[turbosl2]

I was wondering what i should have my load scaling switch set to. I have had it set to 0 as recommended by the dyno tuner. Should i set this to 1? I was just wondering why he said to set to 0 but it seems most boosted tunes i see 1. I also did a compare and it seems that the J4J1 tune is the only CBAZA based tune that has it set to 0 from ford, all the rest are 2.

If i change this will it totaly throw of my tune, AFR, timing...etc?

[Cougar5.0]

Yes.

[turbosl2]

Yes.

Is that a Yes to set it to 1, or is that a yes that it will throw everything off.

[Cougar5.0]

The latter - it could cause issues in your tune if you just change the switch without compensating.

[2Shaker]

I was wondering what i should have my load scaling switch set to. I have had it set to 0 as recommended by the dyno tuner. Should i set this to 1? I was just wondering why he said to set to 0 but it seems most boosted tunes i see 1. I also did a compare and it seems that the J4J1 tune is the only CBAZA based tune that has it set to 0 from ford, all the rest are 2.

If i change this will it totaly throw of my tune, AFR, timing...etc?

Tom, I've done extensive comparisons of logs from my car with your tune, and logs with my tune. The thing that stands out is the difference in load at the same throttle pos, MAF voltage, and RPM. I concluded yesterday that the reason is your load switch setting versus mine. Wes recommends setting it to 1, J4J1 uses 0, and as you know W4H0, U4P0 and T4M0 all have it set to 2. If there is anything that drives me nuts in this whole tuning thing its in the area of load and how to properly set it up with our engine mods.

I used to have my switch set to 0 and I rescaled the load scaling function (aka "Peak Load at Sea Level vs RPM" in BE) and it seemed to work OK. But Wes convinced me that setting it to 1 would take a lot of the guess work out so that's what I have been using lately.

There is no shortage of opinions here on the best way to set up for load:

set the switch to 0
set it to 1
leave it at 2
rescale the tables you are concerned with
rescale the sealevel function

But now that I've actually observed the effect caused by the difference in our 2 tunes I am going to have yet another look at this topic and what's been written.

[Cougar5.0]

When you set it to "1" - do you have to lower FN320A so that you can force OL when you are at lower RPM's where the load limit to force OL can't be reached?

In the fuel tables, do you just live with the fact that you have to set the AFR's to richer at lower load since at lower RPMs you don't have the scaling to get you into the richer loads (when lugging uphill for instance where 65% is max. VE?)

Do you just allow the loads to go off the edge of the table or do you add a "150%" row at the top?

I guess I don't understand what is gained by setting it at "1" - I know the normalizing function is lost which requires adjustment to force open loop & set proper AFR's under "normal" driving conditions when open loop is forced (going up a hill for instance). Seems like added work to me? I'm sure this has greater implications with CBAZA strategies. I still can't understand the advantage - unless the normalizing function is just too difficult to visualize. Position "2" in CBAZA seems to work similar to "0", so this seems like it also takes advantage of the benefits of normalizing the load WRT VE.

[sailorbob]

Setting aside the '0' vs '1' arguments, leaving the 'Percent Load Switch' (aka PRLDSW) set to '2' is not a good idea on a modified engine unless you modify the various aircharge tables to ensure that the 'Inferred Load' value is calculated correctly.

[Cougar5.0]

Setting aside the '0' vs '1' arguments, leaving the 'Percent Load Switch' (aka PRLDSW) set to '2' is not a good idea on a modified engine unless you modify the various aircharge tables to ensure that the 'Inferred Load' value is calculated correctly.

Ahhh, so the max. VE is static and has to be adjusted manually. This makes for a little more work in CBAZA.

Interestingly, engines like mine with PD blowers can indeed use the switch at "1" without losing much resolution since I can hit over 100% load (VE) from 2k on up. Didn't someone point out that the Eaton blown cars use the switch in position "1"?

