The restauration of my 1955 F100 239 Y block is now to 99% completed. I tried to keep al original, 6V system, engine, nearly everthing. Actually I have problems with startin rotaion. The rotations are so slow that the engine do not starts. I us a new 98Ah 6V battery, new cables. First I thought the old starter is not working well, so I fixed today a new one. Unfortunately the same low rotation like the old starter does. I installed a cable from battery + to the starter, noanges.

The battery fall at starting down to 4V. So I think the new battery is bad or the secound reason could be: (and this is my question)

I reused the 272 (ECG) block and 239 (EBV) heads. Could it be, that the higher compression and the bigger pistin rings have to many turning torque? (new Pistion rings and valve springs)

Best regards
Harald