I woudn't go to .060" over, power gain doesn't amount to squat.
I would also get the engine together and running NA, with a fuel system built for boost on e85, first once the bugs are sorted out, add boost and a megasqurit.
I'm seeing the viability of going only .030 over with the turbo. I think i would for sure go .060 NA, but you are probably correct and adding another pound of boost would add 5x the power compared to the displacement from .030 more bore. Pointless for the extra strength/ peace of mind. The walls are thinner than I expected after I cracked the engine open for the first time, not really sure what I was expecting though.
However, I doubt the cylinder walls bored .060 would be the point of failure if the engine was tuned to the ragged edge. Which, theoretically, with forged and balanced internals, a capable fuel system, and detonation kept at bay with all the tricks- would be more power than would be realistically useful in any environment that I can think of. Besides a dyno
The 35/40 hybrid was single scroll IIRC but the spool was amazing. Came on super quick; almost too quick and hard. It was not very linear, but I learned to drive around that light switch aspect of it. It was probably the must fun the car ever was. The straight 40 was twin scroll and the boost came on mitre gradually as you would imagine. Thing pulled like a freakin freight train up to. It was probably a little north of 600hp at 3.2 bar of boost.
3.2 bar??? As in ~45 psi? Holy cow... that's equivalent to somewhere around a 10 liter NA engine, right? I guess 600 or so sounds realistic when you think about it that way.
Sounds promising. Forgive my ignorance on turbo matters, but are larger turbos such as these efficient/effective at low boost levels? From what I've seen people push 30+ psi on these regularly, as they were designed to do on the diesels they came on. I know large turbos will be more efficient at higher boost, running cooler and all that. But at lowish boost, say 6 lbs on this HX35, would it make sense to run this turbo? A small turbo should spool faster in theory.
Not that I'm that concerned about spool too much. High compression and the twin scroll housing will make it work whether it wants to or not
A note on the twin scroll housing. Current idea is to get one of those weird twisty headers with two collectors and fab two down(up?) pipes to the turbo where a fancy flange will bolt them to the turbo. Thinking the turbo will work best on the passenger side. I know it's been done, but I have no idea if pipes will fit under the oil pan on a stock suspension jeep. Shoulda measured before the engine came out. Oh well. I'm seeing the advantage of a 2WD jeep now.