Could someone please tell me the CR for a USA AND Brit 1296 Spit motor.
i think they are about the same at 8.5:1, but my memory is vague here.
Also, If I said I had a 1296 Spit motor with a 1500 cylinder head shaved
down to give a combustion chamber the same depth as a 1296 head, but it only
had 120-125 lbs of compression accross all 4 cylinders, what would be your
diagnosis? I should also tell you that the rings are new, it has a sidedraught
SK and a TH2 Kent cam (about 290 degrees duration), as these will affect the
compressiuon reading. Whilst cranking to get the readings I used an
additional source of power so the battery did not run down. Also I repeated
the readings in reverse order, ie 1-4 then 4-1. The wet compresion readings
were about 165-70 lbs, but I did add about 3-4 cc of oil thereby increasing
the CR and thus the compression readings.
I'd be grateful for your interpretations.
Cheers Dennis "I just spent all Saturday taking off the cyl head and
dismantleing the front suspension on my Midget" Wilson
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