Quote:
Originally Posted by chrisgerman1983
You are correct that that would be a better analogy. And yes it would also work very well... people put plastic over their windows all the time, wich turns the air space into an insulator. Most people would be extatic if their home could retain an additional 10 degrees for a 4 hour period.
|
Another error.
An assumption that 10 degrees more than standard is being maintained for any length of time is just that.
A single anecdotal report of "hood felt warmer" doesn't qualify.
I would also argue against the validity of any type of insulation on a typical hood creating a 10 degree difference in any measurable engine parameter.
You can stuff the entire engine bay full of cardboard or bubble foil and you'll only get 10 degrees difference when it eventually ignites.
To your analogy....
The plastic is to reduce drafting from leaky window glazing, frames, and installation framing. The air space created between the plastic and window, if any has little R value, anywhere from R 0 to R 3, and due to its purpose of blocking drafts, the R value as far as the homes enclosure is basically nil as it is outside that enclosure.
Must be careful in comparisons.