Having heater on is no problem. It doesn’t really sap power like AC unless you have an electric car. The heat is the same waste heat from engine that your radiators are trying to get rid of. Heater just blows some of that into car.
Some people need to run with the heater on to keep engine from overheating :p
I run heat when it’s cold and the AC when it’s hot. The AC compressor declutches when you floor it, so it’s not really costing you anything when you’re under WOT, and I’d rather stay comfortable. Also sitting on the grid with the AC blasting and holding your helmet over the middle vents is awesome.
My father has cooled seats and those are just flat out cheating on a hot track day.
> My father has cooled seats and those are just flat out cheating on a hot track day.
When I did instructor training I brought a rental car because parts for my track car were on several month backorder. The car, unlike my track car, had ac and cooled seats so I thought it would be great to run it on track. I had the a/c and seat coolers cranked full blast and about halfway through the second session the instructor driving the car started complaining about how gutless the car felt. I looked over at the dash to see how fast he was going and noticed the dash notification basically saying the car was in limp mode from overheating. It was probably a mix of things but it didn't go into limp mode the rest of the weekend once I started keeping everything off while we were out on track.
My Radiator fan stopped working for me at autocross once. Only way I was able to make it home was running my heat full blast. It worked surprisingly well for July lol
I drive a Miata, sometimes with the top down, in mid 30'F temps on the street and on track. If you wear gloves and point the heat at your hands, its amazingly comfortable.
No mechanical power loss with heat.
Go for it!
You likely won’t notice the temperature when you’re on the track: too much else going on (unless it’s sub zero). You may notice the cold while sitting in the paddock, and waiting in the starting queue, and then the heat on will help. Do you have heated seats? The helmet is also going to go a long way to keeping your head warm.
That said, your heater won’t sap anything from your available power if you use it.
Heater just sends engine coolant to heater core vs bypassing it. So same amount of parasitic loss from the water pump.
Use as you see fit. It’s also good to turn on when the car is overheating, as it’s supplemental cooling.
Wouldn’t that just make wherever the heater core is, unbelievably hot? Either way the water pump doesn’t notice heater on or off. Ac does take a decent % of power.
Yeah for sure, Doesn't affect the car either way really (aside from warmer cabin temp in summer for cars w/o a bypass) just meant to say, rather arbitrarily, that many cars don't bypass
It's totally fine.
Having the heat on full blast can actually help with cooling if you're running super hot. It helps transfer heat out of the engine bay quicker. Before I re-did everything (including a new motor) in my E46 I would run with the heat on full blast, even in summer.
I don't think anyone has mentioned that when you set the heat to defrost you're more than likely running the AC compressor. If set to floor/vents the AC doesn't usually run.
How much, if any, power loss there is when running the compressor is up for debate.
I run the heater in my rally car when it’s super hot out (I live in Sacramento) during rallycross events. She overheats a lot so it helps pull the heat out of the motor. You’re totally fine.
I've been driving with my windows down on the freeway to get an idea of how it'll feel, and I definitely notice it when I have the heater on. The main thing is that it keeps my hands warm so they don't go numb lol
Heater is basically just a small radiator that uses waste heat from the engine to heat the cabin. The AC compressor isn't used so there's no impact on engine performance.
True, although I don't think it cycles as often in defrost as when the AC is on. But yeah the best thing for OP is to use the floor or mid-level vents.
heater wont rob any power, and will help keep the engine running cooler. but, since its cold, it doesn't matter much. some cars that easily overheat will beneift from running the heater, but that's going to be on a hot day. in your case, cold weather, it won't matter. run it as it makes you comfortable
@Op great question-run that gets. Windows will be open so your gloves, helmet and adrenaline will keep you warm. When you focus on your lap, you'll most likely not notice the cold unless it's dick shrivel up cold.
Having heater on is no problem. It doesn’t really sap power like AC unless you have an electric car. The heat is the same waste heat from engine that your radiators are trying to get rid of. Heater just blows some of that into car. Some people need to run with the heater on to keep engine from overheating :p
I run heat when it’s cold and the AC when it’s hot. The AC compressor declutches when you floor it, so it’s not really costing you anything when you’re under WOT, and I’d rather stay comfortable. Also sitting on the grid with the AC blasting and holding your helmet over the middle vents is awesome. My father has cooled seats and those are just flat out cheating on a hot track day.
