my 393 started breathing today!

what about sample tube size..... the bigger the injector the bigger the sample tube diameter or the bigger the injector the smaller the sample tube diameter? the reason i ask is my sample tube thats in there now has fant green on the back of it however it is wayyy smaller in size then my sample tube for 24lb injectors.

is there a way to determine what size injector the sample tube is for other then the paint on the back of it?

so u didnt get a tune then right? what kind of maf are you running?

i just read a thread on a site that was explaining how sample tubes can lower an engines VE because the eec doesnt know the true rate of air being consumed by the engine, it also stated that any after market maf works the same way, weather its just changing the sample tube or changing the transfer function of the meter. i definately want all of the VE i can get, dont really think getting 10mpg is anything i would be happy about with a brand new engine.

i am now more confused then ever, no offense to anyone at all but it all kind of seems to be a matter of opinion. the thread i just read had 2 guys going back and forth about which was correct, either changing the maf on tricking the computer or running a stock meter and just changing the eec's programming to match it. i completely understand that everyone is different and what works for some people might not work for others but what is actual fact here??

is changing the maf and sample tube to match my injector size going to do absoultely nothing? personal experience in the past says it works perfectly fine as i ran 24lb injectors and a blue sample tube in a 73mm C&L and got 20mpg with 4.10 gears running a 2400 stall in an aod

is changing the eec programming going to fix anything if the meter and sample tube dont match the injector size? one guy was saying he is running a 73mm C&L with a red sample tube (30lb injectors) and 48lb injectors and it ran perfectly fine because he had the eec programming changed.

here is my question, if changing the sample tube(C&L) is in a round about way changing the eec's way of thinking or having the transfer function changed on a meter (pro-m) then why worry about having the eec programming changed just to try and match up a weird set up such as the guy running the 73mm C&L with a red sample tube(calibrated for 30lb injectors) and 48lb injectors. it all seems like 3 different ways of doing the exact same thing. can someone explain this more in depth to me so i can try and comprehend the differences or reasoning of why one is better then the other

this is on c&l's calibration chart page

C&L MAF CALIBRATION GUIDE

The following is a list of the most common sample tube applications for various vehicles using our mass airflow products. Each calibration tube is easily swapped out by simply removing the two allen head screws at the top of the unit, located just under the electronics module. There is no need for you to send the unit to us for re-calibration, and you get to keep your old calibration for possible future use.

Mass airflow transfer function sheets for the most popular applications are available upon request (via fax or email). We only recommend the use of transfer function definitions in high horsepower supercharged applications, or in situations where a radical combination (extremely large camshaft) has been used. We have received requests from people who have tunable computer systems who want transfer functions for stock or slightly larger injector applications. This is totally unnecessary, as our calibrations have already been fine-tuned on the dyno for the best air/fuel ratio. Re-defining the MAF transfer table in such an application would cause the air/fuel ratio to revert back to the richer (and lower performing) stock level. You would then have to manually adjust the WOT fuel table just to get back to the power level that you were already at with the standard MAF transfer function.

If you are not actually using a dyno to tune the computer, you will most likely end up making LESS horsepower than you would with a completely stock computer and typical timing adjustments. The use of a dyno is completely necessary whenever you use a system that gives you total control over all of the computers vital functions.

just changed the tps, seems to be more responsive.

i also went to r&e and the only sample tube they had in stock was for 30's i brought both my 42 and 24 sample tube with me so by comparsion of the 30 to the 24 the bigger the injector the smaller the diameter of the sample tube which means my 42 sample tube probably really is for 42's

it was 41 with the vacumn hooked up and around 45 with the vacumn disconnected. i lowered it to 39 and without a doubt has been the single largest improvement in how it stumbles. it did absoultely nothing for the idle quality but it must have cut how bad it stumbled in half.

with it not stumbling half as bad as it was can i go further down in fuel pressure to see if it improves more, if so how much further down can i go but still remain safe?

is this a sign that my injectors are too big since id be going lower in fuel pressure?

