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Topic: Changing a A9L to Mega Squirt (Read 3298 times) previous topic - next topic

Changing a A9L to Mega Squirt

I'm trying to replace my A9L because no one here in Southern Nevada can tune it. They have a problem with OBD-1. Will a Mega Squirt work? Is it OBD-2? I'm not a computer whiz so I don't know if there is something out there that is basically plug and play?
I'm not positive but I think the modifications I have done exceed the capabilities of the A9L.
Appreciate the help.
1987 Turbo Coupe, 306, Trick Flow Track Heat heads, Comp Cam, Trick Flow Pistons, Eagle Rods, Center Force clutch, T-5, 8.8 w/373 gears, and a bunch more

Re: Changing a A9L to Mega Squirt

Reply #1
I'm not familiar with Megasquirt. I chose Holley EFI over continuing to tune using TwEECer and A9L. The Holley works well and I found it easier to tune around the larger displacement and larger cam compared to A9L.
11.96 @ 118 MPH old 306 KB; 428W coming soon.

Re: Changing a A9L to Mega Squirt

Reply #2
Check out Moates, I use the quarterhorse on my A9L running binary editor to tune it. Theres plenty of youtube video tutorials and Dave is very responsive with any questions you might have.

https://www.moates.net/




http://www.efidynotuning.com/

Good info here although it is mostly pretty in depth.


Cant speak to the megasquirt, out of my price range.


Re: Changing a A9L to Mega Squirt

Reply #3
I'm trying to replace my A9L because no one here in Southern Nevada can tune it. They have a problem with OBD-1. Will a Mega Squirt work? Is it OBD-2? I'm not a computer whiz so I don't know if there is something out there that is basically plug and play?
I'm not positive but I think the modifications I have done exceed the capabilities of the A9L.
Appreciate the help.
You can get a Plug-n-Play MegaSquirt for $840. Since you don't have a stock HO, you'll also need a wideband O2 sensor too. Another $150-200. You'll also need to tune it or somebody to tune it. If you aren't a 'computer whiz', I probably wouldn't recommend it.

MegaSquirt isn't OBD-2 or even OBD-1 (which is just a catchall for any ECU that has some sort of diagnostics and is able to tell the end user.

I'd wager a large bet you haven't exceeded the capabilities of the A9L. Even though it's 30 years old, it is still more advanced than any MegaSquirt, Holley, etc for basic drivability parameters (it doesn't have capability for data logging, boost control, etc, but if you've ever looked at the GUFB strategy dospoogeent you can see how complicated it is. Designed to make the vehicle drivable and emissions complaint in any possible environmental condition. It has orders of magnitude more development man hours put into it than MegaSquirt/Holley/etc)

The downside to the A9L is it can be hard to tune because of the complexity of the strategy. Megasquirt is much easier to tune because it doesn't have all of the emissions or complicated edge case drivability dependencies. Holley is easier than Megasquirt.

Cougar 5.0 went Holley, but his exact route requires putting in a carb intake and a full re-wire. (Correct me if I'm wrong!)
Holley has other options, but I'm not super familiar.

Personally, if you aren't interesting into dumping a bunch of labor/$ into your car, I'd try and find a shop (even if it's down the road a bit) and tune your current A9L as you're N/A and don't have an extreme setup.

Re: Changing a A9L to Mega Squirt

Reply #4
You don't "need a tune" for your combo to work. I've been running my combo for years on nothing but a calibrated MAF, idle, and timing adjustments. It runs fine about 95% of the time. I only have some warm start idle surge in cold (below 50*) weather.

