Temp at detonation....

[1974dodgecharger]

Is it true detonation only happens at high temps? Can detonation happen if your cruising along and your temp saids 185 degrees and boom and bam detonation just suddenly happens and you blow your engine?

Or does it happened when you see that temp gauge creep up to 240 then 260 and then BAM detonation and blows up?

[Kern Dog]

There is validity to the theory. When my Charger had the detonation problems, it ran fantastic and knock free when the weather was cold or when I first started the car in warm weather.

[1974dodgecharger]

There is validity to the theory. When my Charger had the detonation problems, it ran fantastic and knock free when the weather was cold or when I first started the car in warm weather.

I was thinking this the other night...most cars I hear or saw that detonated the temps was exceedlying high and thought hmm...such as high compressin will make the temps go up, running lean can run temps up also, etc...seems it all back stems to temp as a indicator of engine detonation.

[John_Kunkel]

Diesels detonate when the engine is stone cold. Too many variables to form a general link to temperature/detonation.

[Challenger340]

We like to think of Carburetors as a "perfect" and a linear metering device...
but really,
think of what happens when Engine temps increase, as it relates to the "density" of the A/F charge delivered through the hotter Intake & Heads to the combustion chamber ?
Extremely, or OUT of stoichiometric A/F mixtures can burn erratically for a given timing advance curve.

F.I. / computer systems can "adjust" timing and fuel pulse rates in real time for air density, backup with knock sensors, etc., etc.
but,
poor old carburetors... with "static" and SET timing curves ?
well,
The hotter you get.... the leaner A/F that gets delivered through the hotter Intake/Heads, causing your timing to be OFF ! (ping-ping-ping)

You can cheat the power numbers on a Dyno the same way ? just start the run with the Head temp down around 120* TO MAKE THE CUSTOMER HAPPIER.

[1974dodgecharger]

Good info.....

[440]

My Fairlane use to ping fairly bad and lose power when the engine was heat soaked from long runs in hot weather. Cool weather not a problem.

[1974dodgecharger]

My Fairlane use to ping fairly bad and lose power when the engine was heat soaked from long runs in hot weather. Cool weather not a problem.

Good indo 440 my theory seems right....