Timing with Hypereutectic pistons

First off 10/1, on a teener is hard to get.
If you really are gonna Zero-deck it,then you will need to run closed chamber heads,
and and a thick (.035,minimum) head gasket.
This is because, the math says 10/1, on a 3.95 x 3.31 teener,is a total chamber volume of 73.85cc.Since the pistons will have 5cc eyebrows, and the gasket (FelPro.040) is about 8.5cc, and the deck is Zero cc,that leaves just 60.35 for the heads, and almost the only way to get that is with closed chamber heads.Couple that with,the 320 hp goal, and your heads just became very, very,expensive.

A cheaper, easier way to a 10/1, 320 hp, with a teener, on the street especially, is a long-arm crank.
Say a 3.58 stroker..This requires a total chamber volume of 79.88, and heads+deck of 66.4cc
Or a 3.79 stroker....This requires a total chamber volume of 84.56, and heads+deck of 71cc.
Or a 4.00 stroker....This requires a total chamber volume of 89.25, and heads+deck of 75.75cc

Another reason to think this through, is that the XE268, while not being super-soft off idle, that 2400TC could make it seem so. "Could", being code for "will", IMO.
To get the off-idle torque up,you can go to a shorter period cam,(thus increasing the Dcr), or you could go stroker. The long-arm will do three things for you;
1) plenty more low rpm torque, and
2) allow a longer period cam. before dropping the Dcr into the basement, and
3) make Scr and head selection(with bigger valves, and more flow), much easier.
These pluses,lead to a dynamite street engine, with tons of low-speed torque, a very strong midrange, and a lot of higher rpm power potential. With this new-found torque, you can step down a cam size or even two, or not, making the 2400TC do-able, and 3.55s( or even 3.23s) also doable; making hiway touring a possibility again .
So here's how that might play out,(remember I'm talking a streeter here);
The money you didn't have to spend on rear gears and a TC, will buy you a stroker pkg.
The money you didn't have to spend,maxing out the teener heads, will buy you a nice set of iron street-ready heads.
The money you didn't have to spend on machining costs, will buy you a Suregrip and some fat tires.
If you chose your stroker kit,and heads wisely,(and there's some really smart guys on FABO to help you with that), you will end up with a really killer 3000 pound streeter, that you can lite up the tires with, in maybe three gears; and still drive a 12 hour day, to three states over, for a weekend car show. I call that a win,win,win, winning combo.
Well that's my opinion, anyways.

Oh yeah, the engine cubes math out to; 351,372,and 392;if that make the decision any easier.
Oh yeah, another thing, none of these will make 320 horsepower........Unless you seriously
choke
them
down.