Tune comparisons

[charliex]

Since Whiskey asked, i'm going to post up the differences between our tunes and the others, i used to say they're pretty much the same, but now i've seen most of them, i am no longer going too.

This information is based on the last tunes i saw from the competition when i replaced their tunes, only 6 replaced so far, and they may have changed it since then, this would have been within the last month.

First off you can verify this stuff yourself, a good OBD II scanner will tell you the firmware ID used, this will tell you if its an old tune, or an NA tune.

Most of the aftermarket SC kits i've seen use outdated tunes, usually the first firmware revision for the 06 and then mid to early on the 05, a couple use the 2004 05 tune from the old 2004 240 (not the new ones), all of these have significant problems, don't believe, well why would you right, good, don't, go to your dealer or the lotus tech site and read the dealer reflash bulletins that are available for those early firmwares. the most recent ones have the DBW fixes for people that get phantom DBW error codes.

Secondly for some odd reason*1 they're using NA based firmwares for SC cars, this has multiple issues but the biggest problem is that there just are not enough breakpoints (resolution) in the maps to accomodate the supercharger tuning correctly, the VVTLi profile is setup for the NA engines, no variable cam, the knock detection maps aren't setup correctly for the profile or extra noise generated by the supercharger.

I'm going to stick to just the differences between NA, SC , old and new tunes and not specific problems in the competitors tuning.

The first two images are the difference in map size between an NA car and an SC car, the smaller is the NA map, this happens for most of the important maps in the system, its imperative that the larger map is used for the supercharger, again you don't have to take my word for it, its easy to find out.

*1 well it used to be an odd reason for me since i always though if they'd cracked the protection algorithms why use the old firmware, i'd never even seen the first rev til recently, and the reason is because its not protected, so you don't need to reverse engineer the protection algorithms in the old firmwares.. They're probably also using NA tunes since the SC cars have different sensors and you have to reroute them for the aftermarket kits (or add the new sensors), one of the reasons my older 06 katana shows -40C on the IAT OBD II is because i missed that one location when i rerouted them so its showing the missing sensor, and -40C is the limit of the AD convertor since its open circuit, thats since been fixed, it doesn't affect anything other than the OBD II readiness codes or reading the IAT via a scan tool, the bits of the tune that matter use the correct sensor.

[Whiskey]

Thank you Charliex. I hope this thread doesn't become poisoned with opinions that can't be backed by reproducible data. I know you have a product to sell, maybe even through Fred in the future, and that your work is respected.

Most companies can't fight the onslaught of allegations from competitors, but I hope this iteration of the debate can be data driven and not a smear campaign against PES. Don't they have a spokesperson from their side explaining the details and assuring their customers that the tune was carefully created for the BWR SC? You can't answer for them, and maybe they do have someone. I need to use the search button to find answers. I know they are on vacation this week, so don't expect many responses to your findings from PES.

[exarkun1178]

[charliex]

Exactly why i posted like i did, I'm giving you the data that you can verify, the older tunes also allow you to use my software that i've given away for ages to download and verify what i am saying for yourself, its really not rocket science to verify it, i do run the risk of giving a leg up to the competitors by giving them more information about why its not working properly, same as happened with the DBW fault, but my goal is having people with properly running cars, i don't sell tunes to make a living i do it for a side project , because i enjoy it usually, and it lets me buy neat tools i wouldn't normally have a good enough excuse to buy.

I didn't give any of the specific problems i've seen in the PES tune, i left those parts out and left it generic SC vs NA, the maps i posted are from the generic tunes.

The simplest way to backup what i'm saying is just plug in an good OBD II reader that can show the ID, and it will tell you what revision of the firmware you have, you can then download a NA tune from an NA car, and your tune from a BWR car and just do a simple comparison and you'll see the lack of changes, you just have to match the base firmwares to make it easy.

The question on whether or not you need more breakpoints (cells) to properly tune an SC car vs an NA car can also be answered by an independent person, same for VTTLi mapping, same for the knock sensor, just ask if the knock sensors need to be recalibrated now there is additional noise from the supercharger.

I'm not really sure you'd get a technical debate from the other sides, it'll go more along the lines of 'internet forums etc', charlies just a video game programmer( lets swap jobs sometime, see who does better ! ), they've been in business XX years so it must be good, call you and tell you not to say anything else, give you a reasonable sounding and compelling talk on why me or my points are invalid (I doubt they'd be of technical merit), that we've had more problems than them, or bring up frank or monkey and say look at the way the informations presented, rather than the information itself, etc etc. All of them i've heard before, and it usually happens the most when when someone just bought something very expensive and has more interest in proving to themselves that their purchase was indeed valid.

However none of the above will change any of that hard coded data inside your ecu.

[Murix]

Charlie, this is good information and glad you posted it. I hope it stays civil and people can digest and understand what you are saying. I for one get the point. Dealing with software for a living, I am always dubious of old bugs causing problems.

[Johnny B]

Using a NA based tune on a supercharged car is like running a 100 meter race in cowboy boots. Yes, you have footwear on your feet, but it's not the right footwear for the task at hand.

Where did Lotus place the alternator on the Exige S? What type of ECU tune do they use?

All you need to know are in the answers above.

[Bavarian Motorist]

So these problems would show in the NA tune as well as in the SC tune, or more particularly in the SC tune?

[charliex]

its two different sets of problems, first one is using the NA base map for an SC car is incorrect, second one is errors in the actual maps themselves.

