when you launch and floor the accelerator what RPM does it stop at, mine is like 2200,watching Utube I see there's is over 3000, am I doing something wrong? I press on the brake hard and then floor it, 2200rpm, doesn't seem to launch very hard

 

You have probably already read this,but the manual says this, about that:

Ensure the vehicle is in Competitive
Driving mode or any of the PTM modes.
. The brake pedal must be firmly pressed
to the floor, equivalent to a panic brake
event.
. While maintaining While maintaining the brake pedal, the
accelerator pedal is rapidly applied to
wide open throttle.

"If the vehicle rolls due
to wide open throttle or engine speed
does not exceed 3,000 Revolutions Per
Minute (RPM), release the throttle, press
the brake pedal more firmly, and reapply
the accelerator to wide open throttle.
. If the engine is cold, the vehicle may
be limited to 3000 rpm until
conditions are suitable for
acceleration."

 

The car launches great, got a 2.8 on the road the other day. Gotta say "competitive mode" , but my PDR says 3.0.

 

Either you are not in Competitive Driving mode (non Z51) or one of the PTM modes (Z51), or you are not pressing down hard enough on the brake (you really have to stand on it).

 

Mine will go to 3500. My best according to the car is 2.8. Not quite believing it though. Usually around 3

 

I have got a 2.8 time on stock tires on the street, but that is the dash screen timer. Now my PDR says 3.0, so maybe there is a difference in how they calculate. Either way that is still crazy fast.

 

I too have seen the discrepancy between time shown on the dash and what the PDR shows on replay. Anyone know why that is? It apparent on both zero to 60 time and track lap times.

 

The Cosworth PDR apparently uses GPS satellite signals to start launch. The GM Dash Test may well be using the array of precision accelerometers for the start since they:

• Have at least one accelerometer array in each corner as that it what sends control signals to the MRC shocks. It does that in all directs and the slightest movement will trigger.
• The Tesla Corp G-Tech Pro uses an array of accelerators to start launch. Their latest uses GPS for other things but states it uses an array of accelerometers to start launch. It does not need signals going 12,550 miles to satellites to define the launch start. (Note I have an early (24-year-old, bought when I built my street rod) version of the G-Tech Pro I used to make over 100 acceleration tests when setting up my ProStock Rod 4 bar link suspension and when modifying the 850 CFM Holley on its set back 8.2 Liter Big Block. The very aggressive launch in that 3000 lb rod with 16.5 section width Mickey Thomson tires in a rigid TCI tubbed chassis achieve over a "g" at launch. I made many mods and tests to stop the rear fuel bowl from going lean. Took many carb mods and installing an oxygen sensor in a long tube Sanderson Header collector to identify the problem of slight hesitation or bog. As that older G-Tech Pro instructions show, only need a precise acceleration and time measurement to generate all other needed 0-to-60-time, quarter mile times and speed!)
• There is a video showing a comparison of G-Tech Pro versus Dragy and the G-Tech showed a 10th or so quicker.
• GM does not have to pay a license to Cosworth to use their own signals!

I like the GM Dash Test because you can take a Pic of your car no one saying could be another etc.

I made many launches before I had ~1500 miles and used Lauch Control. I found it was essential to get the get consistent times on street pavement to have the tire tread hot. I accomplish that by driving aggressively in Z-Mode for ~10 miles. For the E-Ray that also gets the EV battery to 100% charge versus in other Modes it only charges to 80% Max. When I enter my 3/4-mile test road (safe, mostly farm fields both sides) I accelerate at WOT from a slow speed to 95+. Then I brake hard (~0.8 "g") that further heats the tire tread surface. I immediately perform the GM test. Without Lauch Control I consistently achieved 2.5 Seconds. The best without Launch Control was 2.4 seconds.

Using the same procedure, same street and pavement, 1/4 tank of gas, perfect weather, I achieved 2.1 Seconds. A fellow also posted his E-Ray Dash Test Pic with 2.1 seconds. The URL to his video is below, you can watch. He did the GM Test AFTER he did a number of aggressive laps on a Road Course. No doubt his tires were hot. I show Pic of my Dash Test (with my 11 lb passenger) as well as his Dash Pic from the video. I also show a Pic and URL of a Video of the test with a C8 Z06. It achieved the GM advertised 2.6 seconds.

They key is the front wheels allow the E-Ray to put all the 655 hp on the ground at Launch. In addition, the electric power front wheels have max torque at zero rpm! In the Hagarty 1/4 mile test, the E-Ray jumped the C8 Z06, a 700 hp RWD Ferrari and a Lambo about 1 1/2 car lengths. That 1st second is unbelievable! Hard to make that up in a 1/4 mile.

Most of the Car Mags subtract Dragstrip Rollout on their published 0 to 60 test data. I'm sure GM is also in their test. That can vary but they might be subtracting as much as 0.3 tenths which could be justified. Don't know.