[turbosl2]

I would like to be educated in this also. I currently have it set to 0. I am not sure if this is related but it seems that when i am going up hills in 6th gear even at higher rpms (2800) the car jumps right to rich. That really bothers be because it seems like it bogs down really bad and the ECU is driving the car toward 11.55 when in all reality the car is still at like -10in vacuum. I would like to have it stay stoich until i am under boost when on the highway. I am not sure if this is even the case with this being 0 or 1 but the main point here is that it seems everyone likes to use 1 and i am using 0, this bothers me. I think the car feels sluggish driving around town and i think its because it is jumping to OL at higher load and dumping alot of fuel. It drives fine but wants to go to the rich side way to soon. In my opinion this should happen at like 1-2psi not at vacuum at all. If i floor the car in 3rd gear at low rpm, maybe around 2200 and would like to accelerate it bogs until its reving to like 4 or 5000 then picks up. I notice everytime that the AFR is 11.55 and this is happinging way to early and choking the motor.

Again, mostly drivabilty issues because at WOT reving high it screams. Maybe with this switch set to 1 things will change idk. I am afaid to attempt because the car was tuned at 0, and i do not want to have to go back and redo everything. I am scared for another reason because what i noticed on the dyno is that just because you change something in tweecer doesnt mean it works correctly. We tried to change spark retard vs ACT and the car for some reason lost like 80hp even though the datalogs said the same timing. The main reason i do not like to touch things is i cant trust that the tweecer will keep my tune the same without a visit to the dyno. Off topic but that is where i am coming from

[Cougar5.0]

You are looking for a "magic bullet" without understanding completely how the system works. If the system is going open loop at the time you suggest, then you should see it in the logs and you can then either 1) adjust the O/L AFR at that load to make it leaner 2) Push out the FN337 curve so that O/L won't be forced until higher RPMs 3) raise the values in FN035 at lower RPMs so the %Load is less and therefore O/L won't happen until a larger load is hit 4) raise the values in FN320A so a larger %Load is needed to force O/L 5) make sure the MAF is correct if the actual AFR is richer than commanded 6) arbitrarily change the load switch to "1" as this will raise the load needed to force O/L significantly since the ECU isn't set up to use this setting. I looked at 6 strategies for CBAZA and not one of them uses PRLDSW at "1", so realize that this "everybody is doing it" is something that has been developed by amateurs as a work around and may not be as refined as what the Ford engineers have done. Now, you could simply change it to "1" and by some stroke of luck your car may run "better" where you have an issue now, but this is no way to tune a car IMHO. Studying datalogs, making adjustments and then seeing the results is a good way to increase your comfort level. You can flip the load switch and see what happens - that's as legitimate an experiment as any. Just be aware of what you are doing so you know where the trouble spots might be - if you don't, you may possibly have, say, pinging where the engine doesn't go O/L and load is too heavy for stoich AFRs. Eyes wide open.

[turbosl2]

You are looking for a "magic bullet" without understanding completely how the system works. If the system is going open loop at the time you suggest, then you should see it in the logs and you can then either 1) adjust the O/L AFR at that load to make it leaner 2) Push out the FN337 curve so that O/L won't be forced until higher RPMs 3) raise the values in FN035 at lower RPMs so the %Load is less and therefore O/L won't happen until a larger load is hit 4) raise the values in FN320A so a larger %Load is needed to force O/L 5) make sure the MAF is correct if the actual AFR is richer than commanded 6) arbitrarily change the load switch to "1" as this will raise the load needed to force O/L significantly since the ECU isn't set up to use this setting. I looked at 6 strategies for CBAZA and not one of them uses PRLDSW at "1", so realize that this "everybody is doing it" is something that has been developed by amateurs as a work around and may not be as refined as what the Ford engineers have done. Now, you could simply change it to "1" and by some stroke of luck your car may run "better" where you have an issue now, but this is no way to tune a car IMHO. Studying datalogs, making adjustments and then seeing the results is a good way to increase your comfort level. You can flip the load switch and see what happens - that's as legitimate an experiment as any. Just be aware of what you are doing so you know where the trouble spots might be - if you don't, you may possibly have, say, pinging where the engine doesn't go O/L and load is too heavy for stoich AFRs. Eyes wide open.

