Tuning my 347 with rear mount turbo

[2000StreetRod]

spark adders

I made some good progress. . . I'm still seeing more timing that I am commanding in the borderline spark table. I'm not hearing any detonation, and at the top end I'm down to 13.75 degree's. Still at 3500rpm and 2 lbs boost I'm seeing 19 degrees. Not horrible, but I better learn my spark tables. . .

According to Advantage Help, Ford Tuning, Spark:
"In addition you will want to make sure you set SPK_ADJ_FOR_EMISSIONS and SPARK_ADJ_FOR_COMBUSTION_NOISE to all zeros. You cannot do this on a supercharged engine. You cannot put MBT spark everywhere and expect the air temp sensor to be able to compensate for it. In these cases you will need to lower the BORDERLINE_KNOCK_TABLE to compensate for the spark requirements.

In this version of spark there are two other parameters of interest, SPARK_GLOBAL_ADDER and SPARK_GLOBAL MULTIPLIER. These values allow you to override the above calculations and just add in spark to the final calculation. It does not check it against the base table; it just adds it to the final amount. The SPARK_GLOBAL MULTIPLIER multiplies the final spark value by whatever that multiplier is."

I don't know if all of the above apply for your strategy but I suggest you check them.

By the way, for your posted Borderline Knock Table at 3500 rpm the spark is 39 for load = .3 and 14 for load = .4. That means if the load is .35 the BKT spark will be 26.5 {[(39-14)/2]+14}. What was your logged load when your spark was 19 deg at 3500 rpm and 2 psi boost?

 

[Dono]

Boost: 1.97
Load: 0.778
spark: 19.25
rpm: 3870
Spark Source: 2 (borderline knock table)

I'm missing something.

oops...Something I did last night puts my chin in to the steering wheel when I start to step on the gas. lol.
I'm not going to bother analyzing it, but obviously its spark related. I'll step back a version and make some less aggressive changes.

 

[Dono]

After a bit of frustration, I found that I obviously made an error in my maf transfer calculations yesterday.

I returned the maf xfer table to where the night started last night, and lowered my max allowed spark table from where I started yesterday. I guess that's just how learning goes....

I also upped my a bit more. Detonation.....
Analog 1 is the boost, and analog 2 is the a/f ratio. The rest are self explanatory. Obviously things start to change in a hurry as boost is added.

I pulled timing a few degrees from the offending spot upwards in both rpm and load.

 

[4pointslow]

MAF counts

Did you have a MAF count that was lower, above a maf count that was higher?
I did that to myself once, it feels like the fuel pump just shut off. lol.

 

[Dono]

I did that to myself once, it feels like the fuel pump just shut off. lol.[/QUOTE]

My maf curve showed small bump. I reversed the maf adjustments from the night before and I was back in business.

I tried lowering my mbt spark table numbers out of curiosity, and it definitely does lower calculated load. And, as it states, has no effect on actual spark (Other than lowering load). I'll be moving the mbt spark numbers back where they were since higher load means more timing retard in my tune. I sure wish I could find the offensive multiplier. I have been up, down, and around the 'spark' tree of my strategy what feels like a million times.

On the way home from last nights WOT, I felt like I was in Stephen Kings 'The Fog'. Coolant spraying on the exhaust. nice.

It turned out to be a quick fix as the coolant supply lines on the coolant tube (On top of the intake manifold) that used to supply coolant to the throttle body are capped off. One of the caps sprung a leak, spraying the area down. Easy fix. You have to know I was feeling some anxiety.

 

[2000StreetRod]

MBT affecting load?

. . . I tried lowering my mbt spark table numbers out of curiosity, and it definitely does lower calculated load. And, as it states, has no effect on actual spark (Other than lowering load). I'll be moving the mbt spark numbers back where they were since higher load means more timing retard in my tune. . .

It surprises me that the MBT spark table alters the load calculation. Is it possible that the MBT spark table is instead just altering the shift points or the torque converter lock? I'll have to research this.