it doesnt smoke at all anymore, i was sucking oil from the pcv, i took the top of the engine apart and realized i didnt install the baffle on the lower intake for the pcv so that problem is solved. now i just have stumbling while driving and idle issues.

if interested check out this article i found about setting fuel pressure and adaptive learning of the eec. its pretty good
http://www.mustangworks.com/index.cfm/page_id/3/content_id/336

ya i cant even begin to tell you how stupid i felt after realizing what it was. i just gotta get the idle and stumbling figured out and she will be ready to rock.

im really hoping that the more i start it and take it around the block the more the adaptive learning will iron out the stumbling, the idle im not sure about, i can get it to idle perfect at about 900, but that seems drasticly too high, the fcam is pretty big but it isnt that big. anything under that and it revs up and down over and over again, it has me pretty stumped.

notice the oil already coming out before i even had the side cover off

By badass79cj5, shot with DSC-P200 at 2009-01-11


By badass79cj5, shot with DSC-P200 at 2009-01-11


By badass79cj5, shot with DSC-P200 at 2009-01-11

ya thats absoultely amazing that all that came through the pcv isnt it? ya i spent a good bit of time cleaning it all out, once i installed the baffle and put it all back together and started it she smoked for about 20 seconds and then cleared up and hasnt smoked since. (THANK GOD)

really.....hum maybe im shooting for something that isnt going to happen then huh? whats your tps voltage at? i cant even hear the lope in my cam when i get it to idle that high. ill toy with it again in the morning and see what i come up with, ill take another video so you guys can tell me what you think. by the way riceslayer yours sounds great, i watched your latest video alittle while ago!

i just read this on the surge idle checklist, im confused about what it is actually saying... what part of the iac are you drilling out and how does this actually help?

99% of the time on a cammed car opening up the divider between the ports on the IAC with a dremel so the motor idles at 1000rpm with the IAC unhooked, the throttle plate shut and the TPS at .98vdc fixes all surge related problems. Found about to do that on my '93 with a very mild cam and good induction it didn't like idling below 900rpm. The IAC can't react quick enough to a lopey cam induced RPM fluctuation so instead of dampening the surge it increases it. Every E cammed car I've ever worked on needed this to keep a stable idle. Similar to Fords idle bypass plate without the cobbled look. Just dremel out a little at a time till it idles around 1k. In my experience the stock puter doesn't like to idle a cammed car down low.

so after chasing a few items on the surge idle checklist i finally said screw it and took the car to brandt racing to see what his thoughts were on it.

he said without a doubt my throttle body is too small (70mm) for running on such a large inch motor. he suggested a 75mm accufab so today i bought one and a egr spacer.

i then asked him what he thought about my intake since it is a 70mm, he didnt suggest getting a different intake just porting the one that i currently have. what do you guys think as far as that goes? there is a performer rpm on ebay right now i was eyeballin if it is a much better intake to begin with then what i currently have

he also said that with me lowering my fuel pressure lower then stock and that making such a drastic difference in how it was stumbling throughout the rpm range is a sure sign that 42's are too big for my current setup. so i found some 30's here locally and bought them today as well

i didnt really want to spend the money right now on different parts and was really hoping to get it running right with the current setup but with buying the new stuff and turning around and selling the old stuff im not out that much money in the grand scheme of it all. i think im gonna hold onto my 42's for now so they are on standby once i am able to land a sweet deal on some afr's. after talking with brandt and realizing that he has been building and racing mustangs for 25 years and has the fastest limited car in the country i figured i should probably take his advice.

tiptop said:

ya, if flooding pretty bad, see if you can borrow a set of 30 pound injectors, put them in and im sure it will be all right, like i said eariler and i know its pretty hard, but you have to put a few miles on the car to seat everything, and get everything broke in, compression looks very good, so no worries there, just 2 rich, borrow them injectors or buy them, then take them bake or resell them if you have too, im sure it will be all right then.

