What not to do in a turbo charged car
Aug 24, 2017, 02:32 PM
#7
I went to the Youtube page for this video, there was one very interesting comment -
- I'm not an engineer. But I am a professional driver. If you floor the accelerator pedal at low RPM in a manual vehicle, nothing immediately happens to the boost, neither will it damage the engine. The accelerator will open the butterfly in the throttle body to allow more air, the computer will measure how much air is being forced into the engine per stroke and inject the required amount of fuel to achieve a clean burn as predetermined by the ECUs' fuel-air mixture mapping. This results in increased engine speed which correlates to increased exhaust gas flow which in turn increases the rpm of the turbo which THEN increases the boost pressure incrementally as the engine gains speed until peak boost is reached and the wastegate is actuated. What you're referring to is called laboring the engine, which is only 'undesirable' as it won't actually damage anything other than the drivers' pride if they don't compensate for the lack of power at low RPM in a high load scenario and actually stall the vehicle. The most common high load scenarios encountered would be driving on an incline, or attempting to overtake without downshifting. The same applies to N/A vehicles as well. This would be better classified as one of your pet hates, not an actual 'do not do'. (you may be referring to the thermodynamic efficiency of a gasoline engine and its relativity to combustion efficiency in a high load scenario, which is something completely different and has more to do with fuel efficiency than any damage that might occur)
What do you guys think? Is lugging the engine possibly damaging or is it just a dumb thing to do?
- I'm not an engineer. But I am a professional driver. If you floor the accelerator pedal at low RPM in a manual vehicle, nothing immediately happens to the boost, neither will it damage the engine. The accelerator will open the butterfly in the throttle body to allow more air, the computer will measure how much air is being forced into the engine per stroke and inject the required amount of fuel to achieve a clean burn as predetermined by the ECUs' fuel-air mixture mapping. This results in increased engine speed which correlates to increased exhaust gas flow which in turn increases the rpm of the turbo which THEN increases the boost pressure incrementally as the engine gains speed until peak boost is reached and the wastegate is actuated. What you're referring to is called laboring the engine, which is only 'undesirable' as it won't actually damage anything other than the drivers' pride if they don't compensate for the lack of power at low RPM in a high load scenario and actually stall the vehicle. The most common high load scenarios encountered would be driving on an incline, or attempting to overtake without downshifting. The same applies to N/A vehicles as well. This would be better classified as one of your pet hates, not an actual 'do not do'. (you may be referring to the thermodynamic efficiency of a gasoline engine and its relativity to combustion efficiency in a high load scenario, which is something completely different and has more to do with fuel efficiency than any damage that might occur)
What do you guys think? Is lugging the engine possibly damaging or is it just a dumb thing to do?
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Aug 24, 2017, 02:38 PM
#8
IMO, if the car was tuned properly, you should be able to perform any level of throttle position at any RPM and have no adverse effects. Lugging the engine should only result in low power and not damage. I have heard of people blowing their motors when flooring it in 5th during boost due to high as hell load, but a good tune should make that safe too.
Aug 24, 2017, 02:54 PM
#10
Evolved Member
Aug 24, 2017, 03:23 PM
#12
EvoM Guru
iTrader: (1)
The only issue would be possibly causing compressor surge. Properly tuned, no harm will come to the engine.
Aug 24, 2017, 04:37 PM
#13
Evolved Member
My car has plenty of power to pass on 2-lane highway in 5th so I only down shift if traffic is slow. I think engines that pop doing this are stock blocks being pushed to their limits. The other day the how much power can a stock block take question was asked and one of the answers given was 600 hp.
Aug 25, 2017, 05:06 AM
#14
its directly relevant here. The Evo engines are homologated for Rally. And i tell you why its important here.
All AWD Turbo engines needs to be restricted for rally. There for the engines run between about 3000- 5800rpm usually during rally. Below and above that we loosing power like crazy. So your sweet spot is about 3300- 5600rpm.
Since its a very small power gap, we try to over shift to solve this problem, and use TQ only as a power. (which basically we have a lots of TQ but very small HP)
Countless times you do accelarete out fo turns with a "wrong " gear and let the TQ work for you. So it is very common a 3-4 gear acc. from around 3000 RPM. Not uncommon the same with 5th gear.
So around 3000 rpm and above the full acceleration in the given gear shouldn't be a problem for the engine. Below that .... i never tried.
All AWD Turbo engines needs to be restricted for rally. There for the engines run between about 3000- 5800rpm usually during rally. Below and above that we loosing power like crazy. So your sweet spot is about 3300- 5600rpm.
Since its a very small power gap, we try to over shift to solve this problem, and use TQ only as a power. (which basically we have a lots of TQ but very small HP)
Countless times you do accelarete out fo turns with a "wrong " gear and let the TQ work for you. So it is very common a 3-4 gear acc. from around 3000 RPM. Not uncommon the same with 5th gear.
So around 3000 rpm and above the full acceleration in the given gear shouldn't be a problem for the engine. Below that .... i never tried.