I have seen this before but on a 2 stroke,that was most definately a spark plug starting to break up. I'm with the hard carbon/gasket/butterfly screw theory unless your air filter only stops bricks Looks ok to clean up and keep running though
1965 Belvedere 2 426 Wedge.
Climate change,global warming,the biggest tax raising scam ever devised by man for mankind.
Defly debris damage- trashed enuff 2-strokes in my early days of mechanicking to recognise the signs!!
I've had far worse than yours Dave with no further problems, long as it ain't bent a valve or dinked a seat (not a problem on 2-smokes o'course!).
Though i guess on a real hi-po engine marks like that could cause hot-spots and pre-ignition?
I suppose even a small bit of something dense would make impact craters like that given enough velocity.
OK well that has all been VERY helpful chaps. Thanks!
I will check the valves and seats in due course. I will also have to stop running up the strip with no air filter on.
Shame because there is a definate improvement in top end power when running with just the baseplate. I WISH someone would make a six pack filter just ONE INCH taller so that it will still fit under the R/T hood but flow enough air for the top end charge.
I need 3 inches TOTAL otherwise it hits the hood. In fact it might hit the hood anyway. The six pack intake is mighty tall. The stock size K&N filter which I have is 2" tall and it does not flow enough. Better than stock but not enough.
Two filters one on top of the other is too tall. But I think I might just get away with a 3" if they are making one.
I will look up that last part number. I checked this out just a couple of months ago and there was only the stock height filter.
Come to think of it I emailed K&N about wanting a taller filter. I wonder if they took notice??? Surely they wouldn't produce one on the evidence of one e-mail? No. I doubt it. But if it fits under a R/T hood it will be a big step up for all us six-packers.
Frame 15 definately suggests FOD. You can actually see craters, though how something could get pushed onto the surface that hard and still manage to leave a raised area around the impact I have no idea. I have seen damage on cavitated marine props like this before, but with something swirling around in the ocean I have always assumed the craters were unrelated to the erosion.
I have no idea why I just said all of that, I'm really not helping am I?
If anyone has a sunseeker that needs a service, I'm your man!