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Topic: SEFI conversion to MAS (Read 8802 times) previous topic - next topic

SEFI conversion to MAS

Reply #15
You need a tune.  I have been exactly where you are, and YOU need a tune.
also, you need a 70mm MAF housing with a swappable sample tube, and you need the tube recommended for 19 lb/hr injectors, so you don't have to dick around scaling your MAF transfer table.  Calibrated MAFs shag up the load calculation, and by proxy, spark advance.
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SEFI conversion to MAS

Reply #16
If one is buying a Quarterhorse you can just skip the calibrated MAF and buy a 90mm Lightning MAF. Since the Quarterhorse can tune that MAF it's usually the best option.

OP: Pull the codes first. Let's see what we're working with. Pull KOEO, KOER, and run a cylinder balance test. Also what is fuel pressure? Engine vacuum? Check all these things before buying any parts.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

SEFI conversion to MAS

Reply #17
Quote
If one is buying a Quarterhorse you can just skip the calibrated MAF and buy a 90mm Lightning MAF. Since the Quarterhorse can tune that MAF it's usually the best option.

Or just tune the one you have....... Nothing special about the Lightning MAF. You input the actual flow and adjust from there. A calibrated​ Maf only causes issues with load, timing, idle , cold/hot starts, tip-in, tip-out, transient fuel, crank fuel, failed Maf and adaptive fuel if you dont tune the Maf AND injectors into the ECU. This is more important with a stick car since it runs unloaded much more often than an auto that masks the issues.

But agreed.....Do the simple stuff first because you can't​ tune out mechanical issues.

John

SEFI conversion to MAS

Reply #18
Quote from: Skunk;459821
Or just tune the one you have....... Nothing special about the Lightning MAF. You input the actual flow and adjust from there. A calibrated​ Maf only causes issues with load, timing, idle , cold/hot starts, tip-in, tip-out, transient fuel, crank fuel, failed Maf and adaptive fuel if you dont tune the Maf AND injectors into the ECU. This is more important with a stick car since it runs unloaded much more often than an auto that masks the issues.

But agreed.....Do the simple stuff first because you can tune out mechanical issues.

John
Glad to see someone who understands.  He can run any MAF he want's if he can get the MAF transfer tables that match it.  Using a MAF housing calibrated to stock injector size allows the use of the stock MAF transfer table, which I have found to be the most accurate (you can get the extended table that goes all the way to 4.9v for better use on engines that will clip the table).  To use a MAF calibrated to a different injector size, he has to take the stock table and scale it using math, and I've found that even after the best math, you still end up having to fine tune the table.  With the stock table unscaled on a 19# calibrated MAF, it's simpler to just fine tune the injector slopes and breakpoint.

Note on the Quarterhorse: you don't flash to it, you load to it and your tune is held in volatile RAM with a backup battery (cr2032) which is now replaceable.  The QH is an emulator, not a flash module (why it's better than a twEECer).  This is why you can make live changes with it while the engine is running.  Keep your current tune backed up to your laptop (and the cloud) always in case after a few years the battery needs replaced.

SEFI conversion to MAS

Reply #19
Lol......Ya I have a little experience. I'm running 42# Injectors and a calibrated blow-through PMAS Maf on my 5.0T Turbocoupe. I needed the calibrated Maf to extend the usable range. In my experience over the years... A 19# calibration will come close to pegging once you do the HCI upgrades then you need a calibrated Maf or a larger pipe to keep it from hitting it's limits.. I always try to tune injectors using the factory 55mm MAF to make sure fuel is controlled though the entire range of the MAF.......Then install the Maf and tune it. It's much easier to tune in when using known variables not to mention even an aftermarket 19# calibration is seldom perfect.

Quarterhorse vs Tweecer..... They both have their place and I use both. I prefer the Tweecer for finished permanent installation but like the Quarterhorse for all the reasons you listed.

John

SEFI conversion to MAS

Reply #20
Quote from: Skunk;459821
Or just tune the one you have....... Nothing special about the Lightning MAF. You input the actual flow and adjust from there. A calibrated​ Maf only causes issues with load, timing, idle , cold/hot starts, tip-in, tip-out, transient fuel, crank fuel, failed Maf and adaptive fuel if you dont tune the Maf AND injectors into the ECU. This is more important with a stick car since it runs unloaded much more often than an auto that masks the issues.

But agreed.....Do the simple stuff first because you can tune out mechanical issues.

John

I just recommended the Lightening MAF due to it's known transfer function and it being cheap. Any MAF will work if you know its transfer function. A Pro-M or PMAS MAF usually include a transfer function sheet. The BBK MAF the OP has probably does not have a transfer function sheet and he'd have to create one.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

SEFI conversion to MAS

Reply #21
......That quoted post was supposed to say "you CAN'T tune out mechanical issues." I will try to go back and correct it.

Anyway.....Sure the Lightning MAF is known......But only when used in a Lightning. Otherwise it's transfer is a starting point and needs manipulation for proper use in an Eec-iv ECU considering your not using the entire intake from airbox to TB. The eec-v generation of ECU also handles air and fuel differently so the Eec-iv needs more work to get things properly done.

