31 replies to this topic

[tiger99]

Covering the frontal air intake on any kind of car in winter is a technique from the bad old days and supposedly achieves a faster warm-up in winter so you have demisting/defrosting quicker. You could buy internal radiator blinds, like a roller blind, with dashboard control, or a smart looking flexible external covers with flaps and press studs. (These protected the front end paintwork too, and were highly regarded by owners of things like Rover P4 and other 1950s vehicles.) Cars often did not have thermostats, and sometimes not a water pump, in those days so there was no other means of control. I have seen Minis with aluminium foil on most of the grille but never needed to do it myself, even in several very cold winters.

 

If you can get a Mini to run at -40 deg C, you may lose so much heat from the block, head, transmission case etc that you need to reduce airflow to get it up to running temperature. The oil temperature really MUST get up to a sensible value, or lots of things will work badly, and wear. Changing gears will be a misery, etc... If the water temperature remains low it is not quite so destructive. But various experts here will tell you more than I know about the evils of running too cold. My Minis usually had the opposite problem!

[Ricewind]

I had the same problem in winter with my Berkeley T60 that had a 1380 mini engine. The problem for me was excasipated by the fact that it had a more efficient shape and so used less energy (so less heat) on a motorway run. The Berkeley has a cd factor of 0.27 compared with a Mini that comes in at about 0.51. The original Berkeley was 314kg about half that of a Mini but mine was bit heavier than the original with the 1380 instead of the normal 325cc. It also has a bit smaller frontal area than a Mini.

 

One problem is the water pump, as that hardly works at all at low speed. And rather too well at high speeds (wasting energy) and the cooling requirements are less at high speed with high air flow around the engine. Then when you come to a traffic hold up after driving hard, the engine mass becomes a heat sink and then can't escape when the traffic slows down, the air flow stops and the water pump goes to sleep.

 

I shall fit an electric water pump on my latest project that can pump fast when we are stuck in traffic with little air flow and just tick over at cruising speed. Covering the frontal air intake sounds like an excellent idea seeing as in winter my old car when on a run, even the heater would go cold until I gave it some beans for a spell. There is a lot of surface area around the sump over cooling the oil which probably does not help. I can imagine a robust venetian blind thing that I can close remotely being something to consider. It could look quite cool, although my engineering is more steam punk then elegant.