I def wasnt looking for a magic bullet, but it would be nice. I was just tring to understand what the best approach for a blown car was. I am still confused as to why my spark tables are scaled but my fuel tables are not. I just cant understand how this can work correctly because if i am over 100% load my spark tables are defined for greater then 100% but my fuel tables are not, thus from what i understand the engine will try to command what the fuel tables say for the last row. This means that if i hit 101% load the fuel table says 11.5 and the spark is defined to work accordingly. I think this might be the reason my car wants to turn rich so early, mostly because it idles at 30% load so going over 100% is very easy, and i do understand the supercharger adds to the high load, but why would i want the car going to 11.5 after 100% and all the way up. I highly doubt that is the correct approach to tuning. I know i have a lot to learn but why scale the spark and not the fuel, just so i can have 11.5 AFR all the way from 100% load and above. Idk about how most tune but i do not want my car going to 11.5 at 1psi, mostly because i can be at 2200rpm in high gear and roll into the gas, load goes up, AFR shoots to 11.5, engine is choked from the ECU wanting to send the car to OL at 11.5. So when i tune the car with the WB02 i am trying to adjust the MAF for 11.5 to get commanded to equal actual. I am certainly no expert but looking for some good input. Cougar 5.0 you are making some very good points and now i am not sure what the best approch to getting the car to transition to the correct AFR. My fuel tables are all 14.64 then the top right the last 4 cells are 11.5. There is nothing really in between, i see in the stock ecu it transitions as load and rpm go up. Cougar 5.0 i do not want to have to change the load scaling switch to 1. If i can run 0 this would work for me because the car does good at WOT its just the daily driver part that i think sucks. My MAF seems to match the commanded so should i change the commanded and then readjust the MAF. I know this might be a stupid question but in my CBAZA i cannot find FN035

[Cougar5.0]

I'm seeing FN035 in W4HO - it's called "Air - Peak Load at Sea Level vs RPM". If your load switch is set to "0", this should have been scaled way up so that as you get into boost, the Load axis should keep rising until maybe something like 150% @ redline. It doesn't matter if you go over the edge of the table as you noted that it will simply stay at 11.5 AFR. Now, if you are going open loop too soon down low, you can raise the values there - even though you don't see boost on the gauge, you could still be closing in on 100% load. In any case, if it getting more air than stock down low, the load will be higher, and the percent compared to the value in FN035 @ that RPM will be higher as well. You could add like "10" to all the values below 3500 RPM to start with and see what happens. Even if/when you go open loop, you will now be lower down in the fuel table and the commanded AFR will be leaner. Don't worry about the jumps between cells in your table - it looks fine IMO and the ECU calculates values between cells. The key is to get back into the lower rows at the lower RPMS and raising the FN035 values at lower RPMs should allow you to do this. Give it a shot and do a datalog. You should be able to look at your log now and "guess" how much you need to raise the Load cells in FN035 down low.

[turbosl2]

Maybe its the version of tweecer i have, because for some reason i cannot find FN035. I will try this and see what happens.

[Cougar5.0]

I see "Sealevel Load Scaling vs RPM" in CalEdit 1.30B3.

[turbosl2]

Ya mine is not there, i will load my tune in a different version i have on my desktop.

[2Shaker]

Ya mine is not there, i will load my tune in a different version i have on my desktop.

Tom, look again. Its a function, not a table or scalar. Both of the CalEdit versions 1.30 had this. I think I sent you my tune and you can see it is scaled up quite a bit, and I left it that way even though I flipped the scalar from 0 to 1. I think I'm going back to 0.

When you set it to "1" - do you have to lower FN320A so that you can force OL when you are at lower RPM's where the load limit to force OL can't be reached?.

I've not changed in, it is a straight line at .85

In the fuel tables, do you just live with the fact that you have to set the AFR's to richer at lower load since at lower RPMs you don't have the scaling to get you into the richer loads (when lugging uphill for instance where 65% is max. VE?)

I've not looked for that but will.

