I feel dumb asking this question, but here goes...

Riot_Polizei

Comp Engineering Student
:
2002 Mazda Protege5
One of my coworkers says some very outlandish "car performance facts" that I've doubted heavily. If I ever provide a counterpoint, he always says the same annoying s***. "Well dude, I've been racing for years and that's what worked for me"...argh. He's never proven that he ever raced to begin with.

Today, he told me that to "redirect heat from the engine" and to increase performance when driving hard, you must turn the heater all the way on full blast.

It sounded ridiculous, but I guess I got to get a second opinion on this. Is it true?

From what I understand, the combustion cycle causes loads of heat, which is marginally mitigated by the exhaust system (hot byproduct escapes the system). Yet, since the block and surrounding metal parts absorb a lot of that heat, a circulating coolant system is needed to reach some lower thermal equilibrium between the engine and the coolant mixture. The coolant absorbs the heat, simple. Once the coolant is hot enough, it opens the thermostat, releasing the hot liquid into the radiator. The radiator fan switches on, liquid rushes into the radiator, disperses downward, and gets cooled by the incoming air/fan blowing against the fins. From there, the "cold" coolant is flushed back to the engine to maintain a lower temperature, thus repeating the cycle.

Now, about the heater...

The heater core is a mini-radiator that this hot air can pass through. If you turn on the heater, then some valve opens up, allowing the flow of hot gasses into the cabin of the car.

Theoretically, this would divvy up the exhausting of the hot coolant, right? But I feel like I'm missing something. The cooling/heating system is very closely intertwined, and is driven by that water pump as well. If the water pump must work harder to heat the car's interior while cooling the engine, then wouldn't that technically impart more energy into the given system and tax the engine more?

Well? What do you guys know that could help my understanding (and perhaps give my coworker some hard evidence so that he shuts his gob for once)?
 
I'm gonna throw it out there and say that anything helps lol That being said, it probably isn't marginal enough to justify roasting yourself. I remember when my head gasket blew and I was leaking coolant pretty badly at the water pump. I had to stop very 20 k or so to fill it, but had the heat cranked to try and keep things as cool as I could. I remember holding my hand on the heater vent and it would get hotter and hotter until it was almost literally burning my hands, and I sort of used that as the indicator for it needing some water lol . Anyway! can't say if it really helped, but anyone driving hard enough to actually make use of this would probably already have the heater core removed and the car gutted. So it's sort of irrelevant.

Your co-worker sounds like a no-mind, regardless of whether or not he's right lmao
 
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Back in the 90's while driving into Death Valley (on vacation and in a rental car) I used this trick (heater temp wide open and fan speed full blast) to keep the engine from overheating. It works, as the heater core acts like a small secondary radiator (or heat exchanger), but it's uncomfortable as can be! To use this as a performance enhancing method seems silly to me. Depending on the water pump, assuming it's belt driven and going around anyway, I don't think any extra load from more water flowing will be significant, but that's just an somewhat educated guess.

Good luck with your coworker. Been there, seen that, glad I'm retired! Lol
 
Back in the 90's while driving into Death Valley (on vacation and in a rental car) I used this trick (heater temp wide open and fan speed full blast) to keep the engine from overheating. It works, as the heater core acts like a small secondary radiator (or heat exchanger), but it's uncomfortable as can be! To use this as a performance enhancing method seems silly to me. Depending on the water pump, assuming it's belt driven and going around anyway, I don't think any extra load from more water flowing will be significant, but that's just an somewhat educated guess.

Good luck with your coworker. Been there, seen that, glad I'm retired! Lol

Thanks for the response! I knew there was a reason why I didn't outright tell him he was full of s***...I went through a few calc-based physics classes, and I retained a bit of thermo tips and pointers. He only marginally made sense, but I guess there is a bit of truth to it.
 
Cranking the heater up would, theoretically, assist in dealing with excess engine heat. However, it creates the problem of overheating the passenger compartment. "Ha!" you say. "I'll just roll down the windows." But that will screw up the aerodynamics and put more load on the engine. Best to keep the windows up.

Also, there would only be a benefit (marginal though it would be), if the radiator wasn't capable of removing the excess heat and the engine were, thus, getting too hot. As it is, I strongly suspect that the radiator has more than enough capacity to dissipate all the excess heat created by the engine.
 
On a mass produced passenger car that was sold worldwide??? Not a chance in hell it would make a faintest difference to it's "performance". Diddly squat!!

I have seen WRC (World Rally Championship) cars do this but only when the car was overheating, and that was as a last resort to try bring the temperature down. But to try that on a passenger car in hope of gaining performance is comical to say the least.


I think your co-worker's brain has overheated from having his heater on full tilt chasing a "performance" advantage. (rlaugh)
 
One of my coworkers says some very outlandish "car performance facts" that I've doubted heavily. If I ever provide a counterpoint, he always says the same annoying s***. "Well dude, I've been racing for years and that's what worked for me"...argh. He's never proven that he ever raced to begin with.
You work with GJ-Molester?
 
bwahahaha @ Buzzman

I had a car twith a bad radiator once and yea, running the heat at full blast kept it cooler longer.
But perfomance? No
 
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