower and upper Esses and running down the roller coaster through hog pen onto the front straight eat up a lot of distance. Reduced lap times means spending less time in those areas Vs 5 or 10 mph top speed at the end of the two long straights which may be offset by entering those straights 5 mph faster.

Bill

BEZ06

Henry's Performance Driving Group event will be Oct 6-8 this fall:

http://performancedrivinggroup.com/events/


There will be a PCA OktoberFAST event Oct 27-29 - right now it only mentions racing, but they usually hold HPDE sessions as well. In past years the price has been a real bargain - last year it was $450 for 2 days, $500 for 3 days.


The annual Audi Club event will be held Dec 1-3 this year:

http://www.motorsportreg.com/events/...-valley-309907


And this year MVP Track Time will host a new Daytona HPDE Dec 8-10:

http://www.motorsportreg.com/events/...-school-389047


Hope to c'ya at the track!!

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Mad Dog 24

Bill when you were at WG last year did you have your wickerbill full up or down? Do you remember front and back straight speeds?