[frankmehta]

Greetings, everyone!
I am running multiple threads currently on the two cars that I own, My VW Polo GT TSI:
http://www.team-bhp.com/forum/test-d...lo-gt-tsi.html

and My much-talked about Honda Brio, which I have successfully converted in to a Honda CRIO, since I am running a 1.5 litre Honda engine in it:

http://www.team-bhp.com/forum/test-d...ty-engine.html

http://www.team-bhp.com/forum/modifi...injectors.html

As far as I see it, both these cars in their current avatars suit my requirements well, and after all these extensive modifications in less than a year, I have arrived at a balance between what I need, and what they're delivering.

I have owned 6 cars before these, and most of them have drive-by-wire throttle. DBW Throttle basically eliminates the 'cable' driven throttle control, where there is a small crude metal cable that 'tugs' against a mechanical contraption that then opens and closes the throttle body. When I say it's crude, it's actually just a cable connected from the A-Pedal all the way to the actuator which controls the butterfly valve of the throttle body.
Somehow, I have always liked a cable sending my inputs, than actual sensors that exist in DBW cars. The throttle position sensor takes electrical inputs as to how much you're depressing the accelerator and sends electric impulses to the ECU, which then informs the throttle body, and that varies the butterfly opening, along with informing the fueling components to let in more or less fuel. Sadly, all this takes time and is not as direct as you operating via a manual, cable activated throttle body. Also, the sensors dumb down your inputs and sometimes, these silly sensors take their own sweet time and use their silly 8 bit brains to interpret something as emotional as a throttle input. It's just plain sad.
But somehow, emission control and fuel efficiency concerns, along with the reliability of an sensor controlled input, as opposed to a mechanical one, most engines now have a DBW throttle.
Annoyingly, the lag between the inputs and outputs of the DBW throttle leave a lot to be desired.
You JUST can't allow something as dramatic as a throttle input to be dumbed down by a few sensors and expect me to sit quietly about it!

I always wondered if it's the engine that takes time to respond, or the corresponding electronics concerned with that are numb-skulled.

I decided to push the envelope and try a contraption that had been overdone before, but this time around, I had been assured that it was not the 'same old' technology and the statements had some credibility to them.

I am talking about something called a PedalTune by TTS Auto, that specialises in modifying German cars, esp Mercs, Audis and VWs in an unconventional manner, with a maturity that we are yet to see in the Indian market.
http://ttsauto.eu/index.php?route=pr...1&product_id=1
Their products did seem a little new to me to be experimenting too much, but this PedalTune is a simple plug and play device that fits between the throttle pedal and the throttle position sensor, both located in the passenger cabin.

It took me less than 5 minutes to install it on my own, and all I had to do was remove the connector from the TPS and place it into the PedalTune, and the corresponding cable from the pedal tune would fit into the stock connector that goes to the ECU. Easy as Pie.
In the Honda:

In the Polo:


The PedalTune comes with a wired remote that has three basic settings, Economy, Sport and Race. Each setting has 7 different levels of variation. The no. of settings becomes an unnecessary 21, but if you really want the snappiest of responses, I would keep it on full (requires experience, and a lot of respite while pressing the Accelerator)














Well, that's information about the product. Question here is, how did it pan out for me?
I was very very skeptical about the product before I installed it and I always thought it would be just one of those 'forum boner' or one of those 'fake electric gadgetry' type of products that would be more show and less-go.

I installed it in my Polo, as my Crio was at KS Motorsport for some minor work. Started the car and all seemed normal. Nothing abnormal, just a light in the remote. I set the remote to RACE and the top Setting, thinking that it would not make a difference, and set off gingerly by putting the car in 'D' mode.
What ensued cannot be expressed in words. I was shocked at the alacrity with which my throttle was responding. It's almost like someone replaced the DBW with a super sensitive cable operated system. The best part was how early I felt the power! It was unbelievable. The car feels 'lighter,' 'responsive,'and extremely good to drive in the city. I am amazed at how this works, but I can't seem to understand how it can make so much of a difference! My drive is transformed!

Basically, the PedalTune 'fools' the electric drive by wire system into acting quicker, but according to TTS, it's not just that. That can be done by a resistor between the accelerator and the TPS. This system is CLEVER! It sends the right response for fueling, and messes with the ECU's head to do everything, just right. IMMEDIATE power-on-tap makes the car feel so sprightly and almost like someone has replaced the regular fuel with high octane fuel, shifted to sports mode on the gearbox!!!
OF course, the car is not going to be any faster, or there will never be power gains, but how amazing the car drives at part throttle has to be believed!

I have asked for the PedalTune for my Honda Crio now, and I shall gladly update you on the same, but from my current impressions, the 'dumb' Honda DBW system could definitely do with this contraption.

Some dyno figures of the Pedal Tune on an Audi. Somehow, this system gave them impressive power gains. I am speechless!!! I will dyno my Polo this week and come back with my numbers and see if there is any power gains. Well, if there are any, I won't be surprised!








