Had a similar prob with mine , used to drop 1 pot when it got to operating temp, clean the 2 temperature sencors at front of the engine .
Good luck Brad
Have a GTR 33 crank that has a decent mark on the nose where someone has fitted extra drive of sorts, its just a spare for myself , paid $275 , if you are interested . Brad
They have a Dyno now a days, and Robbie knows how to use it . We take the Torana GTR there for tuning, started with 175 hp and have ended up with 198 at the wheels . Reccommended