General Need advice on tuning with MAFT *AND* SAFC

[Tsi4me]

Ok, I have looked around and tried my best to find a 'guide' to basic dsm tuning using a maft and a safc. I have only found one or the other. I am about to pull my hair out or beat the crap out of this car if I can t get it running decent sometime this year. Here is the scoop, the full rundown, hopefully it can help. I have been building the car for the past 2 years, and in that time have only driven it around the block twice, (see why im so aggravited now) anyway here is what I have, then I will list what I know (datalogger). 91 TSi FWD 5spd. Bored 40 over, 8.5:1 CR, everything lightened and balanced, stock size valves, stock cams, currently have 450's in place, but have 550's (was running rich so the 450's went back in), aem afpr, holly fuel rail, 6an lines, dejon tool blowthrough uicp, 3" gm mas, sm 16g ported & clipped 10, dump tube o2 housing, stock sidemount (yuck), stock fuel pump. All tuning at this point is for base or idle, the car hasnt made it out of the yard for me to even think about mid or wot yet. I have the base fuel pruessure set to 38psi & using the jet that came in the afpr from the factory. I have the maft set for 450's and the idle knob set on 1, rpm wire is connected, but has not been setup. My datalogger (mmcd and or palmnstein) shows my fuel trims around 160-170 which from what I read is real high. Is it normal for the trims to not move much when datalogging ? They pretty much stayed the same. Right now the safc is base line across the board because anything I tried made it run like crap. Can anyone give me some good #'s to start with so I can play with it some more ? Right now it is running hella rich and that sucks. One other thing is the gas that is in the car is proably close to a year old, but still ignites fine. Anyone wanna come to chesapeake, va and help me get this right ? Cash talks $$
Also what is more usefull, an egt or an a/f meter ? I need to install something other than the datalogger, but at this point Im not looking for performance, just basic driveablilty.

 

[kpt4321]

SEARCH SEARCH SEARCH.

http://www.dsmtuners.com/forums/showthread.php?t=137432&highlight=safc+maft

http://www.dsmtuners.com/forums/showthread.php?t=122516&highlight=safc+maft

http://www.dsmtuners.com/forums/showthread.php?t=83748&highlight=safc+maft

http://www.dsmtuners.com/forums/showthread.php?t=128938&highlight=safc+maft

Those are just topics with "SAFC" and "MAFT" in the thread title.

In addition, there is a TON of information out there about how to tune your car with the fuel trims.

http://www.dsmtuners.com/forums/showthread.php?t=58403

http://www.dsmtuners.com/forums/showthread.php?t=105569

http://www.fullthrottletech.com/forums/showthread.php?t=105

Keep in mind that from the point of the ECU, tuning the SAFC and tuning the MAFT do the EXACT SAME thing.

 

[Tsi4me]

I will read those threads, I was also looking for some vehicle specific advice, as it seems all the threads say every car will be different. Also all I have is a datalogger, is there anything else that I can get that is afforadble which will help me tune ?

 

[kpt4321]

Let's see, what else.

Long term fuel trims can't be 160, O2 trims can.


EGT information:

http://www.dsmtuners.com/forums/showthread.php?t=41270&highlight=egt


And Narrowband AF Gauge Information:

http://www.dsmtuners.com/forums/showthread.php?t=144581

http://www.cmperformance.com/techinfo_oxygen.html


And here is a thread asking the same exact question you did:

http://www.dsmtuners.com/forums/showthread.php?t=5844&highlight=egt


There is way more information out there, but I am not going to find it for you.

My answer is skip EGT and AFR, and buy a logger. That is THE ONLY way to tune a DSM.

Did I mentioned search yet?

 

[kpt4321]

I will read those threads, I was also looking for some vehicle specific advice, as it seems all the threads say every car will be different. Also all I have is a datalogger, is there anything else that I can get that is afforadble which will help me tune ?

A datalogger is all you need to get a pretty good tune.

What do you mean, vehicle specific advice? We all have DSM's here, any more specific and we talk about everyone's car seperately, which is a big waste of time.

You want to use the logger to tune the MAFT and/or SAFC (that is up to you) such that you achieve the goals stated in the many many guides (no knock, 100% fuel trims, etc, etc).