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Topic: Auto V.S. Manual Computer Qs (Read 1112 times) previous topic - next topic

Auto V.S. Manual Computer Qs

Ive looked at the schematics, and from what I can tell, I can easily trick my Auto computer into working with the T-5. 

But sometimes I see postings on other sites that say "Only use the correct computer" or that the computer makes a big difference.

1. Can someone explain to me, aside from electrical, what differences there are in the computers? 

2. As long as I wire up the starting circuit correctly, why does it matter if I use an auto or manual computer?

3. Why is the A9L so sought after?

Thanks,
-dz

Auto V.S. Manual Computer Qs

Reply #1 –
I've used an A9P in my manual car for years, I did try a A9L and the a9p seemed to hold the rpms slightly while shifting gears, it had a very very small delay when the rpms came down. The A9L rpms always fell like a rock when off the throttle. Not sure if thats how they all are but the two EEC-IV I had behaved like that.

I'll speculate and say the A9P is setup like that to keep the car at a nice idle while in gear at a stop light?, or to make the car shift more smoothly with the AOD?

Also I think A9L are more popular among tuners of custom chips
[SIGPIC][/SIGPIC]

Auto V.S. Manual Computer Qs

Reply #2 –
Quote from: thunder306;202221
I've used an A9P in my manual car for years, I did try a A9L and the a9p seemed to hold the rpms slightly while shifting gears, it had a very very small delay when the rpms came down. The A9L rpms always fell like a rock when off the throttle. Not sure if thats how they all are but the two EEC-IV I had behaved like that.

I'll speculate and say the A9P is setup like that to keep the car at a nice idle while in gear at a stop light?, or to make the car shift more smoothly with the AOD?

Also I think A9L are more popular among tuners of custom chips

That is exactly it.  The Auto EEC's do that to keep the car from stalling when it comes to a stop.
One 88

Auto V.S. Manual Computer Qs

Reply #3 –
I was told the A9p will work with auto and manual,and the Speed Density DA1 will work with both as well.I use an A9p as well.
'88 Sport--T-5,MGW shifter,Trick Flow R intake,Ed Curtis cam,Trick Flow heads,Scorpion rockers,75mm Accufab t-body,3G,mini starter,Taurus fan,BBK long tube headers,O/R H-Pipe, Flowamaster Super 44's, deep and deeper Cobra R wheels, Mass Air and 24's,8.8 with 3.73's,140 mph speedo,Mach 1 chin spoiler,SN-95 springs,CHE control arms,aluminum drive shaft and a lot more..
 

Auto V.S. Manual Computer Qs

Reply #4 –
I was always told that you can use an automatic ecm with a manual, but not vice-versa. It probably doesn't matter too much either way though. I have an A9L in mine cause it's a manual.
Matt
1984 Thunderbird - 89 302 HO, GT40 heads w/ Trick Flow springs, E