Click to expand...

alright alright alright, dont kick me while im down! just kidding. ya i was set on getting the 42's to work but you gotta admit defeat sometimes. ill keep them around though for when i upgrade, im sure it wont be long before i need them with a few more upgrades such as afr's

yes i cleaned up my plugs really good and reinstalled. when you stated that could be why i was getting weird o2 readings you are refering to while it was trying to burn all of the oil correct? dependant upon how much oil it is trying to burn at that perticular time could cause it to read that it is back and forth too rich or too lean?

i cant see why 42's wouldnt work with my combination but with nothing else working i wanted to try something different especially after talking with gary brandt about it. i dont know if you had the chance to read that link i posted about adaptive strategys and setting fuel pressure but it is pretty good and completely makes since for what is going on with my car. ill post it again. i wouldnt ever debate the fact that getting a professional tune wouldnt clear up some of my issues if not all of my issues but for what my future plans are i just cant justify spending 500-600 bucks on getting a tune for my current combination only to eventually change to afr heads and then have to spend the 500-600 over again to get the computer retuned to the new combination. i could be completely wrong but it doesnt seem very cost effective going that route.

ive been reading alot about adaptive strategy and how the iac works at different times and the more i read the more i understand how they all play into each other but i still cant pinpoint my exact problem or problems. my understanding on how the fuel pressure works according to the adaptive strategy is that you can lower or raise the fuel pressure as far as you want (within the adaptive strategy limits)and the adaptive strategy will just lengthen or shorten the pulse width of the injectors to reach the afr that it wants for that perticular burn cycle. im at 37psi now and it runs the best it has been but i took that as to mean that i must have too big of an injector and if i stepped down a size on the injector then i would be able to put my fuel pressure back to 39psi where it wants to be to begin with and the adaptive strategy would lengthen the pulsewidths of the 30lb injectors for more fuel instead of lowering the pulsewidths of the 42lb injectors. i also understand that there are max duty cycle limits of a given injector size but isnt it a better idea to run a set of injectors at say 90% instead of running them at 30%. obviously those are totally inaccurate duty cycle estimates of what i would actually be running, i just threw those numbers out there.

i read somewhere that the larger the throttle body the better chance on getting a smoother steady idle which makes since because at idle the iac is open and providing the engine with air while the butterfly is closed. on that note the iac opening is only so big so its only going to flow so much more additional air. just to get my car to idle i have my idle screw set to where the butterfly is far from being completely closed, so hopefully by stepping up a size on the throttle body that will help cure some of those issues. on the surge idle checklist i read that some guys that have a big cam will open up the divider between the 2 ports in the iac which would allow more air to flow through at idle but with me just having a f-cam i shouldnt be close to having a big enough cam to where i would have to consider that would i, or because it is such a big displacement stroker should i try it?

its all a work in progress with a huge learning curve as i have definately been put in my place and have realized that i am not as smart as i thought i was with these cars. i am willing to read and learn anything that can be taught so if anyone has any advice or suggestions on other things to read please feel free lay it on me.

"Without being able to go in and alter the fuel trims or the abililty to look at a wide-band O2, playing with the fuel pressure is like taking a wrench, pliers, and a hammer into an operating room and making a best guess instead of diagnosing with a cat scan and using surgical instruments." awesome analogy, i like that!

here is that article i was talkin about, lemme know what you think...

Author: Mike Wesley

Welcome to the wonderful world of EEC electronics! (pronounced "EEK") This is the first in a series of articles here on The Mustang Works dealing with the EEC. We will be discussing various aspects of the EEC in a Mustang. By understanding how the EEC controls the engine, hopefully you'll get a better idea of why some changes to your engine may or may not perform as you expected. Through a series of articles, we will go through major sections of the EEC and how they work with common aftermarket parts. Some of this might be old news to a few, but alot of it goes way beyond what has ever been written before. In each issue we will go through sections like: Adaptive Control, MAFs and Injectors, Closed Throttle / Part Throttle / Wide Open Throttle, Sensors and what they do, Replace the EEC or Re-Calibrate, Fooling the EEC, Fuel Control, Spark Control, Speed Density Vs. Mass Air, Power Adders and the EEC, and EEC Transmission Control.

