Increasing Horsepower
#81
06-19-2018, 04:00 AM
I have the VAP tune on my R without the pulley and it certainly does make a difference... for rear wheel drive its about all the tires will handle under most conditions, even the PSS tires. Of course you have the pulley as well for even more power.
The 55 or so horsepower is not a huge lift over stock, however the remap they do on throttle response really brings it home. In my experience you get used to it and may regret if you tone it down.
Lawrence
The 55 or so horsepower is not a huge lift over stock, however the remap they do on throttle response really brings it home. In my experience you get used to it and may regret if you tone it down.
Lawrence
Of course some people love very sensitive throttle too, hence why products lime sprint booster and pedal max are popular, we all like different things and aspects of our cars, keeps the world an interesting place.
#82
06-19-2018, 09:18 AM
Senior Member
I don't disagree with any of that but, as I said before, everything you are describing is happening in the cars computers. The Accelerator Pedal Position sensor (APP) is just a twin track potentiometer that receives two independent power supply from the ECM and sends two independent analogue signals back to the ECM.
One track outputs half the voltage of the other so that they can be checked against each other to make sure the signal is correct. Changing the potentiometer so that the voltage changes in half the time isn't going to magically override the ECM which is what the original discussion was all about. All you end up with is a very twitchy and sensitive throttle.
One track outputs half the voltage of the other so that they can be checked against each other to make sure the signal is correct. Changing the potentiometer so that the voltage changes in half the time isn't going to magically override the ECM which is what the original discussion was all about. All you end up with is a very twitchy and sensitive throttle.
I agree that the gadget that plugs into the potentiometer is bogus, all it probably does is have a different stepping on the resistance. That is just a scam
The one that plugs in the OBDII does instead affect the CPU in such a way that it opens the throttle faster and fully most likely by taking the reading from the accelerator pedal position sensor (the potentiometer) and then tweaking other sensors in order to bluff the opening variables.See here: https://www.racechip.us/throttle-tuning/xlr.html (SCAM) -
As far as the F-Type goes, when in dynamic mode, with the ENGINE setting in dynamic, it does exactly that, the first half of the accelerator pedal seems to control 70% of the throttle
My point was, the scam that plugs in the potentiometer (pedal position sensor) is BS but the real ones that plug in the OBDII do actually work
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ndabunka (06-19-2018)
#83
06-19-2018, 07:20 PM
Veteran Member
We agree on the first point then. Do you have any links to the OBDII devices you are talking about or do you just mean the ones you get from places like VAP that reprogram the ECM?
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