We always block them off & fit a hose from the heater outlet on the back of the head & take that to the top tank of the rad,,, yeah it takes a few more mins to warm up (barely any difference) , but the benefits of
more equal heat distribution across the length of the head & also
much better cooling solution for those very hot days stuck in traffic, makes it all more worth while than just about any other cooling mod in a mini.
like Doc said you can take it through your heater if you like ...but i "Never"--->Repeat "NEVER" ever take it back to the bottom hose... total waste of time pushing hot water back into the hot engine in my books....
& before anyone jumps on me attempting to suggest that it gets cooled through the heater,,, ---> yeah """A BIT""" --->
it doesn`t get very cooled at all, try a Pyrometer (infra red temp sensor thing-a-me-bob) on your heater return hose when you`re stuck in traffic on a 33deg heat day & remember that all that hot water that "
Isn`t" getting very cooled from the heater is going back into your bottom hose & straight back into an allready hot donk,,, Nice hey??? (NOT)
a small fitting (piece of copper pipe) soldered into the top tank of your rad costs almost nothing to do while you have your rad out getting squewered/cleaned/re-cored & is worth it`s 100 times it`s weight in gold for doing it.
& i always run a thermostat,,, i believe that the only reason that people took them out & made a blanking sleave was
originally to save having the thermostat give trouble sticking shut, or sticking open while racing,,, Nothing to do with creating a constant temp (originally)
however people seemed to have decided (these days) to believe that it`s a more of a constant temp thing & not the reliabiltiy while racing thing
ok,,, i`m done

class dismissed for the day, it`s beer-o-clock
