Thanks fellas for the responses. Here’s an update to answer some of your questions:
- I used a straw to check TDC versus the crankshaft damper. It appears to be fairly accurate but of course there is the slack in the timing chain to account for. I DID turn the engine back then forward again to try and eliminate the slack so again - the markings do seem accurate.
- This is the original damper but the crankshaft was sourced from my spare engine, checked and fitted as the original crank had spider cracks shown in the magnufluxing. so it WOULD be possible that the damper markings for this engine be off a bit but they are after all keyed to the crank. In other words - I’m fairly certain it is reasonably accurate.
- I outsourced the machine work but I assembled the engine so I guess there is no option to check with the ‘builder’ unless I interrogate myself. LOL.
- The intake side appears to be spot on. The only question now is the exhaust side. The checking tool fits perfectly at 4 degrees AFTER TDC. so the exhaust side would be timed a bit late.
I could remove the sprocket and shift it to adjust, but now I’m wondering if this timing would be considered optimal for some reason. I truly don’t understand valve timing theory. I supposed I could have swapped the parts from side to side, but given that the intake side seems dead-on I’m now wondering if this is simply how it was setup at the factory. The sprockets ARE original to this engine, and I don’t believe they were removed from the center sections as the teeth appeared to be in good condition so they were cleaned and re-installed with new timing chains…
In summary - we know 4 degrees after TDC is not an interference setting, could it be this is the way it was set at the factory for optimal performance?