Tracy Crook wrote:

Ok, so I finally took my spare engine apart (that I've had sitting in my
garage from before I ever had my airplane flying).

Rotor housings seem to be in a lot better shape then in my running
engine. Which brings me to my question:

Is any exhaust porting recommended?

This is a 1986 13B NA. On my running engine I expanded the exhaust ports
as much as the steel sleeves allowed.

Finn
    

I would not mess with the exhaust ports unless you REALLY know what you are
doing.   I fully admit that I do not when it comes to exhaust porting, but I
don't think there is much to be gained at 6000 rpm or less.

Tracy Crook

Thanks Tracy.

Well, I might need to go up to 6,500 rpm to get above 210 mph (eventually, with reduced cooling drag and tuned intake and exhaust).

Any other bids? Leon?

Finn