quote:

Originally posted by Bucky:

quote:

Originally posted by Mike Beck:

quote:

Originally posted by Bucky:
I was thinking of doing the same with the injectors and am glad to have some affirmation.
Cam sensor on the belt drive and toothed wheel on the crank with a hall effect sensor on both.

I'm pretty sure I was ignoring the too rich condition as the fuel consumption was high and the catch can was getting alky every run. But I was believing o2 sensor instead.

The friend I have that tested his Holley Throttle body system on his super comp dragster today made one partial pass, then one full pass, 8.85 or so. On the stop of course. It's not supposed to be that easy! He is on race gas.

Dave is 100% correct up there. Too lean OR too rich will both show cold pipes.

Which trigger wheel are you using on the crank?

Is your friend running port fuel injection or a throttle body setup with the injectors up top? If running port fuel injection, Alpha-N or Speed Density?

Throttle body, and not sure. But he used a stop under the blades last night, and right out of the box that thing was flat lined and smooth on the stop. That makes me think it is just using the map sensor for the table. But I'm still a little ignorant on this subject.

quote:

Originally posted by Magnethead:

quote:

Originally posted by Bucky:

quote:

Originally posted by Mike Beck:

quote:

Originally posted by Bucky:
I was thinking of doing the same with the injectors and am glad to have some affirmation.
Cam sensor on the belt drive and toothed wheel on the crank with a hall effect sensor on both.

I'm pretty sure I was ignoring the too rich condition as the fuel consumption was high and the catch can was getting alky every run. But I was believing o2 sensor instead.

The friend I have that tested his Holley Throttle body system on his super comp dragster today made one partial pass, then one full pass, 8.85 or so. On the stop of course. It's not supposed to be that easy! He is on race gas.

Dave is 100% correct up there. Too lean OR too rich will both show cold pipes.

Which trigger wheel are you using on the crank?

Is your friend running port fuel injection or a throttle body setup with the injectors up top? If running port fuel injection, Alpha-N or Speed Density?

Throttle body, and not sure. But he used a stop under the blades last night, and right out of the box that thing was flat lined and smooth on the stop. That makes me think it is just using the map sensor for the table. But I'm still a little ignorant on this subject.

A blade stop on EFI? I'm surprised that would even work...at WOT the EFI wants to dump in 100% rated fueling, would go dead fat with the blade stop closed (same ROT as MFI + blade stop). Maybe it's different with TBI instead of MPI. MPI it's best to use an inline stop.

quote:

Originally posted by Magnethead:

quote:

Originally posted by Bucky:

quote:

Originally posted by Mike Beck:

quote:

Originally posted by Bucky:
I was thinking of doing the same with the injectors and am glad to have some affirmation.
Cam sensor on the belt drive and toothed wheel on the crank with a hall effect sensor on both.

I'm pretty sure I was ignoring the too rich condition as the fuel consumption was high and the catch can was getting alky every run. But I was believing o2 sensor instead.

The friend I have that tested his Holley Throttle body system on his super comp dragster today made one partial pass, then one full pass, 8.85 or so. On the stop of course. It's not supposed to be that easy! He is on race gas.

Dave is 100% correct up there. Too lean OR too rich will both show cold pipes.

Which trigger wheel are you using on the crank?

Is your friend running port fuel injection or a throttle body setup with the injectors up top? If running port fuel injection, Alpha-N or Speed Density?

Throttle body, and not sure. But he used a stop under the blades last night, and right out of the box that thing was flat lined and smooth on the stop. That makes me think it is just using the map sensor for the table. But I'm still a little ignorant on this subject.

A blade stop on EFI? I'm surprised that would even work...at WOT the EFI wants to dump in 100% rated fueling, would go dead fat with the blade stop closed (same ROT as MFI + blade stop). Maybe it's different with TBI instead of MPI. MPI it's best to use an inline stop.

quote:

Originally posted by Bucky:
Maybe Gregg or Mike can answer a curiosity for me: On my old mechanical FI, I could pull the fuel bypass at idle and as you leaned it out, the rpm would climb, and egt's get hotter. I haven't found that sweet spot with the EFI. I lean it and lean it and pretty soon the idle just falls apart and it stops running.

