BillRed85

I drove 31 miles last night, mostly highway and used 4.5 gallons of gas!!

The 02 sensor is reading about .7 - .8 volts all the time and the air fuel meter says I'm at like 12:1.. When it idles in gear it spews black smoke out the back, and when I give it some gas it also blows a little black..


Any DFI users... how much change to the fuel map should I make at one time? Any Tuning hints?

Bill

snaketr

Call Dan Baldwin at 804-598-7727. He is extremely busy so be patient with him. He is very good at tuning a DFI. I'm sure he has some programs on disk that he can send you and you can load into your ecm. Do not try change anything in your maps if you are not 100% sure about what you are doing. I know he has some start up programs he did for me so you can ask him about them. However I am sure he will not send them for free, you have to pay for that knoweledge but if you treat him right he will treat you the same. Justin

J Z06

Job Spetter(pronounced Jobe, as in Probe) at turbo people in NY would be a VERY good source of tuning. He used to tune my DFI equipped Mustang GT and has tuned 7 second cars.

Give him a call and tell him Jay from Connecticut sent you.

914.478.1727

91tpi-zf

I would start by taking 2% out of the entire map. Keep doing this until you are comfortable with the 02 readings. It sounds as though you are very rich so you could take out more the first try. I wouldn't go any more than 5% though. You could also reduce the fuel pressure, although I usually determine how much pressure I want to run and tune the program to match this. If you notice, when you go into closed loop the ECM will never take out more than 5.5% fuel at idle. This is due to the nature of the system. Once the rpm's increase the ECM will pull more fuel out but only 5.5% max at idle. You always want the base program a little rich so the computer is pulling fuel out rather than having to add fuel. That way, if the 02 ever fails you will be a little rich, but it will not hurt the motor like running lean will.

P.S. Some people will lead you to believe that it is near impossible to tune a car yourself. This is not the case. There is a lot of trial and error in these modified EFI cars. All of the programs I have gotten in the mail have never been that close. Every one I have gotten has been too rich. Let me know if I can help any more.

Chad

88L98

i dont know if DFI is anything like prom burning, but i would assume that you can change your target Air/Fuel Ratios at part throttle, idle, and WOT. I do mine like this. Also add a little bit more timing or try changing the constant value of your injectors to a lower lb rating.

HighHopes85

IF it uses a MAP sensor and IF it uses BLM's to show rich/lean conditions...

If your BLM is at 108 and nominal is at 128, use (108/128)=.84375. Multiply that by the volumetric efficiency at a certain MAP IF you have a table for that. That is what works on stock speed density systems, but I assume DFI is another ballfield, so this is probably useless. -Matt-

88L98

on tuning, i always do mine like this. i set the target air fuel ratio to rich and hook up a scanner and go out for a test drive. i log all the information and come back and if i have no knock counts, i add a little timming and lean the mixture out just a tad bit, and go for another drive. do this repeatedly until you either start getting knock counts or start to feel power loss.

JOHNL

Why don't You take some of that money and bring it to a shop? just playing.

snaketr

Bill, call Dan. I know others have said crazy stuff about mail order programs or whatever. You do not want to hurt you motor. Dan is the man on the DFI's. Mark Hamil just left DFI and he would have told you to use Dan. He has an customers 89 out there right now that has a 355 naturally aspirated and no n.o.s and it turns in the 10.90's. Before you do anything at least give him a call first. His # is 804-598-7727 or you can call me at 800-962-9632x256 my name is Justin.

88L98

if i was you, id follow snaketrs advice. all of my advice is about normal prom burning, so im just trying to give you an idea of how i do mine. im not sure how DFI works completely but it cant be *too* different. btw, what kinda DFI is it