Hi, when switching over to the distributer, i set the rotor phasing to 25,btdc. However I seem to be getting a misfire at about 2000 rpm on the highway, and adding fuel is not fixing the problem. So I was thinking, i do run 45 degrees timing at cruise at this rpm and now that means im 20 degrees out, and maybe i am getting spark scatter, causing the misfire? WHat do you guys think? SHould i move the phasing or reduce the timing?
rotor phasing?
- Thread starter norbs
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Well the miss is gone as long as i use my gen 6 batch fire 
, so the miss is something else, I am thinking injector target timing is not set right, even though i followed what it should be set. I will have to try the gen 7 in batch fire mode and see what happens!
I also can report that running the lm-1 in closed loop correction on the gen 6 is a pleasure to drive....nice solid a/f cruising numbers with WOT correction.
, so the miss is something else, I am thinking injector target timing is not set right, even though i followed what it should be set. I will have to try the gen 7 in batch fire mode and see what happens!I also can report that running the lm-1 in closed loop correction on the gen 6 is a pleasure to drive....nice solid a/f cruising numbers with WOT correction.
ski_dwn_it
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- May 3, 2005
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- 96
Norbs I had to run 20* offset in my gen7. phase the rotor at 25* and then set timing accordingly with the crank trigger to match the ECMs locked timing.
I was concerned where it would be at with full timing, so I cranked the motor over by hand to see where it was at with relation to the post at say 37-38* its still VERY much inline with the #1 post on the distributor.
Rotor doesn't change much position between 25* and 38*.
I was concerned where it would be at with full timing, so I cranked the motor over by hand to see where it was at with relation to the post at say 37-38* its still VERY much inline with the #1 post on the distributor.
Rotor doesn't change much position between 25* and 38*.
Interesting idea, but putting the offset to 20* only means that your timing can never drop below 20* which is fine, as long as you don;t use NOS retards. By putting the crank sensor to show the same as your locked timing map, means its sitting at 20*btdc in reality. I'm not sure how critical the phasing is for cruise timing, as you say yours run;s fine. I may have another problem as i went back to gen 6 and the misfire is gone with the same distributor phasing, but now have run into other problems, 4000 rpm rev limit.
I was thinking its my injector target timing, but i have run the gen 7 in batch mode and it still has the same cruise misfire/stumble.
I was thinking its my injector target timing, but i have run the gen 7 in batch mode and it still has the same cruise misfire/stumble.
ski_dwn_it
Member
- Joined
- May 3, 2005
- Messages
- 96
Norbs,
I never really did understand what offsetting that 20* did for me. When I originally tried to run the trigger I could not get the timing marks in sequence with the laptop. I would run out of adjustment on the trigger before I could get it to the timing I desired. I called craig and he instructed me to use the offset, when I did everything fell into the range that I needed it to. However I can't get in my head what it all means..........its worked since, but suppose I should completely understand what it truely means.....
Care to try to explain it to me. Might help you with what your struggling with too. Sometimes when I explain something to others it deepens my own understanding of the topic.....
Guess I always thought of the offset as nothing more than if I had taken the crank sensor itself and rotated its physical location another 20* with respect to the wheel??? Is that right? Or am I oversimplifying?
Also you mention injector target timing.....I left this as default value and how does one go about figuring out the correct target timing. I am running ford svo 30# injectors????
Don't mean to high-jack your thread with questions of my own - you have some interesting topics happening though.
Regards,
I never really did understand what offsetting that 20* did for me. When I originally tried to run the trigger I could not get the timing marks in sequence with the laptop. I would run out of adjustment on the trigger before I could get it to the timing I desired. I called craig and he instructed me to use the offset, when I did everything fell into the range that I needed it to. However I can't get in my head what it all means..........its worked since, but suppose I should completely understand what it truely means.....
Care to try to explain it to me. Might help you with what your struggling with too. Sometimes when I explain something to others it deepens my own understanding of the topic.....
Guess I always thought of the offset as nothing more than if I had taken the crank sensor itself and rotated its physical location another 20* with respect to the wheel??? Is that right? Or am I oversimplifying?
Also you mention injector target timing.....I left this as default value and how does one go about figuring out the correct target timing. I am running ford svo 30# injectors????
Don't mean to high-jack your thread with questions of my own - you have some interesting topics happening though.
Regards,
Well your correct about the crank sensor with your idea's. Your sensor was so far off thats why you couldn;t read it without the offset in there.
AS for target timing, its the time the injector fires based on the intake valve opening events. According to the help section you don;t want to inject fuel as the valve is opening, but after the valve is closed, or mixture problems will result on cruise . THe valve on the intake stroke closes at 540 bdc + 30-50 degrees depending your cam timing card intake closing point (ABDC), so the number to put in the target timing chart is 540 + the cam card number as mentioned above.
However, i have found it runs leaner the higher this number is. This number has a huge efect on how enginer runs, so becareful with it. Your whole ve map will be out to lunch. Not sure why you would want to fire fuel onto a closed valve, makes no sense to me, but this is what the instructions are telling me. Maybe Craig can explain it better
AS for target timing, its the time the injector fires based on the intake valve opening events. According to the help section you don;t want to inject fuel as the valve is opening, but after the valve is closed, or mixture problems will result on cruise . THe valve on the intake stroke closes at 540 bdc + 30-50 degrees depending your cam timing card intake closing point (ABDC), so the number to put in the target timing chart is 540 + the cam card number as mentioned above.
However, i have found it runs leaner the higher this number is. This number has a huge efect on how enginer runs, so becareful with it. Your whole ve map will be out to lunch. Not sure why you would want to fire fuel onto a closed valve, makes no sense to me, but this is what the instructions are telling me. Maybe Craig can explain it better
The DFI 7 help screen instructions are contrary to the sample PNP programs that come with DFI. I’ve gone through all the sample programs and with the exception of one turbo program they are all set to 360 degrees across the map. At 360 degrees the intake cycle is beginning, I can’t imagine any cam would have just finished closing the intake at that point. Additionally most cams that have any overlap would still have the exhaust valve open at this point so you risk losing your fuel to exhaust scavenging I would think. I wish we could get some clarification on this.
