Tuning my 347 with rear mount turbo

[Dono]

I have to wonder if I ended up with knock off china style injectors. that would make sense to me as to why I'm struggling with this.
They did come from Henson performance, and I trust hi completely, but I'm not absolutely sure if he was sold knock offs without knowing.

 

[Dono]

Ok, I can clearly see the part numbers 108191 and C283A02281

The 108191 part number is the injector I thought I had.
4Point, can you confirm that I use the value file "Ford Racing 60# [M-9593-LU60] v2"? They sure look the same.

 

[4pointslow]

108191 is the Seimens Deka 60 lb injector.
What you need to do next is find the datasheet from them and compare it to the numbers you see in the tune when you add the value file.
Take a stock tune, load the value file and compare the low and high slope numbers to the datasheet numbers.
One of my threads has the injector data sheet posted with errors circled, email me if you have questions about the errors.
Also look and see if the battery comp is changed with those value files.
There may be one more thing that is changed in the tune but I forget what it was.

 

[Dono]

Last night, while re-reading 4pointslows thread about injector sizing, I suddenly had a light bulb go on.

The Siemens deka 60# sct injector data is scaled for a 40 psi return style fuel system. My fuel system is returnless at 65(62?) psi.
Vroomzoomboom has also seen how even having fuel pressure off by a couple of psi really messes with tuning.

What took me so long to clue in to the issue? No idea. My hair is blonde? Ok, its getting more grey than blonde. Seniors moment?
I'm in luck though, I have a guy far smarter than myself holding my hand and teaching me.

The plan is to re-scale the ford racing Lu60v2 injector data that sct provided from the 40psi fuel pressure to the 62psi pressure I have.
I will have to experiment a bit, and try getting an accurate fuel pressure reading as returnless data all points at using 65psi, while I'm pretty sure my truck is supposed to be 62psi. will 3psi make a difference? Not sure, as I'm sure the will be no issue tuning the maf curve either way.

I sure wish I had brought that sct dongle with me. I am out of town with some free time in the hotel tonight, and would love to be comparing value files and doing some math to make my sophisticated wild assed guesses on the injector scaling and have a tune built and ready to try tomorrow.

 

[CDW6212R]

Very good, you have a good path to go at now. That should help.

 

[vroomzoomboom]

i have a thought, not sure it would work. could turn my laptop on, and you can log into it remotely and take a look. or would you need your tune for it?

 

[Dono]

It could work, but I'll be home tomorrow. its 11:00 in your time zone.
Thanks for the offer Tim, I know you need to get up and moving early. that, and cut/paste thru teamviewer is a pain in the arse.

This can wait a day, lol.

 

[4pointslow]

You should try to get a quality Snap On Fuel pressure gauge and see what pressure you really have and then use that in the formula for compensation.
I looked up the fuel pressure spec for your truck and found a useless answer, it says 30-65
LOL. That's bullcrap.

 

[Dono]

Lol, so they are saying to push the Schrader valve, and if gas spurts out its all good. Lol

 

[CDW6212R]

That's a good idea to verify the accurate pressure, it will help the tune to be better.

My 99 used to run about 60-62psi when I got it, throwing a CEL rarely. I kept checking it from knowing the lean code was often the intake o-ring gaskets. The SOHC ran great 99% of the time, then after good year I got a hiccup at high speed and the CEL again. The next time I checked the fuel pressure, it was around 58psi, in park at any rpm. I pulled the tank and found the pump rubber hose barely split at one hose clamp. The PCM was detecting the slight pressure loss, the lean condition. A few psi can make a difference, I think close to 65psi is the intended level(for the PCM programming).

 

[Dono]

I just created a scaled 62pis injector file and a 65psi injector file.
They are loaded in my tuner.

I am comparing my scaling against generic 60's at 39psi and generics at the 65psi.
The break point in my scaling looks odd. Lets see what happens.

I'll try them tomorrow.

 

[Dono]

Ok, coming along here.
For some reason, when I would add the value file of the lu60v2's to my tune, the minimum pulse width would actually move over 1 decimal place. Looking back at it, thats huge. No wonder my truck would run so rich with these injectors, minimum pulse width was dumping all kinds of fuel in to the motor. 4pointslow pointed out that that value needs to stay at whatever the factory tune has. Ah, ok I say, that makes perfect sense.

I scaled the breakpoint, high slope, and low slope using the scaling formula that is in 4pointslows injector thread. I scaled them at 62psi. Have I checked my fuel pressure? Nope. I can always re-scale again. On first check without driving, this works great.

Current working injector scaling.

Here's what the injectors for the lu60v2's look when I import the value file in to it. Notice the deciimal place on the minimum. No wonder I couldn't tune the maf curve, lol.

Why does that value file change minimum pulse width so drastically? No idea.

Thanks for the help 4pointslow!

Now back to moving my maf sensor from under my truck to just before the throttle body, where it probably should be. More pics to come.

 

[Dono]

I haven't gone for a drive yet, but initial log looks good. The maf numbers have a bit of a ripple, but I think they are pretty good.
The honey comb might be more trick than actually straightening the , but what the heck.

