can anyone help out a new tuner

[dugjr24]

I just intalled RC550's a 255 fuel pump and a s-afc. I am on t-25 with 3in turbo-back exhaust, RRE IC pipes, and MBC. I know to do any real tuning I desperately need a datalogger, but is there any mild tuning I can do with the s-afc and be safe. The car seems to stutter since the fuel upgrades. The car feels like it's producing power but the rpm's do not rise steadily. Its almost like the car is bogging under full boost. Its making power but not going anywhere.

 

[evotuner]

if you installed the injectors and your afc settings are still at 0 across the board, you are running pig rich. That is probably the "studder" you are getting. You need to lean things out on the high throttle. Since you don't have a datalogger, for now to get you running decent you will have to tune off the o2 voltage. Slowly take fuel out (2-3% at a time) across the board until your o2 voltage is around .96V, that will make it alteast driveable until you get your hands on a logger

 

[dugjr24]

well is there a more accurate way of reading the 02 sensor than with the s-afc b/c i dont think the 02 readings that gives out is very accurate.

 

[evotuner]

well is there a more accurate way of reading the 02 sensor than with the s-afc b/c i dont think the 02 readings that gives out is very accurate.

The afc is getting the o2 reading from the ecu, how can you get more accurate than that? Tuning with the o2 sensor is DEFINATELY not the best way to tune, but it probably is for now with what you have under your circumstances.

 

[CanadianTSi]

Since Larger Injectors with the T-25 are completly useless, take them out until you actually need them and your life will be 10x easier

 

[My91TalonTSi]

You might also want to consider an adjustable fuel pressure regulator for that big fuel pump.

 

[1993eclipseGS]

I happened to have a new datalogger for sale in the classifieds

 

[dugjr24]

Well I cant put the stock injectors in b/c I had to give them to the guy I got my 550's from, but Ill look a little more closely at the 02 an the s-afc and Ill definitely take a look at the datalogger in the clasifieds. thanks for the help though.

 

[Spln_Hrd]

i would unistall those fuel mods, you are gonna run rich as fudge if you are not leaning it out. do you have anything to watch your a/f ratio with? it should need leaned out a shit ton, but without watching it you could go to lean and detonate or melt your pistons. aluminum melts easy

 

[Spln_Hrd]

sorry for posting something you already knew my computer had an error or something and only picked up your post and nobody's replies.

 

[dugjr24]

I leaned the hi throttle out 15% across the board and it took away the stuttering feel. The car is bringing in about 1470 karman and the 02 is reading between .100-.110 the I know its not good to tune off of the 02 but its all I have right now and someone said it will at least put me in the ballpark.

 

[dugjr24]

another thing according to my 02 readings im (supposedly) still pretty rich. When you guys say smoke will come out of the exhaust sometimes when it is too rich, what color should it be? Im guessing it will smell like gas. cause mine is smoking a little bit.

 

[evotuner]

Sounds like you are making improvements, but it does sound like you are still too lean. Hopefully some 2g guys will back me up (since I have a 1G) when I say for now shoot for .96v-.98v on the 02 sensor.
As for answering your question your smoke out the exhaust should be black/dark grey if you are running rich.