Originally Posted by
PeeBee
Thanks Mark. I just did a quick measure up of the Tridon unit I have that fits the chev - it runs 2 of these, and the actual vent valve is only 14mm dia. Doing the numbers, with two thermostats open, the combined orifice is 308mm2. the TD is 630mm2. Something does not look right. The area i am looking at is the copper plunger to its seat - is that correct? I am currently running the 182 degF units, but have 160DegF units in hand to try some time down the track. If I looked at this by proportion, engine size V orifice, the chev needs something like 975mm2 combined, which equates to an orifice opening of roughly 25mm x 2 thermostats. Is this right ?