Coolent system upgrade questions

[amalventano at sc.rr.com (Allyn)]

> like 10-15%. then try and see how cool it runs.
> Al

>  Why do that?  Corosion (SP?) will go through the roof> Just a quick two 
> cents from the Okie Gallery...
> David

ok, heres the deal. i always run no more than 20% glycol. it is sufficient 
to minimize corrosion. generally speaking, more than 20% ends up doing more 
to prevent freezing, and ends up lowering the heat capacity of the coolant, 
resulting in the high temps everyone sees. here is what ends up happening:

- 20/80 mix: enough glycol to deter corrosion and lubricate the water pump 
seals. you get as close as possible to heat capacity of water, keeping 
coolant system efficiency as high as possible.

- 50/50 mix: corrosion may be better prevented by the higher glycol content, 
but this ends up being far outweighed by the _way_ higher local surface 
temps in the head and block (higher temps = more corrosion, no matter how 
much glycol you throw at it). the higher coolant temp results in higher 
coolant pressure, which causes lower life of coolant hoses. this also 
ultimately ends up raising under hood temps, reducing the life of engine bay 
wiring, while embrytiling all harness connector plastic parts.

i've seen this happen first hand, learning the hard way on my first couple 
of roccos.

i see your $0.02 and raise you $0.04

Al