S-Type / S type R Supercharged V8 ( X200 ) 1999 - 2008 2001 - 2009
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Take the lag out of the pedal

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Old Mar 4, 2013 | 12:25 PM
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Michael Star's Avatar
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Default Take the lag out of the pedal

Is there a way to take the 1/2" or so of travel out of the pedal before it does anything? I am thinking getting the TB bored might help somewhat but it kills me that there isn't a more immediate response in the throttle.
 
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Old Mar 4, 2013 | 01:56 PM
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It's an electronic throttle, so any perceptible lag is inherent in its design; I doubt physical changes to the throttlebody like boring it out would change anything,

Maybe something is wrong with your throttle setup somewhere, I haven't driven my STR in months, but I don't recall it being particularly laggy, I definitely do recall someone taking it out for a test drive late last year when I still had it up for sale, and first application of the throttle was way too aggressive and the car unexpectedly shot forward, so if anything it might be touchy...
 
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Old Mar 4, 2013 | 02:13 PM
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Well what really triggered it for me was driving the Shelby this weekend. It has an electronic TB and the gas pedal is super sensitive (I can sneeze on it and do burnouts). The reason I was thinking boring the TB might change is due to the increase in air with less throttle input.
 
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Old Mar 4, 2013 | 02:22 PM
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Yes, while that's true, a bigger throttlebody is always more responsive (my other car has a 3.5" throttlebody on a 2.0L engine, so tel me about it), I'm wondering if yours has maybe another issue or... we need some more STR guys to chime in on their thoughts regarding throttle response at the pedal... my cars in storage for at least another month, can't really check it now to see if your observations are similar in my case...
 
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Old Mar 4, 2013 | 02:30 PM
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There's something wrong with your car then. My non-R has zero free play or lag.
 
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Old Mar 4, 2013 | 02:30 PM
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do you drive with Sport button active? thats supposed to make the throttle more responsive.

the Audi guys use a module called "sprint booster", supposed to do the same as the S button
 
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Old Mar 4, 2013 | 02:54 PM
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I drive without S (usually) and no lack of response. Had to learn how good and sensitive it is, in fact. But my last car was "only" 300HP so that's a factor maybe.

Mess with the TB and get codes, I suspect.
 
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Old Mar 4, 2013 | 03:00 PM
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Hmm, sport mode is always on and now I am wondering if it has anything to do with my random lean condition. Currently I am not under a restricted performance, but I will investigate this further.
 
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Old Mar 4, 2013 | 03:29 PM
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I think this can only be changed with a programmer that we sorely lack!!
.
.
.
 
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Old Mar 4, 2013 | 04:37 PM
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Lean? If it goes lean the PCM's got to second guess why and refuel. May even go open loop but a lag - maybe. Lean is bad...

To get a lean code it has to happen twice (separate drive cycles) in similar conditions and to be at least 25% wrong!
 
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Old Mar 4, 2013 | 05:12 PM
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Mike, the lag may also have to do with a vaccume leak and/or winter fuel in your area. I find that different fuel brands make a difference. An ECU tune minimizes lag and flat spots.
 

Last edited by bfsgross; Mar 4, 2013 at 07:06 PM.
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Old Mar 4, 2013 | 05:55 PM
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Don't tune a car with a known fault!
 
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Old Mar 4, 2013 | 07:14 PM
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Default ECU tune

Naturally, I wasn't suggesting an ECU tune to remedy a problem. This, I suggested in the event his STR is fine but he wishes to enhance its state of tune? Mike, as you're aware; as the motor's intercooler circuit heats up, the AITS signals to the ECU to pulls back timing. Perhaps this is what ails your STR? Mike, was she well heated up when you demanded performance that is normally available with cooler air intake temperatures?
 
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Old Mar 4, 2013 | 07:32 PM
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Mine has no lag. I remember the first time I test drove it I spun the tires a little on accident because it was immediately responsive and I wasn't expecting it.
 
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Old Mar 4, 2013 | 08:38 PM
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Yeah. Betting he either has a clogged fuel filter and injectors or a vaccume leak.
 

Last edited by bfsgross; Mar 4, 2013 at 08:41 PM.
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