Case Porting & Epoxy - Opinions? (With Pics)

[Dartman]

this all plays a role in how much upper case work you do when adding bigger ports in aftermarket cylinders
also bore and stroke combinations all effect the primary compression ratio

 

[Pro-pulsion]

Thank you sir, now what about sealing the cases on reassembly? Do you have any high quality sealant you guys would recommend? I was thinking something like 3 Bond such as Yamabond or the like. Anything more preferred?

 

[Blue]

Yamaha bond. Honda bond is all i use. Never had a sealing issue but difficult to remove at overhaul intervals.

 

[Pro-pulsion]

With regards to the intake tract and putting the little scallops into the top side, is there a rule of thumb mathematically speaking for sizes, percentages or direct equivalents? What I mean by this is say just for ease of numbers, we had a bore of 100mm, the exhaust port is 50mm and we open that up to 68% of the bore (68mm). If you were to calculate the 18mm oversize it works to about a 32% larger port window. Would you then use that 32% as the rule for for diameter on the upper scallops? To further explain that thought, I mean would you make them 18mm in diameter or is there no real rhyme or reason for dedicating a size.