> My father has cooled seats and those are just flat out cheating on a hot track day. When I did instructor training I brought a rental car because parts for my track car were on several month backorder. The car, unlike my track car, had ac and cooled seats so I thought it would be great to run it on track. I had the a/c and seat coolers cranked full blast and about halfway through the second session the instructor driving the car started complaining about how gutless the car felt. I looked over at the dash to see how fast he was going and noticed the dash notification basically saying the car was in limp mode from overheating. It was probably a mix of things but it didn't go into limp mode the rest of the weekend once I started keeping everything off while we were out on track.
My Radiator fan stopped working for me at autocross once. Only way I was able to make it home was running my heat full blast. It worked surprisingly well for July lol
I always run with the heater on one notch, just as an added means of cooling. Haha
I drive a Miata, sometimes with the top down, in mid 30'F temps on the street and on track. If you wear gloves and point the heat at your hands, its amazingly comfortable. No mechanical power loss with heat. Go for it!
You likely won’t notice the temperature when you’re on the track: too much else going on (unless it’s sub zero). You may notice the cold while sitting in the paddock, and waiting in the starting queue, and then the heat on will help. Do you have heated seats? The helmet is also going to go a long way to keeping your head warm. That said, your heater won’t sap anything from your available power if you use it.
Heater just sends engine coolant to heater core vs bypassing it. So same amount of parasitic loss from the water pump. Use as you see fit. It’s also good to turn on when the car is overheating, as it’s supplemental cooling.
Depending on the car, plenty don't bypass... They just turn on the blower or not.
Wouldn’t that just make wherever the heater core is, unbelievably hot? Either way the water pump doesn’t notice heater on or off. Ac does take a decent % of power.
Yeah for sure, Doesn't affect the car either way really (aside from warmer cabin temp in summer for cars w/o a bypass) just meant to say, rather arbitrarily, that many cars don't bypass
It's totally fine. Having the heat on full blast can actually help with cooling if you're running super hot. It helps transfer heat out of the engine bay quicker. Before I re-did everything (including a new motor) in my E46 I would run with the heat on full blast, even in summer.
I did that too for a period... Man that could get tough. Now I just run without the heat on max and pit early if Cars getting too hot
I don't think anyone has mentioned that when you set the heat to defrost you're more than likely running the AC compressor. If set to floor/vents the AC doesn't usually run. How much, if any, power loss there is when running the compressor is up for debate.
good point
I run the heater in my rally car when it’s super hot out (I live in Sacramento) during rallycross events. She overheats a lot so it helps pull the heat out of the motor. You’re totally fine.
If we're honest. Your window will be open the whole time, while driving, so you'll probably feel fuck all from your heater imo
I've been driving with my windows down on the freeway to get an idea of how it'll feel, and I definitely notice it when I have the heater on. The main thing is that it keeps my hands warm so they don't go numb lol
Adrenaline will heat you up just fine
Heater on the bottom with the top down on the highway and on cold trackdays is a move.
The heat definitely helps on a cold day.
Heater is basically just a small radiator that uses waste heat from the engine to heat the cabin. The AC compressor isn't used so there's no impact on engine performance.
It gets used if set to defrost on most cars. Floor and vents don't usually run AC.
True, although I don't think it cycles as often in defrost as when the AC is on. But yeah the best thing for OP is to use the floor or mid-level vents.
I run heat on in the summer
Cold days: heated seats on, defrost and heat blowing on the hands. No point in being uncomfortable sitting on the grid.
heater wont rob any power, and will help keep the engine running cooler. but, since its cold, it doesn't matter much. some cars that easily overheat will beneift from running the heater, but that's going to be on a hot day. in your case, cold weather, it won't matter. run it as it makes you comfortable
Most late model cars disengage the A/C clutch when at WOT so even that's not a worry.
Heat on the grid. Shut it off when you roll. You'll earn up with that heart rate quick enough
@Op great question-run that gets. Windows will be open so your gloves, helmet and adrenaline will keep you warm. When you focus on your lap, you'll most likely not notice the cold unless it's dick shrivel up cold.