Hi Adrian, can’t really say for your 120, I’m no expert and I don’t know your engine, but I ran with it in my 1HZ 80 soon after I bought it. The engine had been mistreated by the previous owner, and run with an economy weight foot...
With some 2 stroke in the oil burner and driving it like a rental, she picked up quite a few horses.
It drove like a slug when I first had it, but after 3 or 4 months Italian style tune up, she’s as lively as she’s ever been. The 1HZ is the sluggish of all Land Cruisers with no turbo, but the advantage is there’s no EGR to block up with soot - it’s too old school for such mod-cons, and that’s a blessing.
I‘d say give it a go, I’m sure it will do no harm if everything else about the engine is in good order. You’ll soon know if it likes it, and you can always stop using it if it doesn’t.
Mine went instantly quieter and a smoother run, it was really noticeable at first, and after it had cleared itself of gunge, I stopped using it because it seemed to make no more difference.
There‘s 462k km on the dial now and it’s still going strong... touch wood... (oooh, can I say that these days?)
Job done for me.
Best of luck... and post up your findings if you give it a go...
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