[NomisR]

Originally Posted by exarkun1178

Wanna share some of that popcorn?

[Bavarian Motorist]

Originally Posted by charliex

its two different sets of problems, first one is using the NA base map for an SC car is incorrect, second one is errors in the actual maps themselves.

How does this affect the end user or the application?

[dma550]

This is painful to read, along with some of the controversy over tunes. Tunes to us (the end user) are pretty much a black box. We don't have the ability to easily look at it and say, yep, it's a good one, or "whoa, what a ticking time bomb"... we need to rely on the experts, and the experts that these experts choose to deliver an effective black box.

As to whose tune is better, makes 1hp more at n rpm, that's something I never cared about. HOWEVER, if one tune can damage my motor because of something important missing, it is imperative that the vendors responsible step up and defend themselves and their integrity, and show their buying public that they are protected, or provide a remedy. My car is becoming even more of a garage queen!

[Bavarian Motorist]

BWR people, Charlie claims his tune is compatible with the BWR kits, so that's an option for you if you're concerned



Personally, I know which NA tune I am going for...

[dma550]

Originally Posted by Bavarian Motorist

BWR people, Charlie claims his tune is compatible with the BWR kits, so that's an option for you if you're concerned



Personally, I know which NA tune I am going for...

That's true, it comes down to paying for something twice as well. Edit... personally I want this right, I am commenting that a tune was already purchased with the BWR kit, and if it is defective, needs to be remedied. If that remedy is another flash from another vendor, that works for me too.

[charliex]

It is difficult to determine what the end results are, it does usually come down to who you believe, most owners start off the same, it runs great money well spent.

Calibrated wide band, known dyno, and good dyno operator with a data logger, measure the AFR's and final spark advance in all the situations you'll drive in, that'll give you a clue.

With my tunes i can ride along with you and measure the knock sensors, spark advance and AFR's that how i do the road tunes, the lotus ecu knows when the fuel is off so it does display it.

I did this recently on a bemani SC, we tuned at the dyno a couple of times, then did a road tune and it was slightly off so a bit of detonation, then we did an hour or two road tuning in vegas and thought it was all gone, but on the way home the owner drove in a manner they normally wouldn't and it showed a bad spot, so i went back and fixed that one too, without the ability to read the knock and afr it'd have been really difficult to do.

Currently i'm a little uneasy swapping out the BWR tunes til i actually get one to a dyno, for two reasons, one i haven't seen a proper sheet on a dyno i know, secondly if there are any issues they often become mine, it should be the same the kits pretty much the same, most of the people running the replacement tune report good news.

[Bavarian Motorist]

Originally Posted by dma550

That's true, it comes down to paying for something twice as well.

Sometimes that happens when modding. You do something you think will work, and then you realize there is a better product or something similar. I did this with my headers and I can't tell you how many things I've paid for multiple times.


But at least you know this is the best

[Reno Elise]

CharlieX,
For us that know nothing about tuning can you give us a very brief overview of what the map is showing and since it is 3d, the labels for three fields? I have your 05 Katana tune and am always interested to learn more about my car.
Thanks

[PhoneBoy]

Originally Posted by Reno Elise

CharlieX,
For us that know nothing about tuning can you give us a very brief overview of what the map is showing and since it is 3d, the labels for three fields?

+1

RPM, thottle position, whatever? I have no idea what I'm looking at - but I'd love to have one signed and framed for my garage wall.

[charliex]

I'll post the map in a more meaningful way in order to explain it.

So this is the primary screen of my software the tuner would work with, the main elements of the map are as follows, (i'm using a diagnostic map here, this isn't in a car like this)

Large coloured text in the middle are the map values, in this case its spark advance values, down the left side we see the MAF values, this is the first lookup value from the mass air flow sensor, the ecu takes the value from that sensor, converts it then and looks down that first column to get the value closest to the sensors reading, that becomes the row it looks on for the rpm.

The column values are in RPM, so it takes a converted RPM value, then indexes to the closest column, now it knows the row and column of the cell it wants to use, a cell being one individual spark advance value.

Just like looking at a TV guide, look across the days/hours, then down the channels, find the show.

the software traces where the car currently is reading and lights up that cell in black, this is on the bench so no input values so its at 0,0, plus i'm in the middle of rewriting the interpolation algorithms, (Currently I run the ecu's interpolation function in a virtual machine/ecu, pass the values and tables in and record the results).

the red and blue markers on the row/columns are where i'm currently editing a cell, which is highlighted too, here i can change the value to whats wanted.

So with that part out of the way, the ecu uses the indexed values from the maf,rpm values to read out the spark advance, or on the fuel map, the injector timing, it then feeds this out, plays around with it a little for the adaptation etc, like adding on a few degrees when the AC is on.

The ecu also does something called interpolation which allows it to increase the resolution of the map by looking at the neighbouring cells when its not on an exact match for the maf,rpm reading against the row/col heading values, this is a bit like going into photoshop and running one of the filters to smooth out an image.

Now the difference in the first two images that i posted are that there are more rows for the MAF sensor on the supercharged cars than there are on the normally aspirated cars, this gives us a greater number of cells to play with and a much finer tune, because of the way the forced induction cars work you need more cells to correctly map it.


You can see the colour of the text map matching the graphs i posted, so as the value gets higher it goes from blue, green to red.

hopefully thats clear enough, if not feel free to ask on a specific part.

[Reno Elise]

That helps a lot. Thank you!

[Bavarian Motorist]

I failed math.