Lets start a load value thread

[QWKSNKE]

Obviously since the procharger has been installed, I see a higher load value on the engine when datalogging. However I feel that it maybe to high.

Richard, since you have made massive amounts of posts on the tweecer site, have you seen anything about how load variables should be adjusted to make up for the blower load?

Talked to the tuner at Modular Power House this past weekend (we went over there for Wall96cobra's tuning) and he said that he adjust load variables with the MAF transfer curve and something else. (SCT software)

Does that sound right?

[Wicked]

Are you asking us to post our load values?

Well, when Doug datalogged my car at the last dyno day, I was seeing 175% load at 4960rpm. Load started going down after that because the MAF was pegging.
It should be 200+% up in the higher rpms if the MAF wasn't pegging.

[QWKSNKE]

Are you serious? Mine look waaaaay better than that. Cruising speed I hit around 50-60% and at WOT I see around 125-130% (I think).

I was more concerned in getting it down around 30% (or less) at cruising speed. After talking with another guy that has a procharger I am thinking that they create a lot more load than Vortech or Paxton

[Sendero]

I went to do a search but came up empty.

I believe it was one of the guys with a turbo, or 93 notch himself..... but I distinctly remember a post about load with a power added. They were recommending changing the CID (displacement) values because that ultimately controls your load calculations. If you add CID, then your calculated loads will decrease and vice versa for the smaller CID.

[Wicked]

I went to do a search but came up empty.

I believe it was one of the guys with a turbo, or 93 notch himself..... but I distinctly remember a post about load with a power added. They were recommending changing the CID (displacement) values because that ultimately controls your load calculations. If you add CID, then your calculated loads will decrease and vice versa for the smaller CID.

EXactly, but I wouldn't know why you would care about lowering your load values.

Load value is just amount of air flowed divided by theoretical(CID*RPM).
How would lowering it help you?

[Sendero]

EXactly, but I wouldn't know why you would care about lowering your load values.

Load value is just amount of air flowed divided by theoretical(CID*RPM).
How would lowering it help you?

Just an example my good man. Gotta know how it works both ways before you understand how it effects the tuning.

[Wicked]

Just an example my good man. Gotta know how it works both ways before you understand how it effects the tuning.

:jester:
You still didn't answer my question. How would a lower load value give better performance or tuning than the higher value even if the higher vaule is correct? Regardless of whether you up the CID and lower the load, its all relative.

[QWKSNKE]

I think load is what is killing my fuel economy.

There are so many tables that are based off load its not funny. (timing, fuel, etc)

[QWKSNKE]

Also,

Over 78-79% load will put you into open loop settings on a fox from I understand.

[Sendero]

:jester:
You still didn't answer my question. How would a lower load value give better performance or tuning than the higher value even if the higher vaule is correct?

Don't you think thats kind of irrelevent? We are only adding engine potential, not taking it away. Now if we were running restriced class, you could probably use it to limit HP.


Regardless of whether you up the CID and lower the load, its all relative.

Yes it is. Increase CID = lower load values. Every fuel and spark table in the TwEECer is based on load percentages. With the lower load values you have just counteracted the load the supercharger just added.

[Wicked]

Also,

Over 78-79% load will put you into open loop settings on a fox from I understand.

Okay, thats what I figured you were trying to say.

What Nathan said about raising the CID would lower the load value, but would all the fuel otherwise remain the same?

Are you talking about N/A or when you had the blower? I am guessing with the blower since surely you aren't seeing 130% load N/A.

[Italian LX]

They were recommending changing the CID (displacement) values because that ultimately controls your load calculations. If you add CID, then your calculated loads will decrease and vice versa for the smaller CID.
Tim mentioned being able to do that, but cautioned against doing it that way because it would have undesirable effects on other parameters.

[Sendero]

Tim mentioned being able to do that, but cautioned against doing it that way because it would have undesirable effects on other parameters.

He didn't happen to mention which parameters it would effect? I only understood the CID was for load calculation, but I was never told what else it was linked too.

[Italian LX]

He didn't happen to mention which parameters it would effect? I only understood the CID was for load calculation, but I was never told what else it was linked too.
I don't recall... Lee was talking to him and I was in and out of following the conversation.

[QWKSNKE]

He didn't happen to mention which parameters it would effect? I only understood the CID was for load calculation, but I was never told what else it was linked too.

