G-Tech results with my new C6

[self1]

I just got a new C6, and with 1,000 careful miles now on the clock, it seemed an opportune time this morning to take it out [by itself, to a private location, away from public streets and highways] to gauge it's initial performance, using my G-Tech SS.

The average of three runs was: 13.39@109, with very good consistency (+/- 0.08 sec), but terrible 60' times (2.28 seconds)

Technique:
Granny shifted,
Did not warm tires,
Launched at about 2500-3000 RPM
Left AH/TC enabled, but still got terrible traction and some wheelspin.
Altitude sea level, temp 77, humidity ~60%


I will be using the car for standard fun duty -- running around on weekends, driving to work, taking on trips, etc, and not for any kind of competition, but I still would like for it to measure up to it's performance potential.

A question for some of you experienced folks: Is this about what I should expect, given the conditions/limitations? Or is mine a little off? It feels seat of the pants okay, but the G-Tech is indicating only about 240HP/255Tq, with estimated 3500lb load.

Thanks,

[self1]

By the way, anyone interested in shifitng your C6 quickly, I found that the 2-3 upshift on my car is very peculiar under rapid acceleration conditions... when tooling around town, or 'normal' use, I have no problem at all while gripping the shifter like I normally would: using all fingers as well as my thumb, all wrapped around the knob.

But in order to get a quick and sure 2-3 shift while pushing the car harder, I have found I need to just use the meaty part of my palm ALONE, fingers floating over the knob, but not touching it, and push forward, letting the springs/gating/alignment all take care of itself. I must be expecting the gate to be somewhere other than where it really is, so when I try to use my 38 year-old habit of directing it, from shifting "H" gate four speeds, I can't find third!

Maybe it's just me, but I'll bet some other 'old dogs' might have a similar experience, too. Luckily, I did once put a vertical gate shifter on my '67 Camaro's M-22, so the needed C6 2-3 'hand smack' <chuckle> was not as totally foreign for me as it might be for others.

[Sunday's Gold]

self 1 the HP and trq. you recieved from the G-tech is too low...
My C6 with A/T and Borla exhaust with Cats dyno at 342hp and 342trq.

[self1]

Originally Posted by Sunday's Gold

self 1 the HP and trq. you recieved from the G-tech is too low...
My C6 with A/T and Borla exhaust with Cats dyno at 342hp and 342trq.

Thanks for the reply. Yeah, the G-Tech seems awfully pessimistic compared to dyno and also to mfg specs just about every time I have heard of it being used.

I have, however, heard (and experienced) pretty good results for it's 1/4 mile ET accuracy and speed determination, as well as other timings, i.e. 60', 0-60, 330', etc.

The main thing that occurs to me from looking at the numbers I posted is that I am losing a ton of time "in the hole", i.e. people claim a good run on a strip with this car yields 1.7-1.9 sixty foot times. Since mine were around 2.3, that is about 0.4-0.5 off of optimal, which with no other improvement in mid or top end, yields up an easy sub 13 sec result if I could get 'teething'. I haven't hooked up the G Tech since my initial runs, but I did accidently leave the traction control in 'competitive' mode while showing one of the coworkers the car's capabilities (I've sure been popular for lunch lately <chuckle>), and WOW, it really is easy to overwhelm the tires on even good pavement all the way through first gear. The car tracks very true, so I never had to get out of it, or worry about it getting squirelly, but if you just keep on the gas and wait for the car to catch traction, you are spending a lot of time spinning the wheels. I don't like the idea of pedalling either the gas or the clutch on launches, so I may just 'walk' the thing off the line at lower RPM, and then floor it only once clutch is fully out. Again, I am not into dragging or abusing the car, just interested in the best way to get acceleration on launch without muss or fuss, on the few occasions I may want to.

I am really loving this car, for just cruising, for highway, even around town, the clutch is so light it doesn't fatigue the leg or feel like a hassle to mess with.

I have experienced the failure to go easily into first gear at a stop that some have complained about, maybe four times out of many hundreds of stops, but with this car's torque, just go to second and no problem. The only thing that worries me is if it should get worse through break-in (unlikely) instead of better (likely).

[MoeJr]

The GTech will read about 3-4 mph high in the 1/4. If you take your 109mph and -4 that is 105. 105 in the 1/4 will get ya into the 12.6-12.8 range with traction and that is right about where a C6 is supposed to be.

[self1]

Thanks for the reply! I knew I was out to lunch SOMEWHERE, because if you plug the top 1/4 speed plus weight into some of the drag calculators out there, it says I should be quicker and have a lot more HP than I charted, but I think all of those calculators assume pretty near perfect (linear) acceleration including off the line, so knowing that my losses are largely in the sixty foot zone, the rest all starts to make sense. I sure miss the old test-n-tune nights when we had a strip right down the road, but now I would have to drive an hour or so to get to a proper track. Maybe once I have about 12-15K miles on the tires, and don't mind losing some rubber, I'll head to the track and try to do a proper burnout and get max traction off the line.

That would also let me "tweak" the pitch correction (blindly set to 4.0 now) and check my G-tech against real timing gear.

[AintQik]

When fiddling with your G-tech, are you launching the car without any driving aids on? Press and hold the traction button untill it beeps and says everything is off. Just turning the traction off or leaving it in comp driving mode will kill your 60'. You really need to leave this stuff off and figure out the sweet spots in the car. The car pulls too much timing when it gets squirrley. Just leave it off and learn to launch the car. My best is a 1.96 on a prepped track. Could only be achieve by slipping the clutch. Stock I trapped around 106. Now I get slightly more mph

I missed 3rd all the time. Heck, I even miss it now sometimes. I think it has a bunch to do with the clutch. I think it really hates 6k rpms. I also do the ole slap into 3rd method and it works most of the time. It still won't go into gear when I am a. trying to look cool, or b. in a really tight race on the track. Sounds like driver error to me but I'm still going to blame the car.

Oh, one other note I have experienced in this car at the track. Most of the time I don't heat up street tires. I go around the burn out box. Here at ATCO the waterbox is across the whole friggin staging lane. So, I had to light em up to get the water off. Low and behold my 60' dropped considerably. I did some back to back comparisons and everytime I did a short burnout my 60' was much quicker. Just something else for you to try.

[self1]

Originally Posted by AintQik

When fiddling with your G-tech, are you launching the car without any driving aids on?

Yes, I wanted to get a couple of months of driving in various conditions before I take off the 'nanny' -- I just don't want to end up like the cub reporter who barrel rolled a new Z06... call me chicken...

I also do the ole slap into 3rd method and it works most of the time. It still won't go into gear when I am a. trying to look cool, or b. in a really tight race on the track. Sounds like driver error to me but I'm still going to blame the car.

Sounds like my own experience, reminds me of something from back in my motorcycle days: Smooth/relaxed is faster (even though it doesn't always feel like it); Rough/tense is slower (and dangerous)...

Most of the time I don't heat up street tires. I go around the burn out box.... I had to light em up to get the water off. Low and behold my 60' dropped considerably. I did some back to back comparisons and everytime I did a short burnout my 60' was much quicker. Just something else for you to try.

Good tip -- I also generally just drive around the bleach oops water box because I run standard street tires and it rarely helps, so if the runflats can get stickier with some heat in them, on the once or twice a year I actually get to a real track, I will experiment with warming them up. Thanks!

[Nick Smith]

i switched to a dual disc carbon clutch and a breathless performance short shift not only can i hit third alot better but also 60' time is at 1.98 from a 2.03 before but i have also only had the car bout a month and a half so i am sure that time will get much better