Do you just allow the loads to go off the edge of the table or do you add a "150%" row at the top?

I have beeen letting them run off the page with the assumption the value it saw last in the table will not change after it runs off the table.

I guess I don't understand what is gained by setting it at "1" - I know the normalizing function is lost which requires adjustment to force open loop & set proper AFR's under "normal" driving conditions when open loop is forced (going up a hill for instance). Seems like added work to me? I'm sure this has greater implications with CBAZA strategies. I still can't understand the advantage - unless the normalizing function is just too difficult to visualize. Position "2" in CBAZA seems to work similar to "0", so this seems like it also takes advantage of the benefits of normalizing the load WRT VE.

When you say the "normalizing" function I assume you are referring to the sealevel load scaling (FN035)?

[Cougar5.0]

When you say the "normalizing" function I assume you are referring to the sealevel load scaling (FN035)?

Yep - that's the one that ensures that maximum Load = 1 at all RPMs - thus it "normalizes" load. This allows the fuel tables to use all available rows at all RPMs. It also lets FN320A force open loop at the same "relative" load at all RPM's.

[Frit]

The Thunderbird SC's with the Eaton's blower run the switch at 1. When I was on the dyno a few months back, the tuner I was working with and I discussed this and he had noticed I had switched my car to 0 and setup FN035. The car seem to run fine but he set it back to 1, and corrected my tables and the car has never run better. In the SC's, he tends to start richening things up at 60% load and you get target AFR at 105%, and thats where it stays even if the car is capable of running 170% load.. the car theoritically hits 100% at 0psi of boost.

The default normalizers for the tables hit 105%. He doesn't change any of them. I know this for sure on the GURE and GSALI cars, but the 94-95 CZAW0 cars that don't have the WOT spark tables, I would assume he cranks up the spark normalizers at least to get the range he needs to dial in spark.

Frit

[turbosl2]

I guess the reason i asked about the 1 or 0 is because i see different combos using different scalars. Can somone explain the difference between 0 and 1 setting, in non software engineering terms. I can tell you that i am still confused as to why i would scale my spark tables up say to 200% load but leave my fuel tables stil lat 89% or 99% and not scale them also. I see many of use leave the fuel tables unscaled and just scale the spark. I cannot see how this allows the car to harness all of its power. If since i have a supercharger, and a larger CID my car idles at like 30-40% load i see my car can jump over 100% load just going up a small hill in 6th gear. This means since my last 2 rows of my fuel table are setup at like 11.55 my car wants to get into OL and 11.5 AFR just from going up a hill. If i were to try to mimic the idea of all the other supercharged cars/trucks i feel that even if it jumps to OL at 2500 rpm it will be tuned to the AFR in the table. The AFR in the table can be 13.1, 12.9 or any other arbitrary number and does not have to be 11.5. If i leave the fuel table scaled as stock and just jump the spark up, it seems like i am shooting myself in the foot. The car will want to jump OL right when it hits the end of the fuel table and mostly want to hold the values in the upper right of the table, which usually are very rich because the same values are used from 89% load all the way to infinity (200% load or above). So when i attemp to accelerate and load goes up, spark is scaled but the fuel table is still off the chart using its last cells. So basically i have less spark since its scaled up higher, and rich AFR with this method IF i am not making since or confused let me know. I would think keeping it in CL longer so it targets 14.7 until a certain point then jumps to 11.5 is a bad method. Most engines like it a tad rich, such as GM motors seem to make awesome power at like 13.0AFR. I also do not see why have it stay stoich up to a higher point then all of a suden jump to a very rich condiiton. Where i can do what ford attempted to do and transition it off on fuel and spark. Also on the lightning maps that i posted in the other thread i did not post when it jumps ot OL. it jumps to OL at .75 then .68...etc. This is ok since the OL AFR numbers are not very rich and are around 12s-13s until the higher RPMS. I think this attempt is better because it does not use the 02 sensors to get to the target AFR, and the target AFR is not the last few cells because the fuel table is scaled to below 100% while spark is not. Just thinking out loud on how ford spent countless hours settiing up the vehicles to make not only WOT power but all throughout the range

[Cougar5.0]

The spark and fuel tables do not have the same scaling since FN035 scales the load the fuel tables use. It's simple division Load/FN035 = %Load! So if you are at 85% load @ 3000 RPM and FN035 has 120% at 3000 RPM, then %Load = 85/120 or ~71%. So, if you used this scaling, you would be commanding an AFR of about 11.9:1 assuming your engine goes open loop @ this load. My open loop fuel table is 13:1 at this load - so that is what I'd see since I have FN320A set to go open loop @ ~68% @ normal operating temp. (~180F).

