The only way to do it would be to not run a spacer. And have the black things "seal" against the head. Which they wouldn't.

But hey, some people like being on fire.

 

Yeah. I just finished removing them. Easy once you figure out how. My friend somehow got his in with them on, don't know how. Didn't think it sounded right that he did, but the car is running well. He said they stuck up until he bolted the fuel rail on then they squished into place. We will see how they are long term on his car.

 

Right, got the new fuel injectors in (along with some maintenance and a vented quarter window). Having some problems now though. The AFRs are all over the place, even with a stable RPM and MAP. This is with EGO correction off (I was hoping it was something silly like that). I had rock solid idle and such before swapping the injectors. All I can think is something is installed wrong or I am just a dunce and missed an important setting. Too tired to troubleshoot it right now, I will poke at it in the morning.

For peace of mind though, could you guys tell me if I have the dead times set right for GT500 injectors? (Used the numbers on the flow force site).



Here is the variance in AFR I am seeing, it was stalling out instead of returning to idle as well, hence the high idle (just turned off PWM idle control and opened up the idle screw. Since it idled fine until it warmed up, then stalled out at an intersection, woops). I will go through the changes made with a fine toothed comb tomorrow. And yes, I changed the required fuel.

 

Post tune

 

The VE table is a mess since once it warmed up it became almost undriveable and I had stupidly already gotten 5 miles from home. I just indiscriminately threw fuel at it until it ran, sortof.

 

Got the new battery in and got some tuning done now that I can actually start the car reliably. Old battery could only do 102A at 80F.

Heavy cruise and higher rpm/map tuned up nicely. I am still having that problem with idle fluctuation if I am leaner than 12.5, over run will not read anything but full lean on my gauge, even with my 20kpa row set to 70+ on the VE table. Idle requires 70+ to hit the 12.5 it will idle reasonably at.

After lots of thinking and some research, I am 90% positive this is an incorrect dead time setting. I used the numbers on the FlowForce site, but did not buy the GT500 injectors from there. I am pulling data points from my data log of the drive today and am going to try calculating the actual dead time and seeing what happens tomorrow.

 

Overrun is fuel cut....so full lean...

Flow force injectors are GT500 injectors same deadtime.

 

I have fuel cut turned off since I have no TPS. Sorry, I probably shouldn't have called it overrun. Whenever I am in full vacuum it goes full lean, even with 70+ in the VE table still.

And supposedly the are the same dead time. But entering too short of a dead time is the only thing I can thing that will give me all of the symptoms I have. It seems like the injectors are putting in no fuel any time they are around 1.3ms PW. Which is about what I calculate the dead time to be using excel. The intercept ends up being 1.288ms.

The deadtime listed on the flowforce site is 1.12ms at 13.2v.

Also thinking this because in auto tune set the VE cells the same from 30kpa to 50kpa.

Once the PW is above 1.42ms or so, everything behaves ok.

Idle at anything above 12.5AFR acts like it has random lean misfires. But I know of now reason an engine would misfire under no load at

 

Spark cut then?

 

Shouldn't be. Don't have any spark cut of any sort turned on anywhere. I even have the idle control valve turned off now and just used the idle screw to set it to 1500rpm or so (lower than that, it tries to stall. Probably from not enough fuel due to too short a dead time). I set the dead time to 1.288ms, so we will see what happens when I try to drive to work tomorrow.

 

EDIT: below PW numbers are wrong. I made an ASSumption that the PW1 was the pulsewidth it was actually outputing, rather than SeqPW. I need to reread the manual. It was too long ago that I read the whole thjng.

Found the thread where everyone was figuring out the dead times from earlier this year. I have all the same idle and high vaccume issues, but with the supposidly correct dead time.

My pulse widths at idle are in the 1.2-1.5ms range. But I am still running the bank injection with two squirts per engine cycle. I am thinking I am running into non linear small pulse width problems. Will these be stable enough to try and use the nonlinear small pulse width tables? Or do Injust need to go full sequential?

The anoying thing is, these dropped right and run perfectly on my friend's car with his FM Link ecu. Maybe I have a bum injector?

 

Yeah, I am just well into the non linear range of these. I wish I had known they wouldn't be happy running semi-sequential on a 1.6.

Calculated deadtime is 1.24ms. Which is what I set it to this morning as a guess.

My (actual) idle pulse width to get 12.5afr or so is 1.54ms. So this means an actual open time of 0.3ms or so.

Guess I get to try and measure the non-liniarity of these and play with the small pulse widths feature on the MS3.

I am still stumped why they idle so nice on my friends 91 with the Link. That thing is a little mystery box though. The instructions tell you how to tune it, but not what is going on under the hood.

 

I looked at your tune and admittedly know very little about 1.6lyfe, which is why I hesitated to comment.
Your idle timing seems high to me for trying to run 14.7:1.
I would change your timing cells so 42kpa and below from 1000rpm and below are 10 degrees. Then I would change 1000rpm to 12 or 1300rpm.

Also your ego correction is off. It sucks that you don't have TPS, but workable.
I was able to idle 14.7 even with the old incorrect dead times, but I let ego correction take over at idle.

 

Also, your lowest rpm column in the VE table seems odd. I actually lugged my car around with the brake and throttle in low gear to tune my 600 rpm column. My 600 rpm values are slightly higher than my 800 rpm values.
I think my pulsewidth is usually in the 1.9 to 2.1 range at idle depending on conditions.
I run a 1.8 NB with ms2 but I run Flow Force injectors, about the only commonality. So may be apples to oranges.

 

where'd you get that curve, doesnt look right at all...

 

The VE table in the tune I posted is all over since I was messing with it.

The idle pulse width on mine is going to be a bit less, then divided by two (no including the dead time) since I am running batch injection with twi squirts per cycle.

I duno, cause that curve isn't what I had set in mine for the dead time. I will check when I get home.

 

I used the charts provided by Injector Dynamics. looking at FF data, yours looks okay.

 

I am also running batch with 2 squirts 'cus ms2.
I just checked a log sitting in traffic on a 70f day. With my coolant around 200f with my AFR at 14.7:1 my pulsewidth is 1.957 and my spark advance is at 10.2* idling around 975 rpm.

 

Yup, I went based on the charts on the FF website. The dead time I am using I measured using that graphical method to find the y intercept.

Huh. Mine are a lot shorter than that. Maybe it is the more advanced timing doing something? I can try turning it down.

 

Well, lowering the advance at idle and playing with the small injector pulse width curve got everything working well enough to make the car driveable, but not great. So I am going ahead and doing the wireing for full sequential.

Grabbed a second fuel injector harness a while ago. It was grimy and nasty.


Cleaned it up and removed all the electrical tape. Turns out the tape gets nasty and brittle after 25+ years... Also, oil and grime had gotten under it and it was just yuck.



The stock splices are a bit odd... Anyway, cut injector connectors 3 and 4 at the splices. Going to use connector 2 for injector 3, and then wire 3 and 4 for their own wires back to the ECU.



Putting a two pin weather proof connector on for injectors 3 and 4.



Harness rewired, cleaned up, rearranged and then re-wrapped with electrical tape.



Getting the harness back in the car was a lot easier than I thought it would be.

And just to make sure I am right, the injectors are connected:
1-A
3-B
4-C
2-D
Right?