The engine now sings! ……lets recap how we got here…..
Since last summer, the following has been done to improve runnability and performance.
So, you can imagine my disappointment when I started to drive the car this summer and the engine felt lazy, there was a dead spot during acceleration and I would sometimes have an intake misfire under light acceleration. I started to go down rabbit holes thinking of causes and it was during my investigation of any potential manifold vacuum leaks that I posted to jaguar forums and received some interesting advice. Grant Francis is a well respected and experienced voice on the forums and he suggested the following:
“Lift that timing, as I mentioned, and see what happens. The PreHE can run some serious advance with NO issues“
He also provided me with this write up on setting the timing with the Jaguar V12.
I took his advice and started to increase the timing advance. The idle sounded better, the acceleration felt lively and the engine started to sing. I didn’t have the courage to keep increasing the advance until it started pinging and then back it off, but it sounds and feels much better…..thanks Grant!!!
Below is a video of the car accelerating so you can get a sense of how it runs and sounds now.