Howdy Tony! I've been messin' with the Tiger's allot lately,, much more than what I decribed in that post to Rodney.
With the help of TimD and a machinist in Ohio We made up some head button's in the .17 , .18 and .19cc volumes.
Along with those, I cut the crank induction to 214 degrees (open 30deg ABDC and close 65deg ATDC) and have cut the custom head buttons to allow up to a .010in sleeve shim to raise all the ports and still have .008 headspace.
Also found a GadgetCraft Carbon Pipe from a fellow boater
like you were using and that "combo" will really light them Tiger's Up
There is a new "learning curve" using the low volume button's as I found out. It involves running the motor "fairly rich" and restricting the waterflow to get things hot enough to use all that fuel,,and when it does,,YEEHA!
Oddly enough the engine likes 184deg exhaust port timing with this set-up and I've tried many, all the way down to 175deg.
The "front bearing leak" you mentioned is not something I've noticed,, I do use a Swiss bearing in there and and change them in mid season.
I also put two ounces of "castor" in a new gallon of 60% fuel it will help with the poor seal in the crank rotor.
I've only used the carb that comes on the "newer re-introduced" motor, it has a different carb than the earlier models. But I did find out that it was hard to get the engine "rich enough" for the new mods with out the needle falling out. TimD suggested cutting the tip of the needle off (about "1" to 1.5mm)and I promptly did.
Also took the boat and engine to a District race to test it (Not Recomended) but finally found it and it did help allot,,(didn't lose anymore needle's)
It's Great to here from You,,We need to talk more
Jerry