SAFCII Problems

[Cool Mr Steve]

I have 550cc injectors and all supporting fuel mod's (check out my profile for everything else). My problem is, when I hooked up my SAFCII after installing the RC 550's, my SAFCII settings have little or no correction (I'm actually adding fuel) in order to make it run smooth and have my fuel trims correct. What is going on?

 

[FastGS-T]

550cc injectors aren't easy to tune. And you dont have a maft? First things first.
(450/550) - 1 = -18% so -18% across the board on your AFC should be the equivalent of what 0% was with your stock injectors. I use a maft so i set my injectors with the maft and so my afc is always at 0% so I dont have to keep calculating a new base.

Even though your fuel trims are correct on your logger. It may be so rich it isnt reading correctly. put it at -18% and then try tuning it. good luck

 

[FullyBuiltDSM]

youll need to lean it out but you need a wideband or dyno runs to perfect it

 

[Sharkcus]

Welcome to my world. I have had my injectors cleaned/benched. New plugs. I do have stock wires, when I get my car back together, I will throw the accell's in that I just bought. I have to run at like +5% with 550s to get it to stop misfiring, and it still misfires a little bit even at that. If I set it to -18% i get a misfire code. I have no air leaks. Everything worked before 550s. I am stumped. any thoughts?

 

[Cool Mr Steve]

Yeah, this kind of sucks. I don't know if it is safe to do the "lean it out to 18%" thing, is it? I don't want to destroy my car, but it seems like something needs to be done. I don't have a wideband, and I don't have any plans to get one any time soon. Anyone have any other ideas?

 

[flacopower]

You have a 95 so you should just go with dsmlink.. Have you done the 'blue wire mod'? If you have, then it should give you a pretty decent idea of where your a/f ratios are..

 

[Cool Mr Steve]

I'm not going to go with DSMlink because I don't have the money. I haven't done the blue wire mod, but I have heard that it isn't recommended. Does anyone have any idea why my car might be doing this?

 

[Sharkcus]

I got my tranny out, I am just waiting for parts now. I'll be able to get it all back together in the next few weeks and then I can tell you if the plug wires fixed it.

 

[dub2gsx]

Not all cars are going to react the same so -18% might not be what it needs! Most people go different routes with their mods and every alternation is going to change what curves you may need! That's a good point to start from with 660's, but with 550's try starting from -10%! Or you can just use this to help you:

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

Try starting from scratch!
Plus a 255lph fuel pump is kinda big for 550's, that could make tuning a little harder.

 

[Sharkcus]

Not all cars are going to react the same so -18% might not be what it needs! Most people go different routes with their mods and every alternation is going to change what curves you may need! That's a good point to start from with 660's, but with 550's try starting from -10%! Or you can just use this to help you:

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

Try starting from scratch!
Plus a 255lph fuel pump is kinda big for 550's, that could make tuning a little harder.

I understand what you are saying, but I do not that that is our problem. I end up having to ADD fuel to get it to even idle without throwing a misfire CEL. I had my injectors cleaned and benched and they flow just about 540cc. That should be right near %-18, not anything positive. Yes, all cars are different and not everyone is going to get a -18. No air leaks... I think this problem goes beyond the basic stuff. I have a 190lph pump w/ rewire mod. New Fuel filter. My pressure is exactly what it should be at during idle (I have a fuel pressure guage)