As the one who raised the spector of doghouse shroud with single port tins, it's good to hear that people have been running this combination for long spells without issue. I have no expectation that it is a problem, but I only brought it up to Colin as a possibility because:Bartoli wrote:I have pretty much the identical setup, single port heads, doghouse cooling system, stock single vacuum distributor, stock muffle, and a Brosol H30/31 carb on a 1600cc engine. I also have dished pistons that lower my compression ratio a bit.
1) It's an observable delta from the stock setup on his engine, and therefore something to be considered.
2) Both Bob Hoover and Jake Raby spent inordinate amounts of time and effort to suss out the stock cooling system with different sorts of instrumentation. Both were greatly surprised at what they learned, as the results flew in the face of their respective intuitions. Something that can surprise both those guys is something to think twice about.
Bartoli wrote: I don't have any gauges; I did have a Berg temperature dipstick at one time. I never did see it light. When the ambient temperature is in the 60s and 70s, the dipstick stays cool to the touch all the time. 80s, pretty hot, you could pull it out, but don't hold it for long. 90s, you can't really even hold it in your hand.
It's been fairly well-established that CHT and oil temperatures are independent of one another. CHT varies rapidly with load. Oil temperature varies more slowly and is more affected by ambient temperature.
Personally, I really don't like the ring-under-the-spark-plug sensor. In the first place, the ring used is usually a broached-out electrical stud-mount connector. It is a pathetic replacement for the spark plug gasket, which is a carefully engineered integral component of the spark plug itself. Add in the fact that the same ring connector is likely to be retained with each spark plug change, and you're just asking for combustion leaks.
In the second place, I'm of the opinion that the ring-under-the-spark-plug sensor is simply reporting the temperature of the spark plug, more than the head itself.
Have you read this?Bartoli wrote:I've also noticed the distributor body gets very hot on warm/hot days.