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I'm Impressed!

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Location
Maryland
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2020 Explorer ST
#1
Hi All,
Just starting the second week with this 2020. The feature set is sick! It's got so many amenities and automation that I may have to call her Christine!
I spend a good time on the road in my business and was pleased to get a massage on the drive back tonight. The night before, I experienced the first standing punch with 93 on sport mode. For stock, it's def in the running.
Just looking for air intake and intercooler upgrade so it'll breath easier.

I do have a question though. On the last turbo car I had, it was taboo to shut the engine down after a hard pull, uphill driving or towing without letting the turbo cool down for a minute or two. Don't know if technology has changed since then but is a cool down period required with the ST? We used to put turbo timers on our turbocharged vehicles so we could walk away without fear of oil caking up on a hot turbine shaft and shorting the life of the turbo.
Thanks for your time!
 

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Location
Nevada
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2020 Ford F-150 Raptor
#2
That’s a interesting thought. After running any of our vehicles harder than normal I will usually keep them running for a couple minutes for a “cool down” period. I do not know if it is effective or not it is just an old habit like you mentioned above.
 

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Location
Texas
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2022 Ford Explorer ST
#3
Getting down to a low speed and/or low RPM for a couple minutes at the end of your drive is essentially the same thing as letting it idle. You don't necessarily have to be sitting still for the turbos to cool down.
 

OP
Suprawill1
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2020 Explorer ST
Thread Starter #4
Good to know, thx!
 

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Socal
#5
If it was the early 90's, then yes, you would need a turbo timer or let it idle for a couple of min's.

Turbo car's nowadays are liquid cooled, no need to do any of that stuff anymore.
 

OP
Suprawill1
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Maryland
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2020 Explorer ST
Thread Starter #6
Had a Supra from '95 to '07 and we had recommended timers on those. They had coolant and oil running through. I'm wondering if the turbo technology of today has improved on the coolant routing.
 

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Socal
#7
Had a Supra from '95 to '07 and we had recommended timers on those. They had coolant and oil running through. I'm wondering if the turbo technology of today has improved on the coolant routing.
It was only recommended if you were running an oil cooled turbo only on the 2JZ, for stock or similar CT12 set ups, it was not needed unless you were tracking the car.

On most/all? newer cars, the coolant keeps circulating on the turbo's after shut off. Even then, driving normal down the street for a min or 2 would be suffice to cool the turbo(s)
 

OP
Suprawill1
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2020 Explorer ST
Thread Starter #8
It was only recommended if you were running an oil cooled turbo only on the 2JZ, for stock or similar CT12 set ups, it was not needed unless you were tracking the car.

On most/all? newer cars, the coolant keeps circulating on the turbo's after shut off. Even then, driving normal down the street for a min or 2 would be suffice to cool the turbo(s)
Had a built up 7M with stock coolant cooled upgraded turbo. Ran 2.9 sec 0-60s. A modded auto helped with that. Just felt safer with a timer.

Wasn't aware the coolant kept circulating on the newer car turbos. That's good to know!
 

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#9
Oil technology is a lot better also, so coking the bearings isn't as much of an issue.
 

GearHead_1

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Exploder
#10
It was only recommended if you were running an oil cooled turbo only on the 2JZ, for stock or similar CT12 set ups, it was not needed unless you were tracking the car.

On most/all? newer cars, the coolant keeps circulating on the turbo's after shut off. Even then, driving normal down the street for a min or 2 would be suffice to cool the turbo(s)
The vehicle would have to have an electric or dedicated water pump. The Exploders/Ford Trucks do not. When the engine is off the coolant is not flowing through the turbos.

@bluesnake01, I'd love to learn how this is facilitated.
 

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#11
The vehicle would have to have an electric or dedicated water pump. The Exploders/Ford Trucks do not. When the engine is off the coolant is not flowing through the turbos.

