Gas pedal mod or jms pedalmax

spiller said:

Norm, I don't quite get your stance on this unit. Are you for or against?

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I was commenting on why the reviews are so strongly positive, nothing more. It's up to individual readers to decide how strongly they think the review score might be skewed "in favor of".


But personally, I don't want an "aggressive" throttle opening rate. Especially anything that would show up in the 25% and smaller range of throttle %. At any speed, whether that be 100 mph through T12 at NJMP/Thunderbolt or 15 mph through the intersections in my neighborhood, I'm going to be going through the corners with my right foot at least lightly on the throttle. Not on the brake pedal in the corner at all unless traffic ahead makes braking there unavoidable.


Norm

Norm Peterson said:

I was commenting on why the reviews are so strongly positive, nothing more. It's up to individual readers to decide how strongly they think the review score might be skewed "in favor of".


But personally, I don't want an "aggressive" throttle opening rate. Especially anything that would show up in the 25% and smaller range of throttle %. At any speed, whether that be 100 mph through T12 at NJMP/Thunderbolt or 15 mph through the intersections in my neighborhood, I'm going to be going through the corners with my right foot at least lightly on the throttle. Not on the brake pedal in the corner at all unless traffic ahead makes braking there unavoidable.


Norm

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I see what you are getting at (which was my first thought when reading your last post). As you say, it's probably a personal thing. I learnt lots about throttle control, when to be on it, how much to be on it and when not to lift off it while tracking my GT3 which had an incredibly sensitive throttle. I would say it definitely improved my ability to control the throttle more effectively in a variety of situations because it required such attention to input. Granted, that was a tuned car. I haven't yet fitted the pedal max but will report back once I've tried it out.

Yes me too on the warranty issue, but plain and simple here. .It's a performance item. My Gt launches way better from a stop now. Has to be faster than it was. It was wasting time deciding how fast I could get up to speed. Go ahead and mash your non-enhanced throttles to the floor faster. It wont open faster than mine. I also doubt the premium model sport function is opening your throttle quicker. I have to admit if I wasnt such a tightass for the most part I'd have bought the pedalmax a few years ago. ..now on to the pedal play mod.

hiccup said:

Yes me too on the warranty issue, but plain and simple here. .It's a performance item. My Gt launches way better from a stop now. Has to be faster than it was. It was wasting time deciding how fast I could get up to speed. Go ahead and mash your non-enhanced throttles to the floor faster. It wont open faster than mine. I also doubt the premium model sport function is opening your throttle quicker. I have to admit if I wasnt such a tightass for the most part I'd have bought the pedalmax a few years ago. ..now on to the pedal play mod.

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LOL, it will open at identical rates. The signal to open the throttle body doesn't reach the throttle body any faster. You just don't get it.

Your car doesn't launch any better than any stock GT. In all actuality, you lose the ability to modulate the pedal. When you're trying to modulate traction with your foot, less makes it more difficult. What you feel is all in your head. It feels faster because you have less modulation.

As for the premium sport and track mode, they absolutely alter throttle mapping. They however (like the pedalmax) won't open the throttle body any faster, as that is the result of the input required from your foot.

I'm pretty sure that the throttle opening rates at under 25% throttle are "speeded up" relative to the OE rates somehow.

Stepper motors do have an upper limit to how fast they can 'move', what we don't know for the purposes of this thread is what that limit might be, how much slower than that the OE opening rates are, and why they're slower.

Nor does there seem to be any hard data available indicating how much actual improvement in measured performance stats actually happens. Shouldn't be too hard for somebody to set up an A - B - A test sequence . . .


Like spiller, I do have some experience-based grasp of how a more sensitive throttle demands more of a driver under conditions where you want (need) it to be easy to get a certain amount of throttle without unexpectedly getting any more than that. Just that my experience is with a mechanically-operated throttle, or more in line with what Chef jpd and K-roll 302 have dealt with (but with my mechanical fix intentionally slowing the early opening rates down).


Norm

Livernois also has a throttle booster device, I wonder if we reached out to them if they could comment on what the effect actually is with these? They offer both tunes and a booster, so they see value in it as well.

I did a little data logging on Pedalmax and as far as I can tell 0 to wot was not faster but at any given pedal position the TB was open about 60% more. That was fine for me daily driving. With my foot calibrated to our 4 other vehicles it's always fun to get in the ecoboost and have a lot more power at the same pedal input as my other cars. Just disappointing when I'm at 3/4 and press it full and no more go. Otherwise I need to consciously think about just pushing it farther but for me it's nice to have the power more effortlessly. I'm pretty sure if I did a track day I would remove it though.

Guys its just throttle expo. it makes pedal input vs throttle output from linear or what sounds like in the factory tune less than 1 to 1; to non linear, more than 1 value output for 1 value input.

The throttle becomes touchy and ramps up faster.

I fitted mine on the weekend (I did a fairly detailed review but yet to upload the video). Long story short, its not a bad upgrade but the differences are not huge. It does make response sharper particularly in sport+ but its certainly not a night and day difference.

Maybe it's time to do a little research on 'stepper motors' or 'stepper motor response rate'. There has to be limits as to how fast they can respond, either physically or accurately enough to avoid throwing codes.


Norm

Nope, they can make drive by wire pretty precise. If there is any limit, it's going to be the servo degrees/sec.

spiller said:

I fitted mine on the weekend (I did a fairly detailed review but yet to upload the video). Long story short, its not a bad upgrade but the differences are not huge. It does make response sharper particularly in sport+ but its certainly not a night and day difference.

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Spiller is yours a premium model? Could it be base GTs benefit more from the device? The more I drive my GT I realize what a big difference it has made. Heck my idle is even more throaty. ..and I was getting close to selling or going boosted I was so disappointed in the past performance. Just to say, Im not here to plug the product and have been just as skeptical about doing the mod but it is something I should have gone for early on.

JKL1031 said:

Nope, they can make drive by wire pretty precise. If there is any limit, it's going to be the servo degrees/sec.

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At some point, the rotational inertias and accelerations involved will set an upper limit to the number of deg/sec that can accurately be achieved. Physical limitations rather than electrical/electronic.


Norm

hiccup said:

Spiller is yours a premium model? Could it be base GTs benefit more from the device? The more I drive my GT I realize what a big difference it has made. Heck my idle is even more throaty. ..and I was getting close to selling or going boosted I was so disappointed in the past performance. Just to say, Im not here to plug the product and have been just as skeptical about doing the mod but it is something I should have gone for early on.

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[MENTION=16086]hiccup[/MENTION] yes mate here in Aus our cars come spec'd as premium performance pack. Don't get me wrong, I am not going to remove it from my car and there is an improvement there (it spins up the tyres with much less input in the rain), it's just different from what I expected. I expected it to be a lot touchier. Not a bad thing that it isn't. I imagined the initial touch to the pedal would be a lot more responsive - the initial lag is still there and feels unchanged but the second phase feels improved. Does that make sense?

I purchased one (used/cheap) just to check it out. I have found some limited benefit for its use with throttle blip on downshifting, and (with a tune) I less often find the need to use my drive mode selector.
Orher than that.....there's not much to it.