26-09-2017, 05:13 PM
The HC head overlaps part of the cylinder, so it's important that the pistons don't protrude above the top of the block at TDC, even when there is a bit of whip in a 2-bearing crankshaft. The thin gasket gives some clearance, 20 thou from memory. I suggest you check that no-one in the past has shaved the top of the block or left out the base gasket. One way to check "static" clearance is to trial-fit the head without a gasket and use small pieces of plasticine. Once you have turned the engine over by hand, the squashed material can be checked for thickness in each cylinder.
I found that less advance was appropriate after changing from the LC to the HC head, presumably because the "squish" effect causes more turbulence.
The tradeoff for more power is a slightly harsher sounding engine, especially around 2200 RPM. Things smooth out noticeably above 3000 RPM, which is my level cruising speed of about 45 in 4th gear. (1936 Pearl)
The 2-stud water branch can be fitted without a gasket if the faces are flat, Loctite SI 5660 worked well for me. I recommend 20 to 25 ft-lb as a torque figure for head nuts fitted dry (other opinions are available !).
John Cornforth
I found that less advance was appropriate after changing from the LC to the HC head, presumably because the "squish" effect causes more turbulence.
The tradeoff for more power is a slightly harsher sounding engine, especially around 2200 RPM. Things smooth out noticeably above 3000 RPM, which is my level cruising speed of about 45 in 4th gear. (1936 Pearl)
The 2-stud water branch can be fitted without a gasket if the faces are flat, Loctite SI 5660 worked well for me. I recommend 20 to 25 ft-lb as a torque figure for head nuts fitted dry (other opinions are available !).
John Cornforth