Thread: How to make your fuel and timing maps AKA "TP/LOAD" scales

i think your thread has exceeded its usefulness... and will probably get you banned.

what a shame.

He said call him retarded, so I did, I hope he knows im not really meaning that in a real mean spirited way cause im not, he's learning to trust I know this shit is like learning chinese. But its quit crystal clear TP 44 in near zero 99% os the time, he must have had a brain fart or looking at something in a really wrong way to draw that conclusion, its not debateable its fact.

I'm told Vadim has lots of N/A logs of TP. He said he'll post a log from an N/A car at WOT (so we know pressure will be constant around 100 kPa for the entire log) and we'll get to see TP values throughout the rev range. This should put a few things to rest pretty quickly.

This is a bunch of malarkey. You can't tune an RPM/TP indexed map the same way you tune an RPM/pressure index map. You can't treat TP as a half-assed load scale. That will just get you confused. And it is exactly why we're having a debate here. The fact that TP changes with temperature makes complete sense and is not something you want to "work around". It is something you need to understand and then you'll realize you can basically ignore it.

Once you really internalize that TP follows the torque output of the engine, you'll see why you don't have to fight it. It just takes a different style of tuning.


For example...

You should really be thinking of the TP numbers like a torque output number. Triple the TP number and think of it as wheel torque if that makes you feel better. Now you'll see you have a map indexed with RPM and torque.
What timing do you want at TP=10 (Torque= 30 ft-lbs)?
What timing do you want at TP=20 (Torque= 60 ft-lbs)?
What timing do you want at TP=30 (Torque= 90 ft-lbs)?
What timing do you want at TP=40 (Torque= 120 ft-lbs)?
What timing do you want at TP=50 (Torque= 150 ft-lbs)?
What timing do you want at TP=60 (Torque= 180 ft-lbs)?
What timing do you want at TP=70 (Torque= 210 ft-lbs)?
What timing do you want at TP=80 (Torque= 240 ft-lbs)?
What timing do you want at TP=90 (Torque= 270 ft-lbs)?
What timing do you want at TP=100 (Torque= 300 ft-lbs)?


The RPM scale could almost be done away with entirely. It is really only used to compensate for the fact that if the engine is moving slower, you will need to ignite the mixture a bit later than when the engine is moving faster, given the same exact amount of air/fuel in the cylinder.

I dont know what its going to put to rest but sure post them up but the info would be tons more value about if he can log vacuum so you would know what in/hg equals his TP for his setup. Being boosted you quickly run out of vacuum sure I could easily drive in vacuum mode but my car is gonna whip right through vacuum a shit load quicker than any NA thats just because of the turbocharger making it alot more efficent.

All your gonna see is that it pegs out at zero or very close to zero in/hg and it will have a related TP and he may actually fall a little maybe to 1-2 in/hg or more and the resulting TP will reflect this but you have to be abel to log it to see it,

TP does change with tempature but not all crazy and out of wack, it changes just about as much a barometric pressure or a change in elevation oh well lets give it about .5psi credit for change big deal it doesnt change much. Im sure if I knew how to actually scale a MAP sensor to make up for these difference's my TP would always match 99.9% of the time instead of 99% of the time.

UNISA JECS, what if instead of what you've described above, the log shows similar to what I posted in my second reply?





Would that not be surprising to you?

That would be freaking amazing

I dont think even the best modern engine pull a perfect vacuum at WOT, they get close to it ofcourse but most people never use a MAP sensor to log there NA engine which would be a good tunning tool to see if the mods you have made get you closer to a perfect vacuum.

When my engine was N/A and 100% stock from air filter to tail pipe including a stock (restrictive) MAF in place, I logged around 96 kPa at WOT. This is with a properly calibrated MAP sensor based on local weather station data.

Now that things are a bit less restricted, I see a little higher, maybe upwards of 99 kPa (before the turbo starts to do its work of course).

I am of course, at sea level. Those above sea level obviously never get that close. And those below sea level... Well, no thank you. =D


But that's not "a perfect vacuum". That's almost perfect ATMOSPHERIC (sea level) pressure. I have no idea why we'd be talking about pulling a perfect vacuum in this thread.