4.2 litres seems right in a Jaguar. So what if it's a few more pistons; and a supercharger; and a homemade injection system, and exhaust, and some minor stretching exercises on the frame tubing. And some paddle shifters. No Big Deal. I get to weld and solder and it's brain exercise. And hey, don't fuss at me. It makes your pristine original worth more!
Now if the editor can make the upload process right my pics!