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Old 01-09-2007 | 09:12 AM
  #21  
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Default Re: Theory ... water flow

Originally Posted by bcarpman
Yep, it's all about pressure and hot spots, vapor pockets. The whole water moving through the engine too fast was a bunch of backyard mechanics making up an explaination for something they knew to be true but didn't understand.

Pressure is needed to raise the boiling point of water so you don’t get the steam/ hot spots. But if you let the coolant run through the system unrestricted there is no heat transfer. Like running over the hot coals. Run over them and it will not hurt as bad as walking. The negative point I was trying to make was the over pressure we get in boats. With out a closed system we need to regulate the max pressure.
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Old 01-09-2007 | 09:19 AM
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Default Re: Theory ... water flow

Originally Posted by insptech
Well, maybe not. Heat transfer of any kind is done when 2 molecules touch. There is no "cold transfer" just a loss of heat from one molecule to the other. Now stay with me here. If you turn on your stove burner and let it heat up, you can touch it for a very short period and not get burned(cell damage from heat transfer), why? Because enough heat didn't transfer from the burner to your skin. Now inside the engine you have water molecules pushing by some parts of the engine at a high rate of speed. If that speed is too high then there is no time for that particular spot to transfer heat to the water molecules and it will run hotter in that spot. As you slow down the flow less and less spots experience this phenomenon and the engine will run cooler. This will not show up on every engine but on some that are marginal on cooling , some restriction to flow velocity is necessary to maintain proper cooling.
Very true. Now think of all that and your Temp gauge thats reading 140......Is that a true reading of your motor temp? Nope.
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Old 01-09-2007 | 09:23 AM
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Default Re: Theory ... water flow

Thermostats at 140. Drill 3 1/8 holes in it and my water temps are steady on my 540's . I'm running crossovers with bypasses.
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Old 01-09-2007 | 10:28 AM
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Default Re: Theory ... water flow

Good topic. I understand both sides to the argument.

In our early spring/late fall cold waters, if we run without t-stats our oil temp takes forever to come up to a decent temp and backs down to a cold temp quick when throttles are let off.

During this cold water times of year, using a t-stat to bring engine water temps up we get more acceptable oil temps and duration of oil temps.

Since oil is on the other side of the metal than water, I would think that oil temp may be a good indicator of how well the water is removing heat from the engine.

I def agree that water psi as read in block should be looked at. Too low of psi may create cooling issues and of course too high of a psi may will create unwanted / unwelcomed leaks.
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Old 01-09-2007 | 11:37 AM
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Default Re: Theory ... water flow

Originally Posted by monstaaa

p.s is that a cigarette, looks like cig bilge.

Naw Stole the pic from the "show your motor" thread ...

building 496's for my 311 ....

Great info here ....m
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Old 01-09-2007 | 11:40 AM
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Default Re: Theory ... water flow

......
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Old 01-09-2007 | 12:13 PM
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Default Re: Theory ... water flow

Originally Posted by monstaaa




p.s is that a cigarette, looks like cig bilge.

Yes, it's Old School 1, an 89? Bullet.
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Old 01-09-2007 | 12:15 PM
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Default Re: Theory ... water flow

Originally Posted by monstaaa
molecule,, shmolecule





hey Ted



























just do it,,,,,,











do it,,,,,,,,,,
Nope, I like my 160 thermostats and no milky oil

Merc did a fine job on my stock 502 cooling systems
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Old 01-10-2007 | 09:42 AM
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Default Re: Theory ... water flow

Originally Posted by SB
Good topic. I understand both sides to the argument.

In our early spring/late fall cold waters, if we run without t-stats our oil temp takes forever to come up to a decent temp and backs down to a cold temp quick when throttles are let off.

During this cold water times of year, using a t-stat to bring engine water temps up we get more acceptable oil temps and duration of oil temps.

Since oil is on the other side of the metal than water, I would think that oil temp may be a good indicator of how well the water is removing heat from the engine.

I def agree that water psi as read in block should be looked at. Too low of psi may create cooling issues and of course too high of a psi may will create unwanted / unwelcomed leaks.
I run a set-up with no by-pass and no t-stat. Cold water never got motor up to temperature and I had severe condensation issues (milky oil). Installed an oil t-stat in lines between filter housing and oil cooler and problem solved. Used a simple model purchased from Summit Racing. Now oil stays free of moisture and temp gauge on motor creeps up into low range occasionally.
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Old 01-10-2007 | 10:36 AM
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Default Re: Theory ... water flow

Originally Posted by Kelly O
I run a set-up with no by-pass and no t-stat. Cold water never got motor up to temperature and I had severe condensation issues (milky oil). Installed an oil t-stat in lines between filter housing and oil cooler and problem solved. Used a simple model purchased from Summit Racing. Now oil stays free of moisture and temp gauge on motor creeps up into low range occasionally.
problem with the automotive thermostats is most I have seen run about 190* ...The word is you need 210-215 to vaporize the moisture ...which doesn't make sense .... unless with automotive water temps @ ~210 maybe moisture is not a problem ....m
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