@bluesnake01, I'd love to learn how this is facilitated.
Ecoboost engines use passive convection cooling, once the water pump is off, the coolant reverses bringing fresh cool coolant and pushing the hot turbo coolant out.

Most auto makers use a similar passive system as well on turbo car's with non electric water pumps
 

GearHead_1

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#12
Thank you, I'll read up on that.
 

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Location
Sacramento, CA, USA
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2021 Explorer ST Carbonized Gray
#13
From what I understand is turbo timers were used to keep the engine running so the oil supply is not cut off while the turbo/s were still running at high RPM. These things run at very high rpm and if you shut the engine off the is no lube for the the bushings/bearings, the timer allows them to slow down before cutting the oil supply. I'm sure cooling them down helps too, but I usually try to let my ST idle for a few minutes before shutting the engine down.
 

OP
Suprawill1
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Thread Starter #14
From what I understand is turbo timers were used to keep the engine running so the oil supply is not cut off while the turbo/s were still running at high RPM. These things run at very high rpm and if you shut the engine off the is no lube for the the bushings/bearings, the timer allows them to slow down before cutting the oil supply. I'm sure cooling them down helps too, but I usually try to let my ST idle for a few minutes before shutting the engine down.
The turbos only spin high rate when high boost demand is present. They run off of the exhaust so when the engine stops, so do they. At that point, there is no spin. They need rpm to engage but it is engine 'load' that activates them.

In my case, the turbo timer was used to let the oil and coolant cool down. If the engine were turned off directly after pulling hard enough for the turbos to engage higher boost, the heat would allow the oil to coke up on the turbo shaft causing imbalance and less freedom of rotation. It was a recipe for early turbo failure.
 

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Location
LA, California
Vehicle
2022 Explorer ST
#15
I searched top to bottom in the owners manual to find an official answers, but couldn't find any.

What I do at the start is,
  1. push to start button to wake the electronics
  2. Once the screen is all loaded, start the engine
  3. Wait it the rpm drop to the regular idle level (set seatbelt, nav, radio etc, while I wait)
  4. Drive at low rpms for the first mile or so.
At stop, I just drive slower for the last few minutes of my trip and keep the engine running on idle for 15 seconds or so and then switch off.

Edit: With the 6.xx $ per gallon now in CA, I will think twice before switching on the ST. I use my bicycle more now.
 

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#16
From what I understand is turbo timers were used to keep the engine running so the oil supply is not cut off while the turbo/s were still running at high RPM. These things run at very high rpm and if you shut the engine off the is no lube for the the bushings/bearings, the timer allows them to slow down before cutting the oil supply. I'm sure cooling them down helps too, but I usually try to let my ST idle for a few minutes before shutting the engine down.
Not how turbo's work.... As @Suprawill1 stated, they only produce boost if needed when you go WOT or close to it. The turbo may or may not spin on idle but will not produce any "boost" or run off high RPM on idle.

A turbo timer was used to move the hot oil from the turbo so they wont get cooked on the bearings as the oil itself was the only thing that was cooling the turbo as well. The coolant takes care of the now for the most part.
 

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Location
Sacramento, CA, USA
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2021 Explorer ST Carbonized Gray
#17
Not how turbo's work.... As @Suprawill1 stated, they only produce boost if needed when you go WOT or close to it. The turbo may or may not spin on idle but will not produce any "boost" or run off high RPM on idle.

A turbo timer was used to move the hot oil from the turbo so they wont get cooked on the bearings as the oil itself was the only thing that was cooling the turbo as well. The coolant takes care of the now for the most part.
All good info, thanks for sharing. That's very correct the turbo will not spin much at idle, but I was more referring to many kids I've seen racing into a parking lot with their import racers then perform a WOT snap to hear their BOV. Then shut the key off and and get out to go into store, I can't imagine the turbo stops spinning that fast so a turbo timer will help in this situation too. But either way turbo vehicles require a little more care and maintenance.
 



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