GK - www.MotorSportsInnovations.com
609-265-2110 GKelley@MotorSportsInnovations.com

quote:

Originally posted by Greg Kelley:

quote:

Originally posted by Bucky:
Maybe Gregg or Mike can answer a curiosity for me: On my old mechanical FI, I could pull the fuel bypass at idle and as you leaned it out, the rpm would climb, and egt's get hotter. I haven't found that sweet spot with the EFI. I lean it and lean it and pretty soon the idle just falls apart and it stops running.

I had this with the Bosch 160 injectors. You try to get the pulse width so small - it's like the injector can't do what is commanded.

I now have Billet Atomizers and idle is normal and responds like you said your MFI did.

quote:

Originally posted by Greg Kelley:

quote:

Originally posted by Bucky:
Maybe Gregg or Mike can answer a curiosity for me: On my old mechanical FI, I could pull the fuel bypass at idle and as you leaned it out, the rpm would climb, and egt's get hotter. I haven't found that sweet spot with the EFI. I lean it and lean it and pretty soon the idle just falls apart and it stops running.

I had this with the Bosch 160 injectors. You try to get the pulse width so small - it's like the injector can't do what is commanded.

I now have Billet Atomizers and idle is normal and responds like you said your MFI did.

quote:

Originally posted by Bucky:
Is the Holley 160 a relabled Bosch 160?

quote:

Originally posted by Bucky:
Maybe Gregg or Mike can answer a curiosity for me: On my old mechanical FI, I could pull the fuel bypass at idle and as you leaned it out, the rpm would climb, and egt's get hotter. I haven't found that sweet spot with the EFI. I lean it and lean it and pretty soon the idle just falls apart and it stops running. Never does the rpm climb like I am used to.

I also have one cylinder that is about stone cold during a run. At idle I can pull the plug wire on that one with little effect. I figured I would swap that coil to a different cylinder and see if the cold cylinder follows the move. I also think that I have been pig fat....the egt's show that as well. But the o2 sensor has been showing very lean. I have been pretty sharp at tuning MFI systems in the past. But starting with a problem has me scratching my head a little. Could be plug wire, coil, wiring. I have the coils mounted in this dragster near the block. Maybe they are getting a little warmer than they like. Although I doubt that it's warmer than under a closed hood.
I am not auto tuning, and frankly that's because I don't trust the o2 readings I am getting.
Any other suggestions? I don't get many chances to work on it. So when I do, I like to try everything I can.

quote:

Originally posted by sittin duck:

quote:

Originally posted by Bucky:
Maybe Gregg or Mike can answer a curiosity for me: On my old mechanical FI, I could pull the fuel bypass at idle and as you leaned it out, the rpm would climb, and egt's get hotter. I haven't found that sweet spot with the EFI. I lean it and lean it and pretty soon the idle just falls apart and it stops running. Never does the rpm climb like I am used to.

I also have one cylinder that is about stone cold during a run. At idle I can pull the plug wire on that one with little effect. I figured I would swap that coil to a different cylinder and see if the cold cylinder follows the move. I also think that I have been pig fat....the egt's show that as well. But the o2 sensor has been showing very lean. I have been pretty sharp at tuning MFI systems in the past. But starting with a problem has me scratching my head a little. Could be plug wire, coil, wiring. I have the coils mounted in this dragster near the block. Maybe they are getting a little warmer than they like. Although I doubt that it's warmer than under a closed hood.
I am not auto tuning, and frankly that's because I don't trust the o2 readings I am getting.
Any other suggestions? I don't get many chances to work on it. So when I do, I like to try everything I can.

