@MKVASMR yes i thought this too but apparently that's not the case lol ....I totally get why it looks like one solid piece—the machining on these engines is actually very high quality! But if you look closely at the "timing chain" end of the head (the driver's side on a UK car), you'll see where the Camshaft Adjustment Housing (the big aluminum part that holds the chain tensioner and N205 valve) bolts onto the main Cylinder Head.
Even on a BYD, there is a hairline seam right there.
it even says this on the Elsawin software "Apply a small amount of sealant to the transition points between the camshaft adjuster housing and the cylinder head.".. i even asked chat gpt and it said :........Why you don't think it's two pieces
Looking at your BYD from the top, it looks like a single block of aluminum. However, on the right side (where the timing chain and the N205 solenoid are), there is a separate housing bolted to the end of the head.
The Seam: There is a tiny vertical line where that end-cap housing meets the main cylinder head.
The Step: Even if it’s only a 0.01mm difference in height, the rubber gasket can't always "crush" enough to fill that microscopic valley.