Now would my car or your car pick up some driveability or power with a tune? Of course. Is it absolutely necessary? Not really. If you'd like it tuned find a tuner. There has to be one near you. Don't ditch the A9L with such a mild combo.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

Re: Changing a A9L to Mega Squirt

Reply #5
First I'd like to say "THANK YOU" for the help. You guys talked me out of spending a bunch of money on something I don't really need. Most of what I know about the Ford ECM I've gotten from a book called "Ford Fuel Injection and Electronic Engine Control" by Charles Probst. That is the reason I stuck with the Ford fuel injection instead of a carb or throttle body fuel injection. Both would of been a lot easier. Neither would work as well.
My goal was to build a fairly quick, mild mannered street car. I'm a real novice when it comes to building a car. This is my first using a ECM and fuel injection. Spent a year researching before I decided on what parts I needed for this last rebuild. I've had a couple of race cars in street clothes. Impressive at the track and stop lights but a real pain in the ass. You spent more time working on them than driving them.
I had a lot of help from a friend who let me use his shop. He's a master fabricator and designed and built the 1/8 boxed steel frame connectors and the metal fab on the cowl hood. His advice on building the motor kept me from screwing up. Took me 3 months working 6 days a week. At the moment the only original parts on the car are the body, windows, and interior. The parts list is 11 pages. A little over $15,000. Parts only.
So far the car runs great just a little rich at idle and very noisy. I have more motor than rear wheels. And it handles great on a tight road.
If it wasn't for this site, Cool Cats, and you guys my build would have been way more difficult. THANK YOU.













1987 Turbo Coupe, 306, Trick Flow Track Heat heads, Comp Cam, Trick Flow Pistons, Eagle Rods, Center Force clutch, T-5, 8.8 w/373 gears, and a bunch more

Re: Changing a A9L to Mega Squirt

Reply #6
If you haven't had it tuned how do you know it's rich at idle? A EEC-IV car with no catalytic converters is going to smell at idle. As long as you're not getting a rich code from the EEC it can keep everything in trim. Don't go by smell, go by what the EEC is telling you.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

Re: Changing a A9L to Mega Squirt

Reply #7
...

The downside to the A9L is it can be hard to tune because of the complexity of the strategy. Megasquirt is much easier to tune because it doesn't have all of the emissions or complicated edge case drivability dependencies. Holley is easier than Megasquirt.

Cougar 5.0 went Holley, but his exact route requires putting in a carb intake and a full re-wire. (Correct me if I'm wrong!)
Holley has other options, but I'm not super familiar.

Personally, if you aren't interesting into dumping a bunch of labor/$ into your car, I'd try and find a shop (even if it's down the road a bit) and tune your current A9L as you're N/A and don't have an extreme setup.

I used a carb-style Edelbrock SuperVic with the injector bungs because there are few choices in feeding a 427w to 600HP that will also fit under a stock hood.

I initially tuned the 427W using the A9L for break in and until I had all the Holley stuff gathered (I bought it used and a piece at a time cuz I'm a cheap . I even made the main power and a couple other cables myself. I did save $1000 tho :) ) With the A9L, I couldn't tune out some bad surging below 2000 RPM caused by the larger cam I'm using. I tried a few tricks that helped a little, but I just couldn't solve it. Been tuning for over a decade with the TwEECer, so it wasn't for lack of experience; as noted it was just too complicated.

The Holley does replace the engine harness, which after 30+ years was kind of nice actually. The new wiring is nice looking and no more Salt & Pepper shakers to deal with. Also, since the Holley logs many parameters by default, I could remove a ton of patch wiring for sensor logging including an old Innovate LM-1 wideband and DataQ acquisition module, USB hub etc. A mess feeding my glove box that I'll never have to worry about again. Fortunately, Ford has separate sensors/cabling for the dash gauges, so nothing lost other than the trip computer which used a feed from the Ford ECU.

Because the Holley uses full time wideband feedback, not only will it learn and get the fuel dialed in (using one of their base tunes as a starter), but with a bigger cam diluting the mixture at low RPMs, a secret I learned is to enrich the mixture there to ride out the lower RPM surging. Difficult to impossible to do with A9L, so it's been a worthwhile effort for me.

Holley this year released a Terminator X unit which is much less expensive than the HP/Dominator units.

Now, for a mild setup as per this thread, a Moates Quarterhorse or TwEECer can be used, or just a properly calibrated MAF as noted above.
11.96 @ 118 MPH old 306 KB; 428W coming soon.

