New guy rant and porting

[cus_deluxe]

My (limited)understanding is that the little bit of turbulence from the rough finish helps keep fuel atomoized?

 

[TheTone]

Exactly.

 

[Ccarignan]

Yeah, that was my understanding, to leave the intake dimpled and polish the exhaust. Looking at the new cylinder, I feel like I’ve seen this, to avoid having to put the piston backwards by putting fingers into the cylinder outside the width of the transfer, I can just bridge between the transfers right? Red lines on picture.

 

[Ted Jenkins]

Those who have built 2 stroke engines for a living know all to well that some times an engine porting can be polished to death. Now that 2 stroke engines are all but obsolete it still is interesting to play around with new designs. For most part a 2 stroke does not depend on the porting to help mix fuel and air together. The finish might make a certain engine run a little richer or leaner depending on many factors. The biggest issue is what the finish does. It allows fuel and air to move slower or faster depending on how and where the porting modification is. One factor that many know is the effect of a larger port that suddenly or gradually becoming more narrow or smaller will accelerate the air flow speed which some times is desirable. For those that play golf know that a smooth ball will not perform well, but a ball with divots on it will travel far and smooth. Same with porting. A consistent finish that has little dents in the finish will out perform most anything because the finish will cause the air to roll like little tiny twisters around the finish which acts like little ball bearings. The air and fuel mixture can then travel a little faster into or out of the combustion chamber faster thus creating more power. Thanks

 

[Ketchup]

A bridge port should work fine. Usually they are angled slightly towards the intake like a 7. There are lots of pics out there. Take your time and you should have a beast!