We didn't mention anything specific but I would imagine there would be more than just load that would change from CID changes

[Sendero]

http://tweecer.oplnk.net/viewtopic.php?t=3234&highlight=cid+scalar

[QWKSNKE]

What about this function in the EEC Analyzer?

[Sendero]

What about this function in the EEC Analyzer?

I had read a thread on that subject and I was trying to learn more about it.

[coupe]

I don't see engine load in the 200%-range as being useful at all. Any value should be maximum at 100%; maybe a hair over. Load is calculated from MAF, throttle position, and what else? Thought that was all. That is why the MAF transfer function is critical; especially for drivability. I don't see why the blower car would see more load: it's the same throttle with higher MAFlow. I would think that would be lower load. But not sure. Good discussion.

[Sendero]

Ok, did a little digging and this is what I've found:

Load based on MAF (just for reference)
http://tweecer.oplnk.net/viewtopic.php?t=2983&highlight=load+calculation

Load Scaling Function
http://tweecer.oplnk.net/viewtopic.php?t=46&highlight=load+calculation

Actual Load vs. % Load
http://tweecer.oplnk.net/viewtopic.php?t=1778&highlight=load+calculation

Load Switching Scalar
http://tweecer.oplnk.net/viewtopic.php?t=98&highlight=load+strategy

Very interesting...

[93Cobra#2771]

You still didn't answer my question. How would a lower load value give better performance or tuning than the higher value even if the higher vaule is correct? Regardless of whether you up the CID and lower the load, its all relative.
For one, you can better control both your timing and fuel under varying boost conditions. You basically have better control over everything. From what I recall, most power adder guys mess with the CID. To be honest with you, I don't know that much about what they do or don't, as I generally don't study too hard on mods that don't benefit n/a combos.

I do recall a post where Mike Glover said he was working on a way to log boost with the tweecer, and possibly a way to reference that boost with timing and fuel.

Sendero did some good searches there. My least fav. method is prob. the MAF method...

BTW, 94 up processors base even more stuff on load - in fact, almost all calc. are based on load. 94 up doesn't even have a WOT timing/rpm scaler...

[QWKSNKE]

See, I was thinking that the load datalogging I was seeing was the load of the engine (i.e. engine working harder to run)

[Wicked]

I don't see engine load in the 200%-range as being useful at all. Any value should be maximum at 100%; maybe a hair over. Load is calculated from MAF, throttle position, and what else? Thought that was all. That is why the MAF transfer function is critical; especially for drivability. I don't see why the blower car would see more load: it's the same throttle with higher MAFlow. I would think that would be lower load. But not sure. Good discussion.

Simply put, load is how much air is flowing versus how much air should(theoretically) be at a specific RPM, TP, etc.

So, hypothetically speaking, if my N/A Cobra flows 487cfm(281*6000/2/(12^3)) at 6000rpm, that is 100% load.

If I supercharge it and now am pushing double the air, 975cfm, at the same 6000rpm, my load has increased to 200%.

Load % over 100% doesn't really mean you are 'overloading' the engine and definitely doesn't mean you are hurting power. You are just loading it past its normally aspirated airflow limit.

[QWKSNKE]

One thing to consider about load is, once you exceed 80% the EEC is subject to go open loop which is bad for economy if you are doing that while going down the road.

[Wicked]

One thing to consider about load is, once you exceed 80% the EEC is subject to go open loop which is bad for economy if you are doing that while going down the road.

But unless you are making boost or running high throttle angles while cruising you should never be pushing 80% while cruising.

What was your MAF setup? Blow-thru or Draw thru? Just curious.

From my datalogs, I've got about 25-35% load while cruising at 2000rpm in 5th and around 13% at idle.

[QWKSNKE]

blow through.

My car idles at 25-30% load

[Wicked]

blow through.

My car idles at 25-30% load

That might be a little high, what does brian's car idle at for comparison?

[Sendero]

That might be a little high, what does brian's car idle at for comparison?

Might idles between 16% to 21% dependant on which idle strategy its using.

[Wicked]

Might idles between 16% to 21% dependant on which idle strategy its using.

What RPM does your car idle at? I figure mine and yours should idle at about the same load. Mine does idle a little rough and maybe low.

[Sendero]

What RPM does your car idle at? I figure mine and yours should idle at about the same load. Mine does idle a little rough and maybe low.

It tried to idle around 650rpm but I have it set to idle around 710rpm.