I have been told and Gregg can probably confirm this, that a O2 sensor reads burnt fuel or exhaust gas not fuel so if raw fuel is going across the sensor it will not read and show lean. Just what I've been told.

quote:

Originally posted by Mike Beck:

quote:

Originally posted by sittin duck:

quote:

Originally posted by Bucky:
Maybe Gregg or Mike can answer a curiosity for me: On my old mechanical FI, I could pull the fuel bypass at idle and as you leaned it out, the rpm would climb, and egt's get hotter. I haven't found that sweet spot with the EFI. I lean it and lean it and pretty soon the idle just falls apart and it stops running. Never does the rpm climb like I am used to.

I also have one cylinder that is about stone cold during a run. At idle I can pull the plug wire on that one with little effect. I figured I would swap that coil to a different cylinder and see if the cold cylinder follows the move. I also think that I have been pig fat....the egt's show that as well. But the o2 sensor has been showing very lean. I have been pretty sharp at tuning MFI systems in the past. But starting with a problem has me scratching my head a little. Could be plug wire, coil, wiring. I have the coils mounted in this dragster near the block. Maybe they are getting a little warmer than they like. Although I doubt that it's warmer than under a closed hood.
I am not auto tuning, and frankly that's because I don't trust the o2 readings I am getting.
Any other suggestions? I don't get many chances to work on it. So when I do, I like to try everything I can.

I have been told and Gregg can probably confirm this, that a O2 sensor reads burnt fuel or exhaust gas not fuel so if raw fuel is going across the sensor it will not read and show lean. Just what I've been told.

Nope. An oxygen sensor, wideband and narrow band, read the difference in oxygen between the air outside the exhaust pipe and what is inside the pipe.

Pull a plug wire off and watch a wideband start showing leaner. Same thing will happen if you pull an injector wire off, no fuel, just air getting pumped through.

This is why exhaust leaks close to or before the wideband sensor will screw with the readings.

quote:

Originally posted by Mike Beck:

quote:

Originally posted by Bucky:
Is the Holley 160 a relabled Bosch 160?

I do not believe it is. Find a flow chart for it and you will see. The Bosch 160's have been around a very long time and have had this non-linear issue since day 1.

quote:

Originally posted by sittin duck:

quote:

Originally posted by Mike Beck:

quote:

Originally posted by sittin duck:

quote:

Originally posted by Bucky:
Maybe Gregg or Mike can answer a curiosity for me: On my old mechanical FI, I could pull the fuel bypass at idle and as you leaned it out, the rpm would climb, and egt's get hotter. I haven't found that sweet spot with the EFI. I lean it and lean it and pretty soon the idle just falls apart and it stops running. Never does the rpm climb like I am used to.

I also have one cylinder that is about stone cold during a run. At idle I can pull the plug wire on that one with little effect. I figured I would swap that coil to a different cylinder and see if the cold cylinder follows the move. I also think that I have been pig fat....the egt's show that as well. But the o2 sensor has been showing very lean. I have been pretty sharp at tuning MFI systems in the past. But starting with a problem has me scratching my head a little. Could be plug wire, coil, wiring. I have the coils mounted in this dragster near the block. Maybe they are getting a little warmer than they like. Although I doubt that it's warmer than under a closed hood.
I am not auto tuning, and frankly that's because I don't trust the o2 readings I am getting.
Any other suggestions? I don't get many chances to work on it. So when I do, I like to try everything I can.

I have been told and Gregg can probably confirm this, that a O2 sensor reads burnt fuel or exhaust gas not fuel so if raw fuel is going across the sensor it will not read and show lean. Just what I've been told.

Nope. An oxygen sensor, wideband and narrow band, read the difference in oxygen between the air outside the exhaust pipe and what is inside the pipe.

Pull a plug wire off and watch a wideband start showing leaner. Same thing will happen if you pull an injector wire off, no fuel, just air getting pumped through.

This is why exhaust leaks close to or before the wideband sensor will screw with the readings.

Ok help me understand you say pull a plug wire off and it will show lean with a wire off no ignition but yet fuel going in that tells me that it would have raw fuel in exhaust so the O2 does not rich ?

quote:

Originally posted by Bucky:
You know, that makes sense. So if you have a sensor on one bank, that bank turns lean looking when you drop one hole on that side.