1970 Triumph TR6 Mechanical Review 

It sounds like the timing is off. I would check the cam to crank timing if possible.

Sounds to me like the manifold pressure is too low at low rpm. The electronic fuel injection may not be the best performance option for the old straight six. Triple SU carburetors may be a more practical practical alternative.

Still say the oil pressure is not good - agree exhaust should have a more free flowing system

Nice car. Needs a decent exhaust. Any idea of brake horsepower?

is it hydraulic steering?