[QWKSNKE]

bringing this old topic back up.

Eric and I were discussing load values the other day and his SCT book actually mentions that higher the load the more efficient the motor is. Now I am assuming that the book is referring to power and not fuel economy. I'll start another thread about that.

[93Cobra#2771]

Yes, if you are achieving a super high load, that means you are performing at the motor's max (or close to it) efficiency.

For example, blown combos will hit high 100's low 200's, while us n/a h/c/i guys feel good in the 130's or so...

[Wicked]

130 sounds high for an NA car.

Is your Pro-M cal'd for other-than-stock injectors?

[Wicked]

bringing this old topic back up.

Eric and I were discussing load values the other day and his SCT book actually mentions that higher the load the more efficient the motor is. Now I am assuming that the book is referring to power and not fuel economy. I'll start another thread about that.

Thats exactly right.

200% load means you are moving 200% of the air that should flow through it at ambient pressure. My load hits 170%(when the maf pegs at 4960) which means I am moving 70% more air than I would be if I was sucking atmospheric air.

[Doug904]

One more small thing about load at idle, don't forget that when you adjust the CID to bring the load into the correct range at idle that you also adjust the MAF transfer and the a/f ratio in doing so. SO when you do this remember to readjust the short term fuel trims first and then check your WOT a/f's as well.

High load at idle can cause poor idle conditions and even surging.

Later, Doug.

[93Cobra#2771]

My ProM is cal. for my stock 24's, but with the X3Z. Been a while since I looked at one of my load datalogs, so I may be off a little bit on my numbers.

[QWKSNKE]

My ProM is cal. for my stock 24's, but with the X3Z. Been a while since I looked at one of my load datalogs, so I may be off a little bit on my numbers.


yeah you shouldn't see more than 100% n/a. Realistically an n/a car probably will not see much over 80%

[Doug904]

My ProM is cal. for my stock 24's, but with the X3Z. Been a while since I looked at one of my load datalogs, so I may be off a little bit on my numbers.


Ahhh, then you need to scale your load to correct for the calibration factor by the Pro-M.

Do this, divide your stock injector size by the calibrated injector size and multiply your engine displacement by this value.


So you would do this 19/24 = .7916 x .0016655 = .001310 and this is your new engine displacement value because of the way the Pro-M is calibrated. This should correct your load value or get you very close, this is for a 302 size engine.

Then go back to your base load and fuel trims and adjust everything from there up.

Please excuse this if you've already done this or know this as I'm just trying to help. :)

later Doug

[Sendero]

yeah you shouldn't see more than 100% n/a. Realistically an n/a car probably will not see much over 80%

Maybe Eric could chime in on this, but what is his load under WOT. I am curious to see if Ford keeps the load range between 15% and 100% on the factory boosted vehicles.

[Wicked]

Ahhh, then you need to scale your load to correct for the calibration factor by the Pro-M.

Do this, divide your stock injector size by the calibrated injector size and multiply your engine displacement by this value.


So you would do this 19/24 = .7916 x .0016655 = .001310 and this is your new engine displacement value because of the way the Pro-M is calibrated. This should correct your load value or get you very close, this is for a 302 size engine.

Then go back to your base load and fuel trims and adjust everything from there up.

Please excuse this if you've already done this or know this as I'm just trying to help. :)

later Doug

Its a 93 Cobra, 24's were stock. :shrug:

[Wicked]

Maybe Eric could chime in on this, but what is his load under WOT. I am curious to see if Ford keeps the load range between 15% and 100% on the factory boosted vehicles.

Good question, I'd also be interested to know.

[Doug904]

Good question, I'd also be interested to know.
Nope they don't. The 03' Cobra values and Lightning value files are set up for 1.99 load.

Also, on that 93' Cobra, what is you calibration code? I'd like to look at some values to see what the computer is setup from the factory.

Thanks Doug.

[QWKSNKE]

x3z

[93Cobra#2771]

X3Z isn't much different than a9L stuff - 24/24 on injector slopes, diff. MAF transfer curve, injector timing is diff., WOT fuel is slightly richer, timing is slightly softer, 93mph "speed limiter" (pulls a little extra timing and makes a/f slightly richer) - that's the big stuff I can think of right off the bat.

You all are going to force me to pull the laptop out and check a datalog for my load values, now. To be honest, I'm not sure what it was now...

