Improving the cooling on our TJs

Can somebody explain or post a picture of where a hole should be drilled in a thermostat? Also I have seen the size mentioned as being 1/16 or 1/8, which is best?

Drill it right beside the jiggler. 1/8" is fine, don't overthink it, you're just helping it bleed air out easier.
 
Thanks, but what is the jiggler?
should the hole be in the flat rim close to the inner opening?
 
Can somebody explain or post a picture of where a hole should be drilled in a thermostat? Also I have seen the size mentioned as being 1/16 or 1/8, which is best?

Doesn’t matter. I never drilled mine, but I do burp the system …
 
Many thermostats already have a air bleed hole in them. I attached a picture of one, this would be where to drill a small hole 1/8” would work. I have found that filling the cooling system my Jeep with the heater hose disconnected at the heater core then reconnecting it when coolant comes out. (Don’t forget to tighten clamp) then I run the vehicle until it gets hot shut it off until it cools then refill.. this works well for getting all the air out of the system.

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How is an Edelbrock head supposed to help with cooling? And lol @ a 50hp gain.

Simple, it is called math, physics and efficient design. See in the modern world we understand that aluminum is a better heat conductor than a chunk of cast iron, that bigger and better designed intake and exhaust ports/valves flow more air, that combustion chamber design equal more horsepower/mpg, that aluminum is lighter than cast iron.

The Jeep 4.0L cast iron head is a relic of the past, it traps heat and sends it to the radiator for rejection, heat that the Edelbrock head sends down the exhaust or radiates or convects from the surface of the head. The Edelbrock head more efficient combustion chamber designs allows higher compression and better fuel burn which equals more power and better mileage.

The Edelbrock head is the cheapest way to more power and better efficiency for your 4.0L.

Don't be that old dog that can't learn new tricks.
 
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Simple, it is called math, physics and efficient design. See in the modern world we understand that aluminum is a better heat conductor than a chunk of cast iron, that bigger and better designed intake and exhaust ports/valves flow more air, that combustion chamber design equal more horsepower/mpg, that aluminum is lighter than cast iron.

The Jeep 4.0L cast iron head is a relic of the past, it traps heat and sends it to the radiator for rejection, heat that the Edelbrock head sends down the exhaust or radiates or convects from the surface of the head. The Edelbrock head more efficient combustion chamber designs allows higher compression and better fuel burn which equals more power and better mileage.

The Edelbrock head is the cheapest way to more power and better efficiency for your 4.0L.

Don't be that old dog that can't learn new tricks.

You have no idea what you are talking about and no understanding of the concepts you think you do.
 
Simple, it is called math, physics and efficient design. See in the modern world we understand that aluminum is a better heat conductor than a chunk of cast iron, that bigger and better designed intake and exhaust ports/valves flow more air, that combustion chamber design equal more horsepower/mpg, that aluminum is lighter than cast iron.

The Jeep 4.0L cast iron head is a relic of the past, it traps heat and sends it to the radiator for rejection, heat that the Edelbrock head sends down the exhaust or radiates or convects from the surface of the head. The Edelbrock head more efficient combustion chamber designs allows higher compression and better fuel burn which equals more power and better mileage.

The Edelbrock head is the cheapest way to more power and better efficiency for your 4.0L.
Your claim that simply installing an Edelbrock head would give a 50 HP boost or significantly better cooling is pure bullshit.
 
Your claim that simply installing an Edelbrock head would give a 50 HP boost or significantly better cooling is pure bullshit.

So Jerry prove me wrong, give me the math and science behind your claim.
 
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I understand that I am just a stupid old guy with an advance degree in automative engineering. Thanks for exposing my ignorance.

You're welcome.

Since you have an advanced degree in automotive engineering, hopefully a little hint will allow you to get yourself pointed down the right path without me having to break shit down Barney style for you. Consider an engine and associated cooling system vs combustion chamber/exhaust gas temps in relation to an aluminum head vs an iron head. Go ahead. I'll wait. That is of course just aimed at your comments on cooling. The HP comments are just laughable but we can do that too later if you want.
 
So Jerry prove me wrong, give me the math and science behind your claim.
LOL it's the other way around. We know what you're claiming is bullshit, no head is going to give 50 HP by itself. And an aluminum head, while aluminum does conduct heat better, is not going to make a significant effect on the engine's running temperature.
 
Overall engine/cylinder head design but mostly I'm going with that small detail of turbo vs n/a 😂

Simply saying technology marches on, the Edelbrook head is an advancement in technology that can offer TJ owners path to more hp and efficiency.
 
Simply saying technology marches on, the Edelbrook head is an advancement in technology that can offer TJ owners path to more hp and efficiency.
Yes it does but your claim of 50 HP by changing to an Edelbrock head is pure bullshit. Same with your claim of it cooling better. YES aluminum transfers heat more readily than cast iron does but simply going with an aluminum head is not going to make a significant improvement to cooling on the 4.0 engine.
 
LOL it's the other way around. We know what you're claiming is bullshit, no head is going to give 50 HP by itself. And an aluminum head, while aluminum does conduct heat better, is not going to make a significant effect on the engine's running temperature.

While here you go Jerry,
. Who would not like 66hp and 66ft torque.