Hiya Dave,
Welcome to the club
.
My car when it was running had an auto box, I was told at the time by Silvia Engineering, that the auto could handle over 200 bhp at the wheels. It won`t
, plus Silvia Engineering are no longer running now
.
TBH, I wouldn`t go much more than 170 bhp, with the auto. I spent a huge amount of money on mine and got the power up to over 230 bhp, even had the gearbox reconditioned, just to be on the safe side. It was fine from a standing start, 0-60 in around 6 seconds. But if you used the kick-down, the engine would red-line, before the gearbox had chance to catch up. I ended up blowing gearbox oil seals etc.
My advice would be to go for the manual conversion, if you want serious power, the auto box just can`t handle it
.
Regards,
Ian.