The DFI cars as an example have 8 levels of timing. Level 8 would be the top of the stairs in the timing or the top floor. All levels below and the top floor can be modified. Multi level timing was introduced by Bosch in programming in 1985 so it does exist and is not new. This also does apply to 996TT,997TT etc yet not on the same level as the DFI as they have all advanced since the introduction. The parameters that these levels are controlled by are also programmable and all code can be changed.

Take a look at WhiteKnight(s) times just posted 60-130 as a 997TT Tip as an example.

Best Regards,
Scott Slauson

 

I would love to know how hard it would be to have numerous maps loaded on a rom that switches via the controls in the cluster like APR does on B5 S4s. That would be great.

 

I guess that would depend on if you wanted it automatic or switchable manual by stalk. Both scenarios now exist yet perhaps differently by tuners.

Best Regards,
Scott Slauson

 

switcable bt stalk.

 

OK it can be done yet is more specific by the tuner you stated. Keep in mind it is not done by all tuners for specific reasons relating to warranty.This though would be irrelevant when flashed back to 100% stock as per Porsche.


Best Regards,
Scott Slauson

 

yup, but please enlighten everyone as to how the ecu determines which "level" to be in. The aftermarket ecu's use a "trigger" event to knock it back a bit. Almost all aftermarket ecu's since the late 90's have that capability. Most have a slew rate based on the intensity of a knock event, or series of knock events in a short time.

I wasn't talking multi level timing, I was talking predictive and time based timing which does not exist in the 996TT ecu. I believe Nissan was one of the first to implement it followed by BMW(time before TDC or firing event). This allows a "window" of ignition advance to either advance or retard the firing event of individual cylinders based on octane, load, etc. Since the 996TT doesn't have this capability, you would have to completely change the strategy that the ecu uses to determine advance. The best option for the Porsche world is manually changing maps via a stalk(as you mentioned), or a series of events that the ecu can recognize. Both of which would also allow for a valet mode(4k rpm rev limit). This does increase the liability however as if the customer forgets to switch back to a pump gas map, things could go awry.

justin

 

I agree 100% with you. I would like to mention that most of the ignition timing carrection factors in motronic are pulluing timing even on good 93 oct fuel(non-cali). So you are not adding timing by running good race fuel or additives, but you are reducing the amount of timing pulled in the correction factors. Just something to consider. The car corrects timing by knock activity, and I wouldn't be surprised if by other values too. The codes are maps inside of maps inside of maps.

Motronic is way more complex than just running Win OLS and reading and changing maps. They are really difficult to interpret. Some tuners in the past have gotten by by modifying just the right amount of boost, fuel and timing maps to make the car fast. It is very difficult to not only understand what all the maps do, but also change them in a way to get what you want without screwing other things up. Their are maps that are never touch because tuners do not know how to make them work after changing them. It isn't because the tuners are not good at what they do. It is because it is way to much to know.

 

The maps are usually load vs rpm, load, vs. engine temp. etc etc. thus we can dial in a pump as well as race gas on one file... the timing numbers for example on pump at .8 bar will not be the same as on race at 1.5 bar... so we can control it because its load based...

 

correct, as an end all, be all. We do the majority of tuning this way even on standalones, but it needs a way to adjust the boost. Incidentally, the midrange and lower end loads will ultimately have pump fuel timing, and therefore not 100% optimized. It is the easiest for the customer though. Unless one of your customers is powell, of course.

The other reason that this can lead to issues is when the boost is out of control on pump fuel, someone cranks up the boost, etc. You are then relying on the knock sensors to reduce timing and can lead to issues.

Justin

 

Yep, but being street cars its the best of both worlds... I have seen the cars with the map switcher for fuel ... the boost stays the same yet the timing numbers change... yet those set ups cant control the boost as we do with the EBC...
Im not for or against either.. just learning as I go...

 

And this why im going to E85 ..