TDI Engine Pictures: See-Through Designs

Hi.
I once saw a picture of a TDI prototype with a turbocharger and transparent cylinder liners. It was probably intended to allow observation and optimization of the combustion process. What was also striking in the picture were the extremely long connecting rods.
Unfortunately, I don't remember where it was, and I'm not sure if anyone else knows where I can find that picture again.
Thank you in advance.
Cord.

G-charger instead of or in addition to a turbocharger?

Just one G-loader.
It should finally be a GDI .