project came to light because we were looking for a way to increase the
performance of the stock cylinder heads on the Mercedes Benz M113 5.5L
Kompressor motors. We had a set of stock heads flow tested and found that there
was alot of room for improvement.
The Stage 2 heads
involves a complete valve job and porting work as well as a pair of our custom
We also replace the heavy, stock valve spring retainers with a set of our custom
made titanium retainers. The stock retainers weigh in at 18.01g while our
titanium retainers are just 10.22g.
It takes approx 1 work week to
complete the work on the heads
Here is what the stock
heads look like right after you take them off your engine block.