Ok, as mentioned above I have today been to the weighbridge.
Below are my calculations based on my test in comparison with Vauxhall....apologies if boring
Original Vauxhall Test:Kerb weight when Vauxhall tested was 1643kg. This included a full tank. No driver. No luggage. (Your handbook will say 1718kg but if you read the little note at the bottom that included 7kg luggage and a 68kg driver).
To this they add 200kg to allow for an average configuration and includes the driver.
Total - 1843kg.
With this they get a 0-60 time of 9.2 seconds.
Me and my Omega:I got the car weighed in exactly the conditions as I did the test in...virtually no petrol and with my full size spare in the boot and not including me....car weighed 1647kg. Add to this my 'ample' frame and the weight jumps to over 3000kg. haha just kidding
with my weight it goes to 1761kg.
With this set up I got a 0-60 time of 9.44 seconds.
Conclusion...The weight difference between the two test weights (mine and theirs) is 82kg. I work out using 0-60 calculators online that 82kg is worth 0.322 seconds.
Therefore I can conclude that the times for comparison are...
Vauxhall - 9.2 seconds
My Omega - 9.76 seconds
A difference of just over half a second slower compared to Vauxhall's original figures.
I've learned lots on this thread and I think I'm happy that the half a second could be made up.
Advantages they had was using the test equipment they had available, the dead flat ''grippy'' straight they used at their Dudenhofen facility in the Fatherland (I looked at my place of testing en route to the weighbridge and im starting to convince myself its a slight incline!) and getting really nerdy, look at humidity/airtemp etc.
I think one massive key thing (as the guy from Vauxhall also said) that I would need to perfect that launch especially as that was only my 2nd attempt and I'm sure I could have got a bit more out of it.
As mentioned before I'm not going to do any more tests. Although i'd have dearly loved to have matched the original results I'm quite happy with the results I did get and in the knowledge that I could probably bring that time down if I was to do all the things above. but I'm not going to be doing anymore brake torque starts lol
Getting well under 10 seconds. That in itself I thought was a challenge.
So I can put this to bed now. Cheers for all the comments along the way. good and bad lol
Now. to STEMO's all season tyres.....