You people think tuning a centri is difficult, you should try tuning a KB that can see any load from 0 - 150% from 2200 RPM to redline. It's actually quite simple if you spend a few minutes looking at the logs and figuring out where it's looking in the table, then adjust something.

[cgrey8]

...I can tell you that i am still confused as to why i would scale my spark tables up say to 200% load but leave my fuel tables stil lat 89% or 99% and not scale them also...

Load is a reflection of the instantaneous volumetric efficiency of the engine. VE is nothing more than how much air was pumped through the motor vs what the theoretical max is at atmospheric pressure (i.e. the displacement). In the case of a supercharger, you are dealing with pressures above atmospheric so you can see VEs higher than 100%...a lot higher in many cases.

Load% is an indication of instantaneous engine capacity. You want the scaling function to reflect the engine's absolute max, best-case scenario at WOT and associate those Loads to Load% = 100%. With Load% scaled properly, it's an indication of what % of your motor you are at assuming you can only get 100% of your motor's capacity based on whatever you scaled 100% to mean. I understand the relationship between Load and Load%, but I can't say I fully understand why Ford thought this was a good idea. But for some reason, Ford thought Fuel delivery should be based on the % of engine potential, not based on VE. So they invented Load% and it has forever confused engine tuners since.

Now what the 0 or 1 scalar does is decide whether Load% = Load or if Load% is used to reflect the instantaneous engine capacity. Some have Load% calculated out and rescale FN035 so whatever the max output of their motor is at any given RPM will result in a value around Load% = 100%. Others set Load% = Load so they can scale their Fuel tables to look exactly like their Spark tables and only have to think and datalog one Load, not two. I don't think either approach is right or wrong...just different ways of viewing and dealing with the same information with some arguable benefits. But bottom line is both camps of thought get boosted applications to work safely. So I don't think there is a clear-cut winner, but rather personal preference. And that being said, I usually tell people that have a hard time with the concept to set Load% = Load and keep it simple. As the concept marinates with you OR you see some fuel control problem you can't tune out using Load% = Load, then consider changing it. But that's just me. And also keep in mind that I have never tuned a boosted application, so take what I say on this subject with a grain of salt.

[Cougar5.0]

You can't access the top cells in the table without the Load Scaling function active. Thus the engine would run leaner when you are WOT & lower RPM's (A9L) since "full" load (VE) might only be 70% @ say 2500 RPM. Then if you richen the 70% cell like turbosl2 has, when you are at higher RPMs, 70% load is easier to reach, so now you might be too rich. It looks easier for CBAZA people to adapt to this situation though as their fuel table has RPM in the x-axis in the "stabilized" table.

You also need to realize that the straight-line 85% %Load to go open loop in FN320A will have to be changed if you switch to "1" - in order to be able to go O/L based on load at lower RPM's you will have to lower this to like 50%. But then you will go O/L too easily at higher RPM's where 50% can be reached while cruising!!!

Implying that changing it to "1" makes it "simpler" is simply not true - you end up having to make MORE adjustments - and you can't get FN320A to properly trigger O/L based on load afterwards.

[cgrey8]

...You can't access the top cells in the table without the Load Scaling function active. Thus the engine would run leaner when you are WOT & lower RPM's (A9L) since "full" load (VE) might only be 70% @ say 2500 RPM. Then if you richen the 70% cell like turbosl2 has, when you are at higher RPMs 70% load is easier to reach, so now you might be too rich...

