racerns

Using Lightning Lap times for comparisons between different years is horrible due to different drivers and conditions. There was also a track widening and repave between the time the C6s and C7s were run. That track change was good for ~2 sec a lap on the full course. If you really want to look a magazine times then look at the Laguna times by Randy Pobst. There at least the C6 Z06/Z07 was run on Cup 1 tires and was over a full sec faster than the C7 GS run on Cup 2 tires.

RapidC84B

Those aren't accurate ETs for the C6Z and you don't use ET to measure raw acceleration, you use MPH. LT1 cars typically trap 117-120 where as LS7s will trap 125+

racerns

Umm .5 sec in the 1/4 mile is bus lengths, literally. You also really need to looks a 1/4 mile trap speeds as that would be more indicative of on track straight line performance. The C6 Z06 traps 5-9mph higher in the 1/4.

TrackAire

Point taken however quarter mile times don't support the C6z being that much faster either. 11.7 for z06 and 12.2 for C7[/QUOTE]

I'm not a hard core drag racer, but from the limited drag racing I've done on the quarter mile strip, a half second difference in ET may be 5 or more car lengths difference going through the traps. In my opinion, that is huge.

cvp33

Do you have video of your 2:08 lap?

grandsport2017

Yes I do.

2:08

A couple of 2:09s back-to-back

speedracernc

I'm not a hard core drag racer, but from the limited drag racing I've done on the quarter mile strip, a half second difference in ET may be 5 or more car lengths difference going through the traps. In my opinion, that is huge.[/quote]

I have never drag raced. I think you calculate the car length difference based on trap speed. The difference in trap speed equates to about 5ft/second. A half second difference would come to 2.5ft.
I may be totally off and hopefully someone knows what the right way to do it is. Either way I have become way off topic. ??♂ sorry

cvp33

i must have missed them. I saw 3 laps at around 2:11.

grandsport2017

Are you saying the 3 laps I just posted are around 2:11? Or the "chasing Z06" video earlier in this thread? I hadn't previously posted my "best" lap videos since this thread wasn't about lap times. In the videos just posted I'm using the PDR timer. Sorry, a bit confused by your comment.

cvp33

Sorry for the confusion.

1) You thought a C6Z must have had mods because it passed you
2) I told you he has minor mods and runs 2:04's
3) Other members were giving you advice on where you could pick up time, braking later, more throttle commitment, etc.
4) I was going to look over your best lap, compare it to the 2:11's and try to diagnose where you were losing time to a basically stock C6Z
5) I asked you'd to post your 2:08 as there's no reason to watch a 2:11 lap as the gap to 2:04 is just too large. In theory your best lap would give you less to work on to catch a 2:04 car and more lines to repeat.
6) You replied with a video marked 2:08 and another video marked "back-to-back" 2:09's
7) I looked through the videos and couldn't find the 2:08's or 2:09's. Maybe you can tell me when on the video the B2B 2:09's start?

If you have them and feel comfortable sharing I'd love to see them as I love track video, especially from VIR full course.....my home track. I thought the thread started as a question around a C6Z passing you and that he might or must be supercharged. Once it was established that he wasn't, I thought the conversation went to the driver-mod. If you're not interested in hearing feedback on how to pick up time, I totally understand and no problem.

For the record I have a 2019 Z06 and ran 2:07 (should've been 2:06 w/o traffic) at my shake down event. Ryan and I will be at VIR with track daze next month. We'll be doing some lead/follow for some sessions. I'm just trying to get smoother everywhere, if that leads to a better time, then so be it. I'd also like to not go off at 17 coming on to the front straight. It would be nice to not repeat that.

We were there a few weeks ago for a track rental. I was lucky enough to get some instruction from James Davison (Indy Car driver). He helped me pick up time everywhere, but especially turn 1.

Very sobering watching James jump in a 190hp FE2 car and start knocking off 1:54 VIR F/C laps consistently. Car only hits 140 on the straight so he's picking it all in the corners. You should've seen him through NASCAR and the uphill essess. Still makes we twitch.

Mordeth

cvp,

1) His videos above clearly show a 2:08.xx in video 1 and back to back 2:09.xx in video 2. It took me less than 30 seconds to determine this.
2) No idea what you are talking about with the rest of your post. You have a Z06 and aren't turning much better times, hence no need to post a thesis nor bizarre references to FE2 cars nor subtle references to the OP's "driver mod"
3) I realize you are trying to help and this is not meant to be personal at all

cvp33

All good. I didn’t see your 2:09’s sorry I missed them. The ‘bizarre FE2’ was to show that 190hp cars with 140mph top speeds can also crush 650hp cars driven by a novice. They’re called pro’s for a reason. I like the continuous improvement nature of road racing. Lots to learn and it never stops.

grandsport2017

Glad you found the videos. Must have been an error in the inter web tubes.

I see the conversation progressing differently. I was purely concerned with the back straight. I was going about as fast as I could go and the c6z still caught me. This is backed up by other LT1 drivers here in this thread and by this video of another GS driver hitting about the same back straight speeds on an amazing 2:01 lap.

The c6z caught up to me because it's simply a much faster car. If we're just considering the back straight and the c6z is right behind me, there is no driver-mod that will make it possible for a GS to go as fast as the c6z. If we consider an entire lap, the only chance a GS has to beat a c6z around the track is to maintain enough speed through the corners to make up for the straight line speed difference.

Very interested in hearing feedback. This forum is an amazing resource for drivers. I appreciate you taking the time to watch the videos and offer any advice.

I'm hoping to be at the March TrackDaze event as well. Would really enjoy meeting up and try to keep up with you two on track!

racerns

No, that is not how you figure it out. In this case one car finishes the 1/4 and then .5 sec later the next car finishes. What is the distance the 2nd car travels in that .5 sec after the first car finishes? A rough estimate would be to figure the distance 2nd cars travels over that last .5 sec. Lets say the 2nd car is averaging 115 mph over that distance, then it is traveling at 169 ft/s. So at that speed for a time of .5 sec the 2nd car would cover 84.5ft. That means when the first car finished the 1/4 the 2nd car was ~ 84.5 ft behind. Bus lengths

RapidC84B

You coming to VIR at all this year? I'm doing HPDE4 and TT2 in the Stingray. It'd be fun to chase you around.

racerns

I hope to, maybe in May or later. Too much going on with my daughter's gymnastics and possible college visits with my son before he makes a decision before May.

RapidC84B

Well that's obviously more important. I plan to do all the NASA VIR events this year (March, May, August, October).

cvp33

You did exactly what I was going to do with regard to aligning the two videos showing where his car was and where yours was. Unfortunately without telemetry we can’t see throttle, brake, steering and rpm. But we can hear it. All good. Hope to see some Vettes at track daze next month.

Poor-sha

I did a full data dive comparison in another video below. I also have some data of a lightly modified GS running a 1:59 at VIR. As I recall it had Hoosers, an APR wing, headers, xpipe, and the DSC/Tractive suspension. I still need to go through that data though and break it down.


While there is an HP and weight difference for sure I think the biggest difference with the C7 vs C6 is aero. The C7 with the stage 2/3 aero just really slows down at higher speeds whereas the C6 is a lot more slippery. However, you're trading more drag at high speeds for more confidence in the corners.

cvp33

Thanks for that Sean. Hoping to see you out there soon. Been too long.