I'm sure you've all heard something about the EEC's Adaptive Control system, but what exactly is it, and what does it do? Before we get into the Adaptive Control system, let's define a few common terms:

SPEED Another term for RPM
LOAD Roughly volumetric efficiency or how much air is entering the engine over how much it can hold.
CLOSED LOOP Fuel control when the EEC is using the oxygen sensors as feedback to control the fuel injectors
OPEN LOOP Fuel control when the EEC is relying on tables to control the fuel injectors
WOT Wide Open Throttle

The Adaptive Control system is used to correct changes in engine operation caused by variations in air metering and fuel delivery devices. The Adaptive Control system corrects the problems of variability by making changes to fuel flow based on what it has 'learned' about the system. If your engine is running leaner than it should, the Adaptive Control system can richen the system up automatically. The same thing if it is running a bit rich. The EEC has a special block of memory called the Keep Alive Memory where it stores information about how the engine is operating. By looking at the oxygen sensors, the EEC can tell if the amount of fuel it is delivering is the same amount actually going into the cylinders at a given Speed / Load point. In the Keep Alive Memory, there is a table that represents Speed / Load points normally used during Closed Loop control. As the EEC reads the oxygen sensors, it updates this table if it finds any differences in the fuel delivered and the A/F ratio measured. As an example, we will look at how the Adaptive Control system works if fuel pressure is something other than stock.

From this example, you'll quickly see why an adjustable pressure regulator might not be a good investment of your money. Ford uses a fuel pressure of roughly 39 PSI to rate it's fuel injectors. The fuel regulator operates in conjunction with manifold pressure to keep the delta pressure across the fuel injectors at roughly 39 PSI at all times. In the EEC calibration, there is a number that represents the size of the injectors installed in the engine. This number represents how much fuel the injector will flow at 39 PSI. The EEC uses this number, along with airflow information to correctly calculate A/F ratio. Based on the airflow number and it's target A/F ratio, the EEC pulses the fuel injector to give just the right amount of fuel to reach it's target A/F ratio at any given Speed/Load point. Now if you were to increase the fuel pressure, the amount of fuel delivered for a given pulsewidth would go up since more fuel will be forced through the injector. As soon as the EEC goes into Closed Loop control, it will 'see' this increased fuel pressure. The reason for this is for any given pulsewidth, the A/F ratio as measured by the oxygen sensor will be richer than what the EEC wanted it to be since now there is more fuel delivered with the same pulsewidth. The EEC will calculate the difference from what it wanted and what it got and update the Adaptive table with a 'correction factor' and use this correction factor to reduce the injector pulsewidth the next time the injector fires. Eventually what happens is the EEC is able to 'dial out' the extra fuel that was added by increasing the fuel pressure. Now you can probably see why raising the fuel pressure is only a temporary 'fix' for a lean problem. Soon you will be right back where you started from. The EEC is continuously updating the Adaptive table anytime it is in Closed Loop.

"What about Open Loop?" you might ask. Well, it works there too. This fact alone is know by very few people. Most people think Adaptive only works when in Closed Loop. This is wrong! Adaptive is only UPDATED during Closed Loop. It would be silly to ignore changes in the air and fuel system in Open Loop and only correct them in Closed Loop. If you have a serious fuel problem, your car might not even start if the EEC didn't have some way of correcting things all the time. The way the EEC uses Adaptive in Open Loop is similar to Closed Loop except it doesn't update the table. This means it's not looking at the oxygen sensor for feedback. It is merely relying on the information stored in the table to make corrections. Since the Adaptive table only contains Speed / Load points normally seen during Closed Loop, where does the correction factor come from if I'm at WOT? Good question. The answer is; it uses the last value it was using while in Closed Loop. Since the Keep Alive Memory has power to it even when the ignition key is turned off, the Adaptive table retains it's information. The only way to clear the Adaptive table is by disconnecting the vehicle's battery. Do that and you're back to working with a clean slate and the whole process starts over again. Now there are limits to how much the Adaptive Control system can change the calibrations. The adaptive system has a range of roughly +/- 25%. If you had an adjustable fuel pressure regulator installed, and you needed more fuel, you could keep cranking it up until the EEC could no longer dial the fuel back out. The problem with this is you will set a code and the 'Check Engine' light might come on.