I agree that what your saying will happen. You are right you can never get into the top portion of the fuel table while at low RPMs with Load%=Load, I argue that you don't really need to be that high in the fuel table at lower RPMs where Load can't get as high. Less Load is more tolerant of a leaner mix...and by leaner I mean 13:1 as opposed to 11:1. Just because the motor may be at 100% capacity (i.e. 100% Load%) for that RPM doesn't mean that it needs to run the same AFR as it does at 100% capacity at higher RPMs where Load is much greater. At least IMO. I could be wrong.

...It looks easier for CBAZA people to adapt to this situation though as their fuel table has RPM in the x-axis in the "stabilized" table...

That, in my opinion, is GUFx defs biggest downfalls...not having the fuel table associated to RPM/Load, but rather ECT/Load.

...Implying that changing it to "1" makes it "simpler" is simply not true - you end up having to make MORE adjustments - and you can't get FN320A to properly trigger O/L based on load afterwards.

Ahh, you got me there. You are right, it isn't as simple as just flipping the switch and you are done. You do have to rescale the Fuel table and possibly FN320A. But you have to rescale all your Spark tables and adjust the values within every one of those tables already. Whats another table at that point?

And as for FN320A, it's got default values of 70-78% Load% (for A9L). With Load% = Load, you'll be forcing OL well before you enter boosted ranges with those numbers so you should be safe even if you don't mess with that function. In fact, I think this function actually makes more sense being directly related to Load so regardless of what the engine capacity percentage (Load%) is, you can force OL before you get into boost. If you stick with Load% being scaled, you'll most definitely need to touch this function. With Load% scaled properly, a moderately high PSI capable engine@70% Load% could easily be under boost. And if I'm to understand boosted applications right, running Closed Loop (14.64 AFR) at boost is probably not a good plan.

But again my opinions are really irrelevant on this subject since I have never tuned a boosted application.

[sailorbob]

Since the '0' vs '1' discussion is back I will reiterate what I said in the last thread this about this subject;

Another reason for setting LOAD = LOAD% is on engines that have a great variance in VE across the rpm range. Let us say that the engine is capable of 150% LOAD at 5000 rpm but remains stock at around 65% LOAD at 1000 rpm and you have set FN035 to reflect this. Now in your 'Fuel Base Table (aka FN1307) you have the A/F ratio set at 11.5:1 in the cell at 180 deg F and 90% LOAD%. This means that when you use FN035 to calculate LOAD% you will get your desired 11.5:1 AFR at WOT when at 5000 rpm (i.e. when wanted) but also at 1000 rpm (i.e. not wanted because it is far too rich). I think this kind of problem is one of the reasons why later ecu's use the rpm vs load 'Fuel Stabilised Table' (aka FN1360).

[cgrey8]

That's exactly what I was trying to illustrate. But your words have done better.

However in the case where the engine is at close to the same Load across the RPM range, Load% scaling does better or in that case, is it a toss-up as to which is "better"?

[Frit]

On the SC's we can see over 100% load as low as 1500 rpm's, if not lower. With a positive displacement blower, you get the full boost once the bypass closes, or pretty darn close to it. With the new cam now, I can stage at idle, floor it, and see 13psi right away and it stay there all the way to 5000 rpm's in all gears...

As a thought, I think someone mentioned losing resolution and I think where that stems from is the fact the LOAD=LOAD% will only show 65% at WOT at 2000 rpm's (an example only) so all you have is the 0 to 65% range of the fuel table to control fuel at the low range BUT you still need to include the rows all the way up to 100% or higher. Now if you aritificially inflate that load number by using FN035, you now have the full 0 to 100% range to work on in the fuel tables at all ranges )only IF FN035 is setup right). In the case of the SC, we don't need that artificial inflation cause the car can make 100% almost right away.

So perhaps using PRLDSW needs to be set based on the setup of the car. If it takes half the rpm range of the motor to hit 100% load, then leaving that to 0 should be strongly considered and FN035 be setup to match. If the car can hit 100%+ in the low RPM's, then setting PRLDSW to 1 would be the way to go for its ease of use.