 

[Dono]

I'm sure my load levels wen't down. I don't see why this would happen when I up boost. I plan on having a definitive answer tonight. I'll move the mbt table back to where it was and do a wot run.

 

[4pointslow]

On the way home from last nights WOT, I felt like I was in Stephen Kings 'The Fog'. Coolant spraying on the exhaust. nice.

I would have been crapping my pants, like oh I hope that's not another headgasket!

I would try to find a way to remove the nipples that are capped off and thread the holes and put metal plugs in them. I have found that rubber caps fail often and it is not worth taking the chance overheating and causing more damage.
Of course it is easier to type than do.

 

[2000StreetRod]

calculating load

Don, I remember John and I had a discussion on load some time ago. Here's the definition according to the source code in an earlier strategy:

"Normalized air charge, referred to as load, is a unitless parameter indicating the ratio of the cylinder air charge to the theoretical air charge of a full cylinder at EEC Standard Temperature and Pressure (standard air charge, SARCHG). Using load makes all engines more directly comparable, and allows a similar scaling for all table look-ups. The definition of standard air charge is:

SARCHG = 2.701E-09 * pi * [(B/2)**2] * S lbm/intake stroke

where B = bore in millimeters
S = stroke in millimeters

(2.701E-09 = density of air in lbm per cubic millimeter)"

SARCHG is equivalent to the displacement of the engine. The cylinder air charge is the mass of air measured by the MAF sensor. As I recall the PCM corrects the measured value for the IAT. I looked thru the MBT spark sections of the source code and found no indication that it affects calculated load. When an engine has boost present the measured cylinder air charge can exceed the theoretical air charge so calculated load exceeds 1.0.

The PCM also calculates an inferred load without using the MAF value and compares that to the calculated load. As I recall if the comparison result (difference) is excessive the PCM declares the MAF sensor failed and reverts to the load w/failed MAF table. Its a pain to update that table after changing anything that affects load (i.e. MTF).

Just an unrelated note: With my new laptop running Windows 10, currently I have to reboot with the dongle installed before I can start Advantage. I think that's because it doesn't find the compatible USB driver otherwise.

 

[Dono]

Thanks for the explanation. I have proved you are correct.
I brought my mbt table timing back to where it was (More advance) and did not see a change in the load.
Its interesting that increasing boost did not seem to increase load. With load close to 1, I am scaled for 1.2, so its still not bad at all. Not worth re-scaling.
I'm currently just over 5lbs boost, so I'll be upping it a hair.

Spark currently goes from:
load:.73, spark:14, Boost: .045 RPM:3491
to
load:.78, spark:13, Boost: 4.41 RPM:5450

Its interesting that boost peaks at 4556rpm
load:.92, spark:13, Boost: 5.33

I'm not going to touch the timing till I have bumped up the boost a bit and have the maf dialed in.

I'm very close on the maf transfer (a/f ratio). There is one quick spot where I am out of range (Just under 16:1) just rolling in to boost. I think this is the spot that was giving me aggravation yesterday. I dialed in the maf again tonight, and was conservative in that trouble spot (But brought the a/f about 10% richer), loaded a drive around tune with adaptive learning on, and ran some errands. My chin didn't hit the steering wheel, and my wife didn't bounce off the dash. That's a good thing.

Hopefully tomorrow night will bring another wot pull with a bit more boost.

And....I wasn't hearing a Stephen King tune in my head tonight in a sweet, burnt(ish) smelly fog of coolant. Happy days!

This spring I will pull that heat tube off and tapping those coolant holes for bolts (It will have to come off to fix my oil leak at the lower intake valley anyway). That's a great idea. Thanks 4point!!

Also, my barometer (my wife) keeps telling me how much better my truck is to be in. I guess this is what you get for doing your own tuning and putting the time in to the details.

 

[vroomzoomboom]

Also, my barometer (my wife) keeps telling me how much better my truck is to be in.

which means you'll be driving the honda, and she'll be racing the explorer

 

[2000StreetRod]

MAF AD Counts?

