Cold spark plug, cold engine?

[Cdaniel]

I was reading on another list about one guy's claim that a colder heat range spark plug actually dropped the operating temp of his engine.

Never heard that one before. Can anyone else back up his testimony?

 

[2bav8]

Pure coincidence for your buddy.
The weather was probably 20 degrees cooler that day, lol

A colder plug mearly reduces the temp at the spark plug electrode.

It in no way will reduce the operating temperature of the motor.

 

[ratio411]

I don't know how it works, or if my experience was weird, but...
I used hotter plugs once and my engine detonated, ran hotter, then overheated. All in the first day.
The second day the car got the cooler plugs.
Dave

 

[Cdaniel]

Pure coincidence for your buddy.
The weather was probably 20 degrees cooler that day, lol

A colder plug mearly reduces the temp at the spark plug electrode.

It in no way will reduce the operating temperature of the motor.

That's what I think, but this guy claims same conditions,different temp
Who knows?

 

[Cdaniel]

I don't know how it works, or if my experience was weird, but...
I used hotter plugs once and my engine detonated, ran hotter, then overheated. All in the first day.
The second day the car got the cooler plugs.
Dave

So how much of a heat range change did you make?

 

[rbohm]

I don't know how it works, or if my experience was weird, but...
I used hotter plugs once and my engine detonated, ran hotter, then overheated. All in the first day.
The second day the car got the cooler plugs.
Dave

a hotter plug, since it runs hotter, can cause detonation. the overheating may be because you had to run the engine harder to overcome the power loss of the detonation, or your cooling system is marginal to begin with and the combination of problems caused the overheating. likely though it was a coincidence. abd 2bav8 is right, a colder plug does not reduce operating temps, just plug temps.

 

[Ozsum2]

Doesn't gas combust at the same temp? Physics folks.

 

[Cdaniel]

Doesn't gas combust at the same temp? Physics folks.

Physics, Shmisics. I'm no Physicist or a Physician even, and I didn't sleep at a Holiday Inn last night. Just a common sense gear head. And my common sense agrees with your Physics, so I'll take your word for it.

Don't grade me on spelling either

 

[ratio411]

I went up one heat range on my plugs. You are supposed to use the hottest plug you can, without detonation, for the best power.

This was the first and last time this engine had ever overheated.

I will say that I don't think it would change your engine temps. If you were to introduce physics, it would likely be opposite.
A cooler plug gets to be cooler by releasing combustion heat into the cooling system quicker, therefore it would raise coolant temps.
A hotter plug keeps heat from transfering as fast into the coolant, so your water temps would be lower if it had any effect at all.
Dave