first start break in
I was going to use distilled water instead of antifreeze because I believe it cools better?
I have never seen any real evidence of that, but I suppose if the minerals are taken out it could make a difference.
Personally, I would do the stat mod and get the biggest 110 volt fan I coud find in front of the radiator during the break in.
On the stat subject, I have seen and worked on a lot of cars that got hot spots from air in the block and push the water out faster than you can try to get in there before the thermostat ends up opening.
Then when it finally opens the new coolant gets blasted back out from contacting those hot spots. (I know people that have been burned pretty bad from this.)
Even if that doesn't happen you still have to wait for the stat to open to be sure the system is actually full and the air bubbles are out of it.
With the 1/8 hole in the stat housing this NEVER happens as the air gets circulated out as soon as the engine starts and before the stat ever opens. (hot spots never get the chance to form)
This way, you put coolant in it till it's close to full and start the engine.
As soon as the engine is running you can top it off and put the cap on.
That's it.
It makes things WAY easier and faster even if you are just changing a hose or something later on.
I can only imagine a lot of people don't understand what the advantage to the hole is, or everyone would do it when they put a stat in.
Then there's the question "If it works so well and such a good thing, then why are they not made this way in the first place?"
Well, some are. :D
Some have a hole with a little brass or whatever pin in it that fits loosly, and they call them jiggle valves.
I have even seen the same hole with a cotter pin in it with the legs of the pin flared so it stays there.
Where this picture says the air valve must be up, is because this thermostat sits upright instead of laying down flat like ours do.