A quick tip. When setting your fuel pressure, always check it with the vacuum reference DISCONNECTED! The pressure reading with the vacuum connected to the regulator depends on how much vacuum your engine pulls at idle. Depending on your camshaft, this can vary quite a bit. If you have a big cam and set your idle pressure to 32 PSI with the vacuum reference connected, you might only be getting 36 PSI at WOT. It's VERY important to set the idle pressure with the vacuum reference disconnected. This way you know for sure how much fuel pressure you get at WOT.

here is another article i found on fordfuelinjection.com regarding adaptive strategy as well. the last 4 or 5 lines are what really has me thinkin maybe i should just say screw it, bite the bullet and just have it tuned.

Adaptive Strategy
Now this one is a little complex. EEC likes to toy with the fuel ratio at random. It does this to run complex math equations. She is calculating how much fuel is required to reach certain lean or rich states. Why you ask? Because playing this cat and mouse game with the fuel ratio allows us to fine tune the engine parameters in other strategies. Confused yet? EEC cuts back on the injectors for a spit second and counts how long it takes for the HEGO to report back a lean environment. EEC leans and enriches at different amounts and get back different numbers. These numbers tell EEC if the engine needs a tune up, or if you’ve added a performance parts and allows us to actually alter the fuel amount delivered. What do we do with those numbers EEC collected? Well there is a Table called “Adaptive Fuel Table” (makes sense huh?) This table is used as a multiplier, it is held over the master load table. It then multiplies each number in the master table to get a better control of fuel delivery over time. In a computer that has been just connected to the battery it is full of “1’s”, if you multiply the master table by “1″ you get the same number. I’m not good at math and I understand it, 14.7:1 X 1 = 14.7:1, simple!. After many days of driving on the highway it begins to fill with multipliers like “1.2’s” and “0.9’s”, which will alter the master table. Don’t believe me? 14.7:1 X 1.2 = 17.6:1, and 14.7:1 X 0.9 = 13.3:1, and we just fine tuned our fuel curve without doing anything special. Isn’t that cool? Well not always, this entire technology depends on the Oxygen Sensors being fresh, clean, new, and in good condition. And it can’t be responsible for displacement changes, cam changes, or other big performance add-on’s. This technology is only meant to keep EEC on the same level as an ageing engine with diminished performance. It is not meant to be relied upon for performance engine tuning!

lol...sorry... got some good news, i was gonna try opening up the divider between the iac ports but first i found another iac i had laying around the garage so i installed it. i then started messing with the clocking on the mass air meter again, this go around i went a full 90 degree turn to the left meaning that the element which is normally on the top of the meter is now facing the passenger fender and the plug comes up from the bottom...make since? i then reset my base idle once again with my adjustments.

started her up and was idling all over the place so i thought i completely wasted my time, backed her out of the driveway and reved it up, immediately when the rpm's dropped it stopped on roughly 750-800 so i started feelin pretty decent. went around the block and got in it a few times, pulls like a freight train with no stumbling at all. couldnt believe it. dont know weather it was the iac or the clocking that made the difference but she is runnin pretty good. i did notice that it seems to loose power about 3500rpm though. dunno what thats all about. hope it gets better but if not its acceptable till i can get a tune. now my remaining problem is the tapping sound once its warmed up. gonna look into that next.

this video is 14 degrees timing, tps voltage .94, new idle

Video of new idle - Photobucket - Video and Image Hosting