I couldn't readily find a smaller sample of the same image in its entirety so the following "preview" is in two parts:
The full sized version is still in one piece. I've seen this image (or a similar one) elsewhere, but never at this size; resolution is 12000 × 3888 and the file size is 8.3 mb. The following is a direct link to the image:
Mclaren Technology Center Lineup
The file path shows that the image is originally from the Mclaren Automotive media website but I found it in this article on the Mclaren Newport Beach blog:
Mclaren to Showcase 50 Years of Racing...