Sans Anoraque
Read the post again I would not dare be so bold as to decide on which method was best but more to show the pro’s and con’s of each method.
I dont see how the exhaust manifold can get so cold,so quickly that it wouldn't still warm the air.
The certification standards for GA aircraft carb heat systems JAR 23.1093 require a temperature rise of 56 deg at a 60% power setting now here is the problem, nobody knows how long the carb heat will need to be applied before the ice melts, Lycoming give 30 to 120 seconds where as the CAA AIC give 15 seconds (there is now a study into this commissioned by the CAA/GASCO). But as can be seen with a power setting of less than 60 % on approach the chances of clearing the ice in time to make a difference is not possible.
With ref to a rich cut.
I recommend a little reading up on what happens in a carb with ice building up on the venturi.
Bookworm
What is the proposed mechanism for "detonation"? Other than "it says so in the POH"? It seems counter-intuitive to me. The richer mixture would seem to move further away from the detonation regime.
The detonation talked about in this instance is not mixture related it is the introduction of significantly hotter air greater than 60 deg into the cylinder head.
Hung flung dung
If you were to increase the outside air temperature at your local airport by more than 60 deg you could expect to suffer from detonation, unless you can reduce the power needed.
Bearing in mind we are talking about all aero engines here and with the lower compression engines fitted to the PA28/C150 it is a very rare event.
Shortstripper
This is quite incorrect oh is it. Read the following from Lycoming and GASCO
http://www.lycoming.textron.com/main...tionIcing.html
http://www.flyontrack.co.uk/carbice2004.htm
Detonation and its causes is a complex subject but I think you have missed the point, I am talking about detonation caused not by a change in mixture but by the extra heat put into induction system when carb heat is left to hot and full power is applied.
No I am not confusing detonation with rich cut as one you will not notice but the other will give you a major adrenalin rush. Stumble is something I do after a night out with the lads.