I was worried about the pcv air intake port causing turbulence just after the maf, so I ground the fitting down. Its so close to the maf, I'm not sure if the maf is actually metering the pcv air, but I did the best I could with the limited space I had.

I'll need to re-scale the maf slightly with the injector data being corrected, and the maf moved. I'm happy with the results so far.

 

[4pointslow]

Looks good!
Nice work!
Make sure that honeycomb stays where you put it. You don't want that going into the throttle plate and holding it open.

The minimum pulsewidth could be lowered below stock too if you needed to.
The symptom that could happen if it is too low is the feel of the engine stalling during deceleration, but may not actually stall.
I guess it is kind of used to keep the engine running on decel if that makes sense.

 

[Dono]

yea, that honeycomb thing fits super tight. Thats also why I actually half installed it in the pipe before the maf pipe. Even if it does start to come out of the pipe its in, there's no way it will get started in the next pipe. I guess even if it did, it would get stopped by the maf. Thanks for yet another tip on that minimum pulse width. It slowly helps me understand whats going on, and why something is in the tune.

 

[Dono]

I'm getting closer. I still get an exhaust smell in the truck with the roof open sometimes, but my eye's don't burn and water anymore. That's a good thing. I can work on slight modifications of exhaust pipe placement and see what works better.

Tim came by last weekend, and showed off without even knowing it. As he was leaving, he jumped in his truck, and it started right up. Imagine that? I was/probably am still struggling with that. I was ready to try different injectors, thinking I must have one leaking.

I found that playing with the cold start fuel table really makes a difference on where the crank fuel pulse width needs to be. Makes sense, screw with one thing and you throw other things off. Laws of nature. I hope I finally nailed it though. Today it actually started every time without having to touch the gas. For whatever reason, my combination is way more finicky about starting (or adjusting for starting) than I think is normal so a vehicle that has had the crap modified out of it.

Anyway, I just might have found the magic. I'm actually pretty excited about it. One of my goals has been to make this truck completely drive-able with no quirks (other than the fact it has a unmistakable sound to it, in the cab it sounds pretty quiet).

I'm still playing with timing as I want to just see the J&S sensor activating slightly when I lean on the gas. This tells me that its probably only modifying the timing on a couple of cylinders, which means best power. Pulls super hard from 3000rpm and up.
I have no warning from the sensor at all below 3000 rpm, so I'm slowly adding at 2500 and 3000rpm (under load with at least 0 vacuum so the brain is turned on). This tells me to add timing slowly. Its a process as I'm trying to get as close to the raggedy edge as possible.

 

[vroomzoomboom]

for what ever reason, we have opposite problems. yours is warm start. mine is cold start. i have a slight surge when its cold for about the first min or so. think i am going to have to live with it.

 

[Dono]

Here's my first thought, but it would probably only affect the first 15 seconds.

I know your idle integrator is set correctly, so that's not it.
Maybe the base fuel table cold is adding too much, or too little fuel from 70 to 100 degrees at low (idle) load? We would have to play around with it and see if anything makes a difference.

 

[Dono]

Iv'e been struggling with taking out the thrust bearing in my motor, and am looking at all possibilities.
What might be happening is that there is to much trans fluid line pressure pushing the torque converter in to the flex plate, and in turn the pressure pushes the crank hard in to the bearing, wiping it out.

This includes fixing up some trans cooler lines that were cut, and returning them to factory. There was a couple of tight L connectors that might have been restricting flow. I also have a new torque converter with a billet front cover on it to take the possibility of ballooning out of the picture.

This led me down a road also as to the need to check trans line pressure. I obviously can't do this until the motor is back in, but I still want to see if I can reduce the pressure using tuning. Decipha wrote this article (Thanks Decipha!) Transmission / EFIDynoTuning and it specifically talks about trans line pressure being affected by the torque table.
Here's a quote from Decipha that made me take a second look:

"Dynamic TV pressure is calculated by engine torque, the ecu uses the current airmass from the MAF Sensor to calculate engine torque. That value is compared to the engine
torque table FN1615A - Engine Torque Table, which is scaled by Load and RPM, if the actual torque is less than this table then you get excess pressure,
If the actual torque is greater than this table then you get less pressure. This table must be manually dialed in by the tuner. "

Now, Decipha does not tune SCT, but the ecm still has the same programming, no matter what method you use to tune it. This made me look in my current tune in the SCT Pro Racer Package. There are some area's I had not really looked at, and had purchased a tune from Don Lasota to see if he could help me with some issues.

Here's the description of the Torque Table in the SCT software:

The following are 3 screen shots of the factory torque table, what Don Lasota has mine set to, and the 3rd is the torque table I am thinking of starting with when the motor goes back in.

Factory

Don Lasota Settings

My "Best Guess" wild arsed guess settings:

@4pointslow is willing to put the effort in to helping me with this and let me know with some fact (Rather than my guessing) if I'm on the right track, or lost in some field. There is really no way to completely understand some of this stuff as a pure hobbyist. Taking out these thrust bearings is getting really expensive, so its worth looking at everything.

 

[2000StreetRod]

Interesting. As you have determined, PCM calculated load is an important variable. That is the reason I refused to alter the MAF sensor function to achieve the desired AFR.