I have an US spec 1985 FJ60 with all the original equipment, smog etc... I had done everything I could to tune it up and was still not satisfied with its performance. Then I ran into an engine builder who had been a certified Toyota mechanic back in the day and he recommended I set the timing to 18 degrees advance at idle. This is significantly higher than the factory spec but I gave it a try and man what a difference. You will need a timing light with an adjustable strobe.