Re: Changing a A9L to Mega Squirt

Reply #8
So the A9L in my Coupe is controlling a 331 making 468 fwhp with an SCT chip and of course a professional dyno tune.  I trailered the car and drove from Tulsa, OK down to McKinney, TX (four hours), spent the night at a hotel, was at the tuner for six hours, and then drove home another four hours.  There are zero reputable EEC-IV tuners in OK but there are a handful in Texas and this guy had several hundred customer reviews.  I called and he took time out of his very busy day and we talked about the build and my almost reached goal of 400 rwhp.  He called it and said it might get north of 350 rwhp.  Gave me a couple of suggestions (different MAF and larger exhaust) that might get me up towards 375 rwhp.  Running a full 2-1/2" exhaust now with a torque arm and panhard bar so no larger exhaust is in my future.  The MAF is off of a 2001 Mustang GT (80mm) and he suggested going to a 2000-2004 F150 Lightning MAF ($150) as I was running out of air up top i.e. pegging the meter.  I asked about the TB as its a 70mm and he said that was not the issue but if I wanted to the Edelbrock Performer RPM II upper could be massaged at the TB connection and that might also help.  I need to check fit up there.  If I end up going to the 90mm MAF then I will have to also rework the piping from the filter to the MAF and MAF to the TB.

Anyhow, the EEC-IV A9L can be tuned but it does have its limits like the guys are saying due to its complexity.  From what I understand and it makes sense due to technological advances the MegaSquirt's processor is way faster than the EEC-IV's.  You do not need a wide band O2 but it does help with tuning for sure.

So if you do not have the A9L then plan on around $200 for one if you have the luxury of being patient and hunting one down on the cheap.  If you are not mass air then you will need a mass air conversion kit which are around $50.  Then you will need a mass air meter which will cost different depending on what you get.  My 2001 Mustang GT MAF was $50 and the 6-pin pigtail (wiring harness) for it was like $15 and then you eliminate the two outer wires and wire the other four into the stock harness.  This meter absolutely requires a tune as the tables are nothing like what is preprogrammed into the A9L.  The SCT chip is around $225 and typically a tune will sell you the chip and a tune for $500.  So if you do it yourself and from scratch you are looking at $715 but with all that a good tuner can take a mild combo and make it all play nice.

83 351W TKO'd T-Bird on the bottle


93 331 Mustang Coupe - 368 rwhp

Re: Changing a A9L to Mega Squirt

Reply #9
The list below is what I've done to the car. I'm a novice compared to you guys. Sounds like you guys have done way more to your cars than I have. I was kind of working on a budget but I'm sure you know how that goes. The only outside labor was the machine shop on the block and balancing. Won't know what the horsepower is until I get it tuned. I know it won't be close to what you guys are running. Aerocoupe it looks like I've got a similar problem with tuning. Looks like I will have to trailer the car over to Los Angeles for dyno and tuning. Can't get any recommendations here in Southern Nevada. Cougar 5.0 I'm using my stock wiring harness with no problems- yet but after the first of the year I'm ordering a new harness, from engine and MAF to the computer, from Ron Francis. I know, in the future, I will have wiring problems. Removing the ABS wiring helped a lot so I only have the engine wiring at the firewall.
With the changes to the suspension, custom, boxed frame connectors, 14-1 rack, CHE upper and lower control arms, Borgeson steering shaft, car handles great. So far I have no idle problems, stalling, no check engine light, soft codes. Car has 2100 miles on it since the rebuild. God knows I've spent enough time banging my head on the work bench.