PS: Special thanks to Mr. Naresh Virkar of TTS Auto in convincing me to go in for this product. It took a lot of convincing, as I have seen other types of these 'electronic fooling devices' and they were not my way of improving my car's performance. I heard his claims and asked him to send a unit over. I haven't paid for it yet, but I will be paying for two of these units for sure. One for the Polo and the other for the Crio!

[IshaanIan]

Woah. Frankmehta sir, I must thank you once again for proving that 21st century cars can still be made to be fun. Throttle response from these drive by wire systems has always remained an issue for me in stock cars these days including my Kizashi. Hats off to you for doing your homework and testing such stuff out. Could you please share the cost of this unit? Does it vary from car to car?

PS: this definitely has to be the best piece of news I have heard this week

[frankmehta]

Originally Posted by IshaanIan

Woah. Frankmehta sir, I must thank you once again for proving that 21st century cars can still be made to be fun. Throttle response from these drive by wire systems has always remained an issue for me in stock cars these days including my Kizashi. Hats off to you for doing your homework and testing such stuff out. Could you please share the cost of this unit? Does it vary from car to car?

PS: this definitely has to be the best piece of news I have heard this week

I am extremely impressed with this product. It's been a few weeks since it's installed in the car.
It costs 16k. I've got a lot of PMs and I've given the contact details of the person. I have no commercial involvement with him so you will have to figure your rates ourlt with him.

As for the Kizashi, I am sure he may have the product. All you need to do is to bend down and take a photo of the connector going into the module next to your accelerator. Even better if you open the clip and show a photo of how the open connector looks.

[GTO]

Thanks for sharing, Frank! Great one.

Am told that a lot of newer cars with ECO / Normal / Sport modes use a similar solution. Quick & relatively cheap way of 'different' driving modes for car manufacturers.

[Dr.Naren]

There is something called drivers wish map in ECU. It's a table with Accelerator pedal position, RPM and injected quantity of fuel in mg/stroke ( Torque in NM for modern ECU). Basically in a good remap, tuner changes this map which leads to better throttle response.

ECU depends on the data from various sensors. These sensors are usually rated from 0-5V. Tuning boxes/ pedal tune boxes send a lower voltage value to ECU and fools it. ECU looks up at respective map tables and delivers more fuel.

For cars which cannot be remapped, PedalTune looks like a good option for crisp throttle response.

[Dusk Tiger]

Hi, very interesting mod. Great job. Can you elaborate on how exactly you sourced the product? The website doesn't seem to be functioning properly as the price is always 0 euros even after adding it to the cart. Also is it universal? If not how did you choose one for the polo? I am looking to get one for my polo 1.5.

[karuvally]

Dear Sir, Thanks for sharing this info
I was wondering if you tried that economy option. I would love if I could have less responsive pedal input in my car.

[ecenandu]

Originally Posted by GTO

Thanks for sharing, Frank! Great one.

Am told that a lot of newer cars with ECO / Normal / Sport modes use a similar solution. Quick & relatively cheap way of 'different' driving modes for car manufacturers.

Hmm, highly unlikely. OEM solutions could be based on software, like different MAPs, offset values etc.

I'm curious to know how this gadget works though. So here is my hypothesis,
let us say the normal pedal travel is from 0 (accelerator not pressed) to 100 (accelerator fully pressed)

Eco mode: Accelerator 0 to 100 , data send to ECU 0 to 85

Normal mode: Accelerator 0 to 100, data send to ECU 0 to 100

Sports mode: Accelerator 0 to 80, data send to ECU 0 to 100

So, basically, it is reducing the pedal travel by fooling the ECU. Anyway, it is quite easy to test this, all you need is a multimeter.

[Dr.Naren]

I am not sure if Pedal tune box can provide better numbers on paper. It just fools the ECU to request more fuel at particular A pedal position.

Suppose at 50 percent throttle position, if ECU requests more fuel, say same amount at 100 percent throttle position - "Better Throttle Response ".

Now why do I say this won't have any power gain?

Drivers wish map is the one which ECU looks into to request fuel based on throttle position.

Suppose at particular RPM,

50 percent throttle position - 50 mg/stroke

100 percent throttle position : 70 mg/ stroke

Now with a pedal tune box, ECU will receive manipulated voltage values and would think 50 percent throttle position is 100 percent and obviously request more fuel. So at 50 percent throttle you are having the same effect as 100 percent throttle. Now even with fooling ECU if you request more fuel than throttle position at 100 percent, this is not going to happen because of various other limiter maps in ECU like torque limiter map, smoke map etc.

[ecenandu]

Originally Posted by Dr.Naren

Now with a pedal tune box, ECU will receive manipulated voltage values and would think 50 percent throttle position is 100 percent and obviously request more fuel.

