Engine Masters

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Wild one

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Watched an episode of Engine Masters tonight that makes you go hmmm.They were comparing aluminium to cast heads,but the thing that really got my attention was the power output in relation to oil temps.They ran oil temps of 182 and 210,and found both 6.5 hp and torque differances on the cast iron heads,and almost 13 horsepower and torque differances with the aluminium heads.I'm kind of curious which oil temp you guys think created the better power levels.
 

Sillygoose

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love that show, wish i had more time to dabble with that stuff
 
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Wild one

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I was surprised at how much more power they got with the aluminium heads when the oil temps were at 182 compared to 210. I've always been a fan of oil temps under 200F,as the film strength starts to degrade fast above those temps,but the gain in power surprised me.With the dual filters on my truck,i have to really be beating on it,to get the oil temps above 195.I do know both the wifes car and my truck are noticably quicker at the track if the coolant and oil temps are both under 170,but i always attributed it to the cooler intake and combustion temps,but now i'm wondering if it might also have something to do with the oil temps.I'm guessing the cooler oil contributes to better ring seal,which will contain more combustion pressure in the combustion chamber,and therefore make more power.But that's only my theory,i have nothing to back it up,but there's not much more that i can see as to why the cooler oil temps made more power
 

Burn2k12Ram

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I was surprised at how much more power they got with the aluminium heads when the oil temps were at 182 compared to 210. I've always been a fan of oil temps under 200F,as the film strength starts to degrade fast above those temps,but the gain in power surprised me.With the dual filters on my truck,i have to really be beating on it,to get the oil temps above 195.I do know both the wifes car and my truck are noticably quicker at the track if the coolant and oil temps are both under 170,but i always attributed it to the cooler intake and combustion temps,but now i'm wondering if it might also have something to do with the oil temps.I'm guessing the cooler oil contributes to better ring seal,which will contain more combustion pressure in the combustion chamber,and therefore make more power.But that's only my theory,i have nothing to back it up,but there's not much more that i can see as to why the cooler oil temps made more power
I bet your right and both help.
 

Ludville1

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Saw that episode a while back. Was also surprised at the power increase, as well as the significant weight savings over the cast iron heads.
 
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Wild one

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Saw that episode a while back. Was also surprised at the power increase, as well as the significant weight savings over the cast iron heads.
That was a smallblock to,the weight savings on big block heads is even more noticiable,lol. If i remember right when i put aluminium heads on my old big block Camaro, the weight savings were over 50lbs a head. Pulling the aluminium heads was a lot easier,lol
 

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Oil temperature is more indicative of engine temperature. People refer to coolant temps as the primary indicator, but there isn't any coolant flowing around the lower end of the block. If the oil is hot, you can almost guarantee the engine as a whole is hot regardless of what the coolant temp says. Hotter engine = tighter engine.
 
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Wild one

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Oil temperature is more indicative of engine temperature. People refer to coolant temps as the primary indicator, but there isn't any coolant flowing around the lower end of the block. If the oil is hot, you can almost guarantee the engine as a whole is hot regardless of what the coolant temp says. Hotter engine = tighter engine.
That's a given,but theoritically a tighter engine should make more power. The hotter the engine runs the tighter it's clearances are going to be,and tighter clearances are going to generate more friction.
 

Scottly

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That's a given,but theoritically a tighter engine should make more power. The hotter the engine runs the tighter it's clearances are going to be,and tighter clearances are going to generate more friction.
Ask NASCAR about tight engines...When the rules allowed it, they built loosey goosey ones to qualify with, because they produced more power.
 

HEMIMANN

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210F, without looking at the other posts.

Thermodynamics states the higher the temp, the higher the pressure or PV = nRT, for same cylinder volumes V being constant, n already being a constant, and the same type of induction R being constant, then P = T. They both go up and down in tandem.

Cooling induction air compared to non-cooled induction are different induction systems - the air mass 'R' is different. So the goal is to induct cool air into a hot engine - this is the definition of a turbocharged, aftercooled, high compression diesel engine. The hotter they run the more power and less fuel they are.

This is why cooling the combustion via EGR hurts power and fuel economy - just to get a single exhaust pollutant lower (NOx). This happened with EPA Tier 3 diesel engine regulations - we got nothing but complaints. R*tarded injection timing and added EGR to cool peak flame temps, required more fuel to make same power and sooted oil badly.

Tier 4 final decided to advance timing back, and get rid of NOx in exhaust via the SCR chemical factory. What a kluge!
 
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Wild one

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210F, without looking at the other posts.

Thermodynamics states the higher the temp, the higher the pressure or PV = nRT, for same cylinder volumes V being constant, n already being a constant, and the same type of induction R being constant, then P = T. They both go up and down in tandem.

Cooling induction air compared to non-cooled induction are different induction systems - the air mass 'R' is different. So the goal is to induct cool air into a hot engine - this is the definition of a turbocharged, aftercooled, high compression diesel engine. The hotter they run the more power and less fuel they are.

This is why cooling the combustion via EGR hurts power and fuel economy - just to get a single exhaust pollutant lower (NOx). This happened with EPA Tier 3 diesel engine regulations - we got nothing but complaints. R*tarded injection timing and added EGR to cool peak flame temps, required more fuel to make same power and sooted oil badly.

Tier 4 final decided to advance timing back, and get rid of NOx in exhaust via the SCR chemical factory. What a kluge!
My Dad was into tractor pulling back in the 70's,and he used to adjust the pump timing constantly on the John Deeres depending on track conditions.Kind of miss those days,lol
 

HEMIMANN

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My Dad was into tractor pulling back in the 70's,and he used to adjust the pump timing constantly on the John Deeres depending on track conditions.Kind of miss those days,lol

Yep - tuning by screwdriver was the bomb.

When we rolled out the 1st Cummins all-electronic engines, it was no longer intuitive pushing buttons on a laptop what the engine would respond to. It was spooky. Still is, for me. Analogue control had benefits, too.
 
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