Stock 5.0 block, 0.030
Stock crank, polished, 0.010
ARP main bolts
Trick Flow Track Heat aluminum heads
Ford Racing Graphite Head Gaskets
ARP 7/16 in. Head Studs w/ Trick Flow Head Bolt Bushings
Trick Flow Forged Pistons, 4.030 in., flat top w/ 2 valve reliefs, 10-1
Summit Racing Moly Piston Rings
Eagle SIR I-Beam Connecting Rods, forged, shot peened
   ARP 3/8 in. rod bolts
COMP Cams Extreme Energy Cam and Lifter Kit
   Operating Range 1600 to 5600 rpm
   Intake Duration @ 0.50- 216
   Exhaust Duration @ 0.50- 224
   Adv. Intake Duration- 266
   Adv. Exhaust Duration- 274
   Intake Valve Lift- 0.544 in.
   Exhaust Valve Lift- 0.555 in.
   Lobe Separation- 112
   Grind # XE266HR
   Computer Compatible
COMP Cams Die Cast Aluminum Rocker Arms
   Full Roller, 1.6
   ARP Stud Size- 7/16 in., w/ polylocks
Trick Flow Chrome Moly 5/16 x 6.75 Push Rods
PRO SPORT Billet Damper, 50 oz, SFI
Roll Master Dual Timing Chain, billet steel gears, nitride coated, ISWIS chain
Ford Racing Billet Flywheel
    157 tooth, 50 oz, SFI, ARP bolts
Centerforce II clutch, pressure plate
Ford GT 40 upper and lower intake, ported
BBK 70mm Throttle Body, EGR Spacer
BBK Fuel Rails
Kirban Adj. Fuel Pressure Regulator, fuel pressure- 42lbs
Bosch 30lb fuel injectors
Walbro 255 lph fuel pump
BBK Cold Air System, Through Fender
Pro M 75mm MAF, calibrated for 30lb injectors, cold air
Stock A9l Computer
Timing- 14*
Idle- 850 rpm
BBK Equal Length Shortie Headers
2 ½ Exhaust, BBK “H” Pipe, Flowmaster 40 lers
T-5 w/ 335 1st, 0.68 5th
8.8 w/ 373, 2200 rpm @ 70mph
1987 Turbo Coupe, 306, Trick Flow Track Heat heads, Comp Cam, Trick Flow Pistons, Eagle Rods, Center Force clutch, T-5, 8.8 w/373 gears, and a bunch more

Re: Changing a A9L to Mega Squirt

Reply #10
Your engine modifications are very similar to mine. If it's running fine then you're good. A tune will probably pick up a couple of horsepower but you're not hurting anything driving it as is. As I said before I've been driving mine around for years with nothing but a calibrated MAF, timing, and idle adjustments.

No need to rush into getting it tuned. Closest guy to me who tunes EEC-IV stuff is about an hour and a half drive. Cost for a tune is about $500. Lazy/cheap ass me hasn't driven out there yet. One day I will.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

Re: Changing a A9L to Mega Squirt

Reply #11
Thanks for the help Thunderjet. I would like to get it tuned just to see what it has. Like I said the car runs great, instant start, no lag or stalling, plenty of power. No tuners here in Las Vegas. I'll have to trailer it to LA, 4 hrs away.
1987 Turbo Coupe, 306, Trick Flow Track Heat heads, Comp Cam, Trick Flow Pistons, Eagle Rods, Center Force clutch, T-5, 8.8 w/373 gears, and a bunch more

Re: Changing a A9L to Mega Squirt

Reply #12
An option I don't see discussed much here, but has a lot of success, is the PIMP system by Stinger Performance. Essentially, it's a Megasquirt setup that plugs directly into you factory harness, and mounts in the factory location. It can be set up as batch fire, or fully sequential. You can also go with coil packs and all kinds of various options. It's not a cheap solution, but it works very well and he has had some very fast and reliable cars use.
It's Gumby's fault.

Re: Changing a A9L to Mega Squirt

Reply #13
Exactly........

https://www.stinger-performance.com/store/pimpxs-engine-management
88 sport,TW heads, comp xe270hr, cobra u/Tmoss ported lower, 65 mm throttle body, under drives,smog delete,
1.7 roller rockers, cai, k&n, bbk adj regulator, 76mm Pro-m,all MSD ign. MSD dist,18° base timing, 3g alt.1 5/8 ceramic headers, 255lph walbro, 2.5" h-pipe, flowmasters, silverfox valvebody, 3.73 gear,
http://i216.photobucket.com/albums/cc154/flipnbird/DSCF0185.jpg ( RIP : ( )

Re: Changing a A9L to Mega Squirt

Reply #14
A Plug-in Microsquirt Powered (PiMP) is definitely an option, but for $850 plus the price of tuning it I think you'd be better off getting a competent person to tune the EEC-IV.