Judge Ito

Mike. I have seen some japanese engine builders round off the sideseal instead of tapering off the sharp edge. I trush a tapered edge before Ill round off the sideseal. I feel there is still room for error with a rounded sideseal tip. Eventually the sharp edge will eat away into the rounded sideseal and chew up the rest of the sideseal.

amp

how bout doin both..

or would that be overkill...

pengaru

rounding off the seal would also compromise it's sealing abilities when it's not over any port (during compression).

amp

thought about this as well..

but correct me if im wrong...

but i believe mike was referrin to chamferin the edges of the side seal...

without compromising height...

pengaru

Well, this is what I imagined he meant considering the direction the seal is traveling when it encounters the closing edge of the intake port:





which would cause a leak... mike can clarify if the image illustrates what he meant or not.

amp

i envisioned it this way...

for the rounded edge to be only the portion that ran over the edges of the intake port...

elevated view at the end of the seal..

Judge Ito

Pengaru's drawing is correct. And that is the reason I wouldn't round off the sideseal. I would not want to sacrifice sealing capabilities out side the closing edge of the port.

pk797

Yeah, I agree with the Judge on this. By chamfering the ports your essencially fixing the problem at the source. To start trying to alter the side seals would be to create a new one.

PK797 NYC

kahren

i dont think it was the problem where they knew about the sideseals getting damaged because they ported too far, but the lack of knowledge that the sideseal can get hurt if you port too much. i am sure most people only think about the corner seal not falling in or its little insert. if they knew the sideseal could get damaged once you go passed a certain point they would probabaly just not port that far out. if you calculate the length from the rotor housing once its placed on the engine to the sideseal inner edge, its about .3 of an inch so porting out any more then that will hurt it and this modification ITO was talking about will be needed if you port more, but then again you are already getting pretty close to where the corner seal insert would be completely exposed. unless you are running solid corner seals i dont see how you can port much more out to get more air stuffed into the engine.

David0ff

thx for the tip , when i port in a week or 2 .. ill round off the port closing