J-Head Combustion Chamber Question

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Flying G

Flying G

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Greetings. Some of you have already commented on my cam/spring questions, so many thanks. These are the J-heads that go with that project. I've been doing some basic bowl/port clean-up, but now have questions about the combustion chambers...
>> There are ridges just below the valve seats on the quench side of chamber (see A & B in the photo). I believe these need to stay, but wanted to ask.
>> There is a triangular bump sticking up between the intake seat & the plug recess that drives me nuts (see C). Can I blend this in?
>> There's a raised step around the all of the seats (see D). These heads had a valve job ages ago, if that matters. Should this step be removed/blended to maintain a smooth surface from the seat exit into the chamber? Seems like that could only help flow, at least on the intake side.
Thanks!

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All that stuff can be blended in. ABC being in the combustion chamber won’t really affect flow, but by smoothing those out it will eliminate potential hot spots.
Smoothing D will help low lift flow, a little, if the valve seats are all ready finished be careful you don’t slip into them. Try putting an old valve in while doing the smoothing on D to protect the seats.
 
C and D need to be blended in. Leave the rest alone. Also you can gently lay back that sharp, pointy edge at C.
 
Smooth away. It may help reduce preignition.

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