[Sendero]

Nope they don't. The 03' Cobra values and Lightning value files are set up for 1.99 load.


So does that mean the load values go all the way up to 199%? What about the fuel tables, what is their max load variable?

[Doug904]

So does that mean the load values go all the way up to 199%? What about the fuel tables, what is their max load variable?


I'm sorry, I said that wrong. The 03' Cobra Value files are set up in the spark tables to goto 1.5 load or 150% load. The fuel tables are in TPS settings so they only goto 650 and I would imagine anything above that is the same as 650 or the multiplier from there. This is for the Cal code YDH1.


X3Z isn't much different than a9L stuff - 24/24 on injector slopes, diff. MAF transfer curve, injector timing is diff., WOT fuel is slightly richer, timing is slightly softer, 93mph "speed limiter" (pulls a little extra timing and makes a/f slightly richer) - that's the big stuff I can think of right off the bat.


Now in my software I have a completely different setup. The injector slopes are very different along with Comp Batt voltages( the values changes for different size injectors). Also the MAF curve has a bit more fuel added to it. The timing at WOT only varries by one degree above 5500 rpm's, everything below is the same @WOT. These are comparing the A9L to the X3Z.

Here's a comparison file from both, file 1 is X3Z and file 2 is A9L...

http://webpages.charter.net/doug904/X3ZVSA9L.txt

Thanks, Doug.

[QWKSNKE]

interesting files.

[93Cobra#2771]

I don't recall the batt. voltage differences, but you are correct on the MAF transfer curve (93 Cobras had a 70mm MAF). Little confused on the injector slopes though, as the high and low inj. slopes are both 24 (tweecer software), with fuel trims used to control low rpm fuel.

Interesting comparision between the two, however. What software are you using? SCT?

[QWKSNKE]

..... Little confused on the injector slopes though, as the high and low inj. slopes are both 24 (tweecer software), with fuel trims used to control low rpm fuel.




Same here.


Yes he uses SCT

[Doug904]

I don't recall the batt. voltage differences, but you are correct on the MAF transfer curve (93 Cobras had a 70mm MAF). Little confused on the injector slopes though, as the high and low inj. slopes are both 24 (tweecer software), with fuel trims used to control low rpm fuel.

Interesting comparision between the two, however. What software are you using? SCT?


Yeah, I'm an SCT dealer but I dont do many Mustangs or Lightnings. My bread and butter are Ranger's and Explorer's but I do like to jump the fence every once in a while :hyper:

Still, if you had a MAF calibrated to the injector size and your load values seem off then I would scale engine displacement to just see if it helps.

Are you using the Tweeker software to datalog as well? What kind of values are you able to get with that? My EEC4 tuning is very limited because I cannot get a scan tool that will datalog enough stuff on a EEC4 car to be useful.

THanks, Doug.

[93Cobra#2771]

Load values may not be off so much as my memory... :D

Yes, using the tweecer for datalogging. You can datalog hegos, kamrf, mafv, ect, act, etc. You can datalog up to 16 items at a time, real time, for as long as your battery on your laptop holds out. Excellent datalogger...

[Wicked]

Yeah, I'm an SCT dealer but I dont do many Mustangs or Lightnings. My bread and butter are Ranger's and Explorer's but I do like to jump the fence every once in a while :hyper:

Still, if you had a MAF calibrated to the injector size and your load values seem off then I would scale engine displacement to just see if it helps.

Are you using the Tweeker software to datalog as well? What kind of values are you able to get with that? My EEC4 tuning is very limited because I cannot get a scan tool that will datalog enough stuff on a EEC4 car to be useful.

THanks, Doug.

I might take you up on that soon. I wanted to tune before the dragon.

[86GT]

X3Z isn't much different than a9L stuff - 24/24 on injector slopes, diff. MAF transfer curve, injector timing is diff., WOT fuel is slightly richer, timing is slightly softer, 93mph "speed limiter" (pulls a little extra timing and makes a/f slightly richer) - that's the big stuff I can think of right off the bat.

There are some other differences. The biggest changes are in the Managed Air Fuel Strategy. The X3Z has it disabled whereas the A9L has it enabled. The EPA has been all over Fords butt about the managed fuel strategy. For some reason it causes lean conditions durning normal driving. I'm not to sure if this is the reason it is disabled in the X3Z, but I think it is.