. . . Its interesting that increasing boost did not seem to increase load.

Did your max MAF AD Counts increase when the max boost increased for the same engine speed? If not, then your MAF sensor could be pegged or the restriction to air flow is not allowing the added boost to increase airflow for that engine speed. The max load will not increase unless the max MAF AD Counts increase for a given engine speed. Remember that load is comparable to the adiabatic efficiency of the engine. Increasing the boost may broaden the engine range of max load.

. . . load:.73, spark:14, Boost: .045 RPM:3491
to
load:.78, spark:13, Boost: 4.41 RPM:5450

Its interesting that boost peaks at 4556rpm
load:.92, spark:13, Boost: 5.33 . . .

The total airflow (MAF AD Counts) should continue to increase with engine speed but the max adiabatic efficiency occurs at 4556 rpm.

 

[Dono]

MAF add counts do level off.
Apparently that's common with a turbo application. They actually even drop ever so slightly The MAF is not pegging.
I'll up the boost a hair more and we will have a direct comparison I can post.

 

[Dono]

I have a question on stoich.

Based on a chart JD4242 posted.
http://www.explorerforum.com/forums/showpost.php?p=3507737&postcount=624

Most (Say 90%) gasoline has close to 10% ethanol. I don't even know if we can get gas here without ethanol.
Wouldn't it be better to tune slightly richer? Maybe 14.3:1 ?
I mean, stoich is supposed to be max efficiency mixture of the fuel, correct?

 

[2000StreetRod]

ethanol fuel economy

Our local pumps are marked "may contain up to 10% ethanol". So the optimum fuel economy and emissions reduction can vary accordingly. With the ethanol subsidies that exist in the US the ethanol content probably stays near the maximum of 10% so 14.1:1 would probably result in better fuel economy. I can still purchase ethanol free premium fuel so I haven't changed the stoichiometric ratio in my tune. As little as I drive my Sport I really don't care about fuel economy.

 

[4pointslow]

Stoich

Greg Banish says to shoot for 14.4, since it is kind of in the middle of 14.13 and 14.7 and most people wont be testing their fuel for ethanol content. That information is off his $250.00 DVD that can be purchased from summit.

If you want to be exact then you need to measure the ethanol content, at every fill up. JD posted a picture of an ethanol test kit on his ranger thread.
There are also ethanol sensors, Innovate has one and you can even get a gauge for it.

I have 14.4 entered into my tune for stoich.

 

[Dono]

And, with a few key strokes.....stoich is now 14.4

Have I said how awesome it is to be able to make your own changes any time you want?

 

[Dono]

While I wait for parts (My back is extremely unhappy with me, so its not the end of the world right now), I have been thinking about tuning some more. I know...seems like I have too much time on my hands.

Anyway, Lean tip in when you step on the throttle quickly.....How do you adjust it?

I was seeing it in my tune, and I'm pretty sure anyone with a power adder see's it. Problem is, I don't see where it can be adjusted.

My parts are going to be slower coming than anticipated. I think flowtech inductions is running a bit behind at the moment. Its probably better to purchase from the guy that is really busy rather than the guy that isn't. He's probably busy for a reason.

 

[4pointslow]

Just the tip in.....

The load with failed maf table is supposed to help with lean throttle tip in problems on certain PCM's so you could try that.

I had lean tip in problems until I added the water/methanol, then it went away.
I use -25 degree Rainx, it is 40% methanol. I did have to lean out the air/fuel mixture a tad during spray.

 

[Dono]

Ah, thanks!
Tim's been a bit pre-occupied with another project. We need to get back on his tuning.
Step testing is done, but there is still wot to go. Tim did mash the throttle once and Evil just bogged and back fired.
I think a true wot is in order so that I get some usable log to see whats going on. Im betting it was a lean backfire. Boost comes on so fast with that SC of his, I can see having to richen the maf curve an awful lot.