Just a thought.. maybe.

Frit

[Cougar5.0]

As I said to Adam in an email, I am "minimalist" when it comes to making changes. I haven't changed a single value in my spark tables as I see no reason to. I just scaled up the top rows to 100% so they would align better with what is going on. I richened the fuel table at the top right & expanded the scaling to 100% on the top 2 rows again. Since I expanded the Load Scaling starting at off-idle, I don't have to worry about it getting too rich down low - I can control the change in AFR very precisely as I hand off between the slightly richened AFR's due to the stock HEGO Bias. FN035 gives the proper load perspective over RPM - it's really quite simple - a couple of changes and logs and the handoff from closed loop to O/L while lugging is seamless. It used to get rich too fast and cause a drop-off in power at first, but I fixed this years ago after I spent a little time to understand what was going on. A little richer down low with a S/C pushing 200F air fully heat-soaked isn't a bad ping prevention tactic either :)

[cgrey8]

That makes sense. And given that I'm the exact opposite of a minimalist when it comes to tweaks in the tune, I guess that kind of explains our preferences.

I'm of the camp of if something can be adjusted, I adjust it just to see what it does if I don't already know or have a good idea just for the benefit of knowing that it does something and understanding how it works...hence all that time I spent tweaking in the HEGO settings. As it turns out, I rather prefer my version of Closed Loop control over what stock had. But then again, I'm also not working in optimal stock-installation conditions either with my truck so I have to solve problems most people shouldn't have to solve. For instance at 20kg/hr of airflow at 700-800RPMs, sometimes a LAMBSE of 14 is too rich. Other times, its way too lean. And sometimes I can watch the LAMBSEs chase the value up and then back down while sitting at the same stop sign. Why? I have never been able to explain that for sure, but I have a strong suspicion it's my MAF setup. I can't blame it on the C&L because the stock 55mm GT MAF did the same thing. What I do know is nothing that I've changed in the tune has changed this phenomenon's behavior in any way, only made the EEC more tolerant of it.

But I do have to say if I didn't have problems to solve, I probably wouldn't be as adventurous through the tune changing stuff. And thus wouldn't be nearly as comfortable changing stuff and knowing by how much I can change stuff today. Different experiences, different philosophies, different problems to solve. It's a wonder we come to any kind of agreement on anything here.

[Cougar5.0]

I don't know if I disagree that changing the switch is not just as vadid a choice as any, but other than being conceptually easier to understand, I want to point out here the other changes that will more than likely need to accompany this change. Even though my KB engine may be capable of higher loads at lower RPMs, I still drive it 99% of the time like a N/A motor and I want the around town drivability to be as close to stock as possible. If you change FN035 relatively uniformly over RPM, you can then lower FN320A proportionally and get essentially the same Load to go O/L. The fuel table will be aligned close enough after a similar "proportional" rescaling of the Load(%) axis (though being slightly richer or leaner @ O/L is usually not a big deal so long as you are in the ballpark and the handoff from closed loop is smooth enough.)

If I set the Load Switch to "1", I would likely have to lower the load required to go O/L so it would not bog and buck while lugging up a hill at light throttle & low RPMs (I had this issue after raising the FN035 at low RPM's without then lowering FN320A to match.) Now the engine would go O/L too easily at higher RPMs - say when going up a hill on the highway. Does this make sense?

[2Shaker]

...I am "minimalist" when it comes to making changes. I haven't changed a single value in my spark tables as I see no reason to.

This is my philosophy as well. Firstly because I don't have the confidence I know what all these things are and how they work together; secondly because I think Ford designed the EEC to be pretty adaptive and I am setting things to help it adapt; and finally because its not a daily driver so my seat time is quite limited in reality. I take it out on weekends and drive it around logging and some tweaking. If it was a daily driver I would be more likely o try things like Chris, but I would probably never experiment as much as he has. I have spent nearly all of my tweaking time in the area of fuel and little in the area of spark.

Hey Chris, It would be interesting to see your tune compared to Ford using BE for the compare.