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Discussion Starter #1
Hey y'all, hope you're having a fantastic day. I got a question for you guys. Thread title might be misleading but not another way to describe it. Anyways, while having fun with my car today I sorta realized theres no power difference between about 3/4 pedal and pedal to the medal. Is this normal? Can't say I've experienced this in other cars.

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Definitely not normal.
 

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Really hard to say from here.
Maybe remove the maf coupler and see if you can tell.
Only other thing I can think is the throttle body could be bad.
 

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You should feel/hear/experience a noticeable increase around 3600-3700 RPM.

Look into your maintenance items.

Dirty air filter, bad/old spark plugs, old oil, or just some bunk 87 gas.
 

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Discussion Starter #6
You should feel/hear/experience a noticeable increase around 3600-3700 RPM.

Look into your maintenance items.

Dirty air filter, bad/old spark plugs, old oil, or just some bunk 87 gas.
I have a brand new green filter but it happened before I owned it. Car has 54k miles on engine and DCT, oil change is up to date. I definitely hear a different noise around 4k rpm. I dont feel a power difference between full throttle and 3/4 of the pedal pushed down. Butt dyno says its the same power.

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Discussion Starter #7
I have a brand new green filter but it happened before I put the green filter in it. Car has 54k miles on engine and DCT, oil change is up to date. I definitely hear a different noise around 4k rpm. I dont feel a power difference between full throttle and 3/4 of the pedal pushed down. Butt dyno says its the same power.

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my car does this some days I feel like. Mine is a 5 speed though. Some days I can floor it from 3500 rpm in second and notice it starts to pull after about 4k rpm and somedays I can floor it and its a complete turd all the way to 7k.
 

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really is kind of one of those things where you would need it on a dyno to see whats going on. Sometimes i feel like these cars want more Air then is getting sucked in
 

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Could try disconnecting battery for an hour and reconnecting to reset monitors and relearn... maybe throttle position sensor is not reading correctly
 

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Full throttle on the MK3 is 82% so doesnt surprise me if you at 3/4 throttle you dont feel a difference

My first question is how do you know the throttle is at 75% throttle ? If you has said 50% +/- I could understand your concern more

Tom
 

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Discussion Starter #12
Full throttle on the MK3 is 82% so doesnt surprise me if you at 3/4 throttle you dont feel a difference

My first question is how do you know the throttle is at 75% throttle ? If you has said 50% +/- I could understand your concern more

Tom
I don't, I was just pressing down the pedal and there was no change, thats all.

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Totally Normal, especially if you've done any mods to the intake system. The stock throttle body flows more air than what the engine can pull in, in stock form at least.

So lets say that the maximum air intake of the engine is lets say 500cfm at 6500rpm. At wide open throttle the throttle body can flow a maximum of 750cfm. At 75% throttle, the throttle body can flow a maximum of 500cfm. So in this theoretical scenario, 75% throttle is the most throttle the engine will ever need to be at it's maximum airflow, so going from 75% throttle to 100% throttle isn't ever going to do anything to engine performance. This is the case with almost all fuel injected engines, because the throttle body almost always flows more air than the engine can handle.
 

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Think about the shape of the butterfly in the throttle body. Most of the change in opening is in the initial part of the turn where it cracks open and starts to let air in. at the end of rotation there's almost no difference to the increase in flow rate as the butterfly is already mostly parralel to the flow direction
 

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The engine is also much more sensitive to low flow air than high flow air and the condition of increasing both.

The plastic zetec throttle plate actually makes up for flowing too much, the rotation if the plate was flat exposes way too much too fast and the car takes off in a jerk and leap when new and engine is tight. Too sensitive and customers complain about it. The plate shape is made to slow down the increase in flow rate to about 3X the effective rotation distance before it reveals that much opening, the slowing down makes the driveability off-idle much smoother and more progressive.
 

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Emissions... enough said....

That's what I'm thinking... That's why allot of things are not 100% Open....

Could be wrong too...
 

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i noticed on my sct gauges i can get more throttle by actually applying way more pressure to the gas pedal once already floored than needed, the throttle percentage increases. im wondering if trimming stuff down in the pedal will allow more throttle?
 

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i noticed on my sct gauges i can get more throttle by actually applying way more pressure to the gas pedal once already floored than needed, the throttle percentage increases. im wondering if trimming stuff down in the pedal will allow more throttle?
It wont help to go past 82-85%

Tom
 
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