yup Have a 2jz that makes over 600whp on the stock rotating assembly sitting on the dyno right now. It has made that power for 88K.
The LLT and LNF have a similar parts list, and most of the rotating assembly is plenty strong for the task. We have been well over 400whp for a while on the LNF and those pistons are cast as well.
Both motors have a forged steel crank, and sinterforged rods. With full floating pins and oil squirters to control crown temps, the cast (most likely hypereutectic) pistons are likely alot stronger then you give them credit for.
As for fueling, it's just a matter of PCM access. When you run out of injection window@max rail pressure, you just need to add a PFI rail. We have been running our prototype on it for a few weeks now with significant upper rpm gains.
DI+ PFI secondary=win. Esp if it uses a secondary tank fulla E85
THis motor will make good power on boost. I'll bet money that as long as detonation stays out of the picture, the weak link(cast pistons) will be strong enough for well over 600hp.