If you've got a 99 GS300 and a similar year Aristo 2JZ-GTE VVTi engine set with a non-immobilizer ECU, doing that swap is so fucking easy that I can't help but recommend that first.
If the only thing you're short is the non-immobilizer ECU, find one, and still do the swap.

With a basic bitch cheap front mount IC, and a similarly basic 3in exhaust that combo will be good for ~375whp barely trying, and with near-OEM levels of reliability and driving ease and everything else. Boost controller, catch can, and a few basic things like that and you'll be able to drive that car on road trips, have the A/C working perfect, and just have a nice kick ass Japanese touring sedan with modern-day levels of HP.
When the stock turbos die (they almost always die) decide from there on your path forward on doing a single turbo/built auto etc with the stock GTE block which is almost strong enough for your HP goals with 100% stock internals.

While enjoying all of that, I'd take the 2JZ-GE VVTi block you'll have left over, and build that shortblock on the side with your 3.4L kit when time/budget permits. You can easily use the GE block as a base for this, and install the 2JZ-GTE VVTi head to it when the time comes.

 

If you've got a 99 GS300 and a similar year Aristo 2JZ-GTE VVTi engine set with a non-immobilizer ECU, doing that swap is so fucking easy that I can't help but recommend that first.
If the only thing you're short is the non-immobilizer ECU, find one, and still do the swap.

With a basic bitch cheap front mount IC, and a similarly basic 3in exhaust that combo will be good for ~375whp barely trying, and with near-OEM levels of reliability and driving ease and everything else. Boost controller, catch can, and a few basic things like that and you'll be able to drive that car on road trips, have the A/C working perfect, and just have a nice kick ass Japanese touring sedan with modern-day levels of HP.
When the stock turbos die (they almost always die) decide from there on your path forward on doing a single turbo/built auto etc with the stock GTE block which is almost strong enough for your HP goals with 100% stock internals.

While enjoying all of that, I'd take the 2JZ-GE VVTi block you'll have left over, and build that shortblock on the side with your 3.4L kit when time/budget permits. You can easily use the GE block as a base for this, and install the 2JZ-GTE VVTi head to it when the time comes.

That would be a lot cheaper route and get the engine swap done faster.
Okay I have a couple questions.
How would I know if I have a non-immobilizer ECU and if I do decide to take this route instead of doing the full rebuild all at once, you think a CXRacing kit would work?

Wouldn’t the rods start to bend once I decide to do a single turbo build and get to 800whp with E85, PT6466, GSC S1 Cams, Cast Manifold, and SP QSV? From what I read the rods start to bend around 500tq and I feel like that combination would make over 500+ and have a lot of torque at the beginning of the powerband.

Wouldn’t the GTE be a better/easier block to build instead because it already has the turbo oil feed holes and oil squirters?

I never thought of building the GE block. Does it matter if it has over 280k+ miles?

 

Hi, how about the shifter change? I have a gs300 with the Aristo gte + tranny, but the gs300 shifter and instrument cluster. My shifter is stiff and the gears are not in the right place. Any good way to solve this. I do have the aristo shifter and instrument cluster available also, but I don't know if they will fit the gs300 center console. The ac piping for the rear vent is in the way of the rhd aristo shifter, if installed in the og rhd position.