The BBK transfer is easy. They even tell you how to do it on their website. The 24# transfer is simply a ratio of injector change. 19/24. Multiply the stock airflow by the result and tune from there.......Believe me , even having a transfer sheet means squat. A bench flow and installed flow will vary and tuning is always recomended. This is where the C&L sample tube system shines. You can physically alter or change the sample tube to manipulate fueling if you don't want to tune it. It will still screw alot of other things up but it's manageable and can run very well.

John

SEFI conversion to MAS

Reply #22
So how many more horsepower and foot/pound will I pick up by tuning the right way, rather than slapping a MAF cal'd to my 24's?

Mine is (will be, better to say) an occasional driver, 2-3 times a week, no racing, just a fun little car to zip around in back and forth to work. I don't care about mileage, but off idle acceleration and overall drivability needs to be normal. I also don't have a lot of money to throw at it, either in the tuner/tuning components, and the ability to do so myself. (do have a few laptops and am computer savvy, so I could learn how, I reckon..)


My combo is a stock bottom end 5.0, P heads, E cam, cobra intake, 65mm TB, blah blah. The usual, nothing major at all.....
'98 Explorer 5.0
'20 Malibu (I know, Chevy, but, 35MPG. Let's go brandon, eh)

SEFI conversion to MAS

Reply #23
I don't see why you would bother to go through the effort of a maf upgrade. Essentially  all maf does is measure  airflow rather then predict it. It's just adding extra sensors you don't need it you are gonna tune it anyways.
Quote from: jcassity
I honestly dont think you could exceed the cost of a new car buy installing new *stock* parts everywhere in your coug our tbird. Its just plain impossible. You could revamp the entire drivetrain/engine/suspenstion and still come out ahead.
Hooligans! 
1988 Crown Vic wagon. 120K California car. Wifes grocery getter. (junked)
1987 Ford Thunderbird LX. 5.0. s.o., sn-95 t-5 and an f-150 clutch. Driven daily and going strong.
1986 cougar.
lilsammywasapunkrocker@yahoo.com

SEFI conversion to MAS

Reply #24
Ive been bored waiting for warmer weather so ok I will bite.

Quote from: ThunderbirdSport302;459831
So how many more horsepower and foot/pound will I pick up by tuning the right way, rather than slapping a MAF cal'd to my 24's?

LOL.......absolutely none. Matter of fact your numbers may drop until you tweak the timing tables. You dont need to tune but if you had the ability to look at the raw data like OBDII you would understand why you should.

Garbage input equals garbage output. Think about getting in a elevator every day and pushing the button for the 10th floor except the elevator always takes you to the 9th floor because the elevator thinks the 9th floor IS the 10th floor..... You think your smart and start pushing the button for the 11th floor.......... WTF. You accept this as normal or lol running good .......why??? A calibrated maf without a tune does the exact same thing........ with 24# everything is off by almost 21%. Maybe its my OCD but If I order fries and get onion rings.....I get pissed.

This is where the Tweecer or Quarterhorse comes in. They both give you the ability to look at and log live data from the ECU. With that knowledge you can regain perfect or depending on your ability, near perfect feedback control (closed loop) of your engine. Once you crack that...........move on to the WOT (open loop) power tuning by unlocking the factory warranty safe, mass production tolerant lock down and bleed it for everything you can get.

John

SEFI conversion to MAS

Reply #25
SOOOOOO ran flash out == i have codes for right and left 02s lean --- car is running super rich

SEFI conversion to MAS

Reply #26
LOL.....ya sorry for the hyjack.

Was that a running or stored code. Are you sure its rich......do you have a wideband or did you read the plugs? You cant judge based on smell or burning eyes.

John

SEFI conversion to MAS

Reply #27
Quote from: 20thanvcat;459839
SOOOOOO ran flash out == i have codes for right and left 02s lean --- car is running super rich

If you have lean codes (41, 91 KOER) it might smell rich. If the car is registering lean the computer will dump more fuel.

So causes could be:

Vacuum leak

Bad O2 sensor ground

Exhaust leak

Line between the throttle body and valve cover missing (vacuum leak)

Can you put a vacuum gauge on the car and report the reading? I bet your engine has a vacuum leak somewhere.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

SEFI conversion to MAS

Reply #28
so pulled codes (flash out ) KOER i have lean non switching codes on o2,s  both banks ---    so question is when the o2,s fail they fail in lean mode ? so they richen fuel to comp ?

SEFI conversion to MAS

Reply #29
No not always. In this case the ECU cant get the o2s to switch upwards past about 0.45v by adding fuel. After so many cycles it gives up and you start running off the open loop fuel table with no correction. Depending on how accurate your MAF is will determain how rich or lean you run.

The fact that its both banks makes me wonder what you did with the HEGO ground. You know ....the orange wire that is supposed to be attached to a stud at the back of the intake. I suggest you take out the o2s, wipe them down and wire brush the bung to ensure a good ground to the pipe if the Orange wire is good. How old are they?.....they may simply be done and time for new ones. You can bench test them while you have them out if you wish but it may be best to replace them anyway.

John