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Partial throttle feels faster than full throttle

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Based

Senior Member
Messages
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84
Location
Nope
#1
Idk if this is tune related or if this is common among many cars but it feels like my car is slower if I punch it rather than gradually increase throttle input.

Say I'm in second gear at 3k rpm. If I gun it it does move but it doesn't push me back nearly as much as if I just gradually press the throttle. Maybe it is a traction issue? I remember feeling this way with my previous car as well but that one was naturally aspirated.
 


Messages
165
Likes
42
#2
Your car's brain is trying to save your engine. If you dump tons fuel into your engine, combined with a low volume of air, at a relatively low rpm, it will bog.

This has to do with mainly with timing. If you try to burn 180hp's worth of fuel, while your engine is only in the 125hp portion of the powerband, you will get an extremely lean mixture, due to lack of oxygen, which will cause very high cylinder pressure. This can damage your pistons, rods, bearings, ...etc. To prevent this, your ECM will adjust your timing to ignite your fuel at a later point of the pistons combustion cycle. This results in a very low pressure combustion, lots of wasted energy, in the form of unburnt fuel, and thus a lack of power.
 


Messages
247
Likes
172
Location
Richmond
#3
There is actually some truth to the car feeling faster at part throttle. When you have a smaller throttle opening you have a higher air velocity in the manifold which in turn increases torque. You are also spooling the turbo behind the throttle plate so that when you do open it up fully you have a prespooled turbo that will react very quickly to build boost pressure in the manifold.
 




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