I was browsing videos of these cars acceleration and I have come to establish that the GP is a full 3 seconds quicker to 200 than a fJCW

JCW is roughly 0-200 km/h (120 Mph) in 23 seconds

https://www.youtube.com/watch?v=YX_Km0D11oE

https://www.youtube.com/watch?v=HyrVlmzZF_s

https://www.youtube.com/watch?v=FOAbFbBGsrk

JCW GP is roughly 0-200 km/h in 20 seconds.

https://www.youtube.com/watch?v=vIJzjTUJvcA


Is this purely down to the 5 kW extra, the weight saving on it compare to the Coupe/Hatch is not that substantial.
Yes it has stickier tyres so that helps in the initial phase but if you look at the videos 100-200 its still noticeably quicker.

To get this performance do I simply need to change the downpipe because I believe theres 5-10 kw in it?

 

There isn't a power difference. 211hp (metric) is 208hp (english). I don't know if the gearing is any different, but as the GP sits lower, it would have a bit less frontal area. That would work to improve the top end.

 

I'm at work, so I'm unable to watch the videoes, but were these 2 cars tested on the same track, same day, about the same time and by the same driver? If not, then there is a lot of variables that can play into a 0-200 km/h run.