The deceleration fuel cut off is also different. It reacts at different speed and so on.

Forgive me for not reading the entire post but the main reason for scaling the load with the "Sea Level Load" function is to prevent the sputtering on initial take off and so on. Let me explain, If you leave the functions and scales alone then the car will actually idle at about 30% rather than 20% if you have a power adder. When you have a power adder it will increase the load around twice as fast. Lets say we have two engines at 3000rpm, one S/C and the other N/A. The S/C will load up faster causing higher spark and richer mixtures to early. This will cause the S/C car to detinate faster and foul out faster. It needs to be a gradual increase like the N/A set would do.

You can fix the issue one of two ways. You can either scale the one function previously mentioned or you can rescale all of the fuel and spark tables. Personally I believe it is eaiser to modify the one function. There are some good threads about this very subject on the Tweecer board.

[Italian LX]

Hey Clint, glad you could make it over here. :nice:

There are some good threads about this very subject on the Tweecer board.
Yeah, the TwEECer board has some wonderful information, but the search engine for the board sucks. :notnice:

[QWKSNKE]

Hey Clint, glad you could make it over here. :nice:


Yeah, the TwEECer board has some wonderful information, but the search engine for the board sucks. :notnice:

:werd:
This is why I created the EEC room on this forum.

Welcome Clint and thanks for joining up. :nice:

[86GT]

Thanks for the welcome and glad to be here. Lots of reading to do!!! :popcorn:

[wldtang]

Ahhh, then you need to scale your load to correct for the calibration factor by the Pro-M.

Do this, divide your stock injector size by the calibrated injector size and multiply your engine displacement by this value.


So you would do this 19/24 = .7916 x .0016655 = .001310 and this is your new engine displacement value because of the way the Pro-M is calibrated. This should correct your load value or get you very close, this is for a 302 size engine.

Then go back to your base load and fuel trims and adjust everything from there up.

Please excuse this if you've already done this or know this as I'm just trying to help. :)

later Doug

I am confused by your math.
In my case my car had 24's. I switch to 42's. My CI is 302.
Would this mean 24/42 = .5714 x 302 = 172 cubic inch?

I have a supercharger and want to try to get my load tables correct.
I am seeing a load of about 197.

[QWKSNKE]

What kind of car do you have and what strategy is it?

[wldtang]

I just put together my sig.
I am running the cabaza with J4J1

[Dale McPeters]

I am confused by your math.
In my case my car had 24's. I switch to 42's. My CI is 302.
Would this mean 24/42 = .5714 x 302 = 172 cubic inch?

I have a supercharger and want to try to get my load tables correct.
I am seeing a load of about 197.

Yes that is what Doug904 is saying. "Pro-Tuners" have been doing this for many years as their time is limited and can get very expensive for the persons car that they are tuning. I personally only agree with doing this when absolutely needed on the '88-'95 EEC's. One example would be like when running "LOTS" of boost "BIG" cubic inches like 502cu/in just an example.

Later model EEC-V's up thru '04 will be a little different depending on car modifications etc. and what the load scaling switch is set to.

One example would be on the '03-'04 Mach 1 cars (as I am more familiar with these) as you can still scale load by the function sealevel load scaling (or peak load at sea level). You can also effect load by the maf as they are load based like the J4J1.

The main thing is to make sure that you hit the correct rows etc. in the fuel and spark tables (or calculated spark) at the load your are seeing in the datalogs and do not exceed the EEC's limitation of 199% load.

If your tune changes over a period of time then "normally" the maf curve is the culprit and adaptive is having to compensate to much.........

[wldtang]

In this case would I change displacement to 172 ci? It seems I should go the opposite direction.

[exgmguy]

My car was idling at 35%, and would hit 100% with a very small amount of throttle. I think this was causing a part throttle rich condition. I added to the sea level function, and changed my cubic inches (in Scalars) to 351. My load at idle went down to the mid 20's.
My laptop battery died so that is as far as I got today. :metal:

[Dale McPeters]

My car was idling at 35%, and would hit 100% with a very small amount of throttle. I think this was causing a part throttle rich condition. I added to the sea level function, and changed my cubic inches (in Scalars) to 351. My load at idle went down to the mid 20's.
My laptop battery died so that is as far as I got today. :metal:

Use the sea level load scaling and save the cubic inch displacement for when it is really needed........like higher psi of boost.

Note this is MHO.....YMMV.