That is what I think, Naren. Moreover, these pedal sensors usually have two potentiometers for redundancy. The one I have seen, sensor A changed voltage values from 0 to 5V, where as sensor B was inversed, 5 to 0V.

Originally Posted by Whiplash7

My best guess is that normally the pedal position sensor changes are slowed down(filtered) by the ECU and the pedal box must be simulating a faster change to the ECU.

Do you work for any OEM supplier?

I have written a strategy for ECO mode by just using a TPS filtering for forward pedal direction and no filtering while releasing the throttle pedal. This one was for a bike, though.

[Whiplash7]

Originally Posted by frankmehta

I installed it in my Polo, as my Crio was at KS Motorsport for some minor work.

Does the same pedalbox fit for both your cars (polo and Brio), I mean do they have the same Pedal connectors?

My best guess is that normally the pedal position sensor changes are slowed down(filtered) by the ECU and the pedal box must be simulating a faster change to the ECU. For example, if you press your pedal down 10cm in 5 sec, the ECU filters this signal and sees that you have pressed the pedal 10cm in 7 sec. Now pedalbox must be simulating an input of 10cm change in 2 sec and hence the ECU sees it as 5sec. Obviously OEM do this to improve fuel efficiency.

But I hope the pedalbox is manufactured as reliably as the actual pedal itself. imagine what would happen if the pedalbox suddenly gives a higher voltage due to some short-circuit inside and this happens in slow city traffic, the consequences could be fatal. I would suggest not to use it for your everyday ride.

[Dr.Naren]

Originally Posted by ecenandu

That is what I think, Naren. Moreover, these pedal sensors usually have two potentiometers for redundancy. The one I have seen, sensor A changed voltage values from 0 to 5V, where as sensor B was inversed, 5 to 0V.

Yes, I agree. Most of the sensors are rated from 0 to 5V. Tuning box manipulates this and sends wrong values to ECU.

Originally Posted by Whiplash7

Does the same pedalbox fit for both your cars (polo and Brio), I mean do they have the same Pedal connectors?

My best guess is that normally the pedal position sensor changes are slowed down(filtered) by the ECU and the pedal box must be simulating a faster change to the ECU. For example, if you press your pedal down 10cm in 5 sec, the ECU filters this signal and sees that you have pressed the pedal 10cm in 7 sec. Now pedalbox must be simulating an input of 10cm change in 2 sec and hence the ECU sees it as 5sec. Obviously OEM do this to improve fuel efficiency.

This has nothing to do with time buddy. I mean ECU doesn't consider the time factor here. For A pedal position and injected quantity of fuel at particular RPM, ECU looks up at drivers wish map. Now with a pedal tune box, ECU gets fooled and would assume 50 percent throttle as 100 percent.

During a good remap, drivers wish map is changed. If you request more fuel at 100 percent throttle position, it gets limited by other maps in ECU. But with a remap, you can change those values too. This is the reason remap always wins over tuning boxes. You get total control over the car. But a bad remap is very very harmful!!

Pedal tune box / changing values in drivers wish map via remap is totally safe. This doesn't translate to better gains on paper. You just require lesser throttle response.

Frank, Do you find any difference at 100 percent throttle with pedal tune box?

[ecenandu]

Originally Posted by Dr.Naren

This has nothing to do with time buddy. I mean ECU doesn't consider the time factor here. For A pedal position and injected quantity of fuel at particular RPM, ECU looks up at drivers wish map. Now with a pedal tune box, ECU gets fooled and would assume 50 percent throttle as 100 percent.

Hmm, it is not that simple as you think, Naren. There are a lot of ways in which ECU can consider the time factor. For bikes, we had transient fuelling, which considers how fast the throttle is moved and based on that it will add additional fuelling on the steady state map.

For transient, we had one fuelling table for fast transient and one for slow transients. For cars, which requires drive by wire, I think more complex strategies will be present.

[frankmehta]

I must add. I never use 100 percent of throttle. But I know for a fact that at FULL RACING MODE on the remote, there is lesser amount of usable pedal travel. Naturally, after some amount of throttle input, the pedal must be maxing out the signal to the ecu, which means the remaining part of pedal travel (maybe the last 20 percent) is useless at full settings.

[Whiplash7]

Originally Posted by frankmehta

I will dyno my Polo this week and come back with my numbers and see if there is any power gains. Well, if there are any, I won't be surprised!

Please post before and after dyno results. Have fun.

Originally Posted by Dr.Naren

This has nothing to do with time buddy. I mean ECU doesn't consider the time factor here. For A pedal position and injected quantity of fuel at particular RPM, ECU looks up at drivers wish map. Now with a pedal tune box, ECU gets fooled and would assume 50 percent throttle as 100 percent.

I'm skeptical with your explanation since by simply adding an offset position you would create a dead-band near 100 percent. It would also make it tough for the driver to control the pedal, since you practically reducing the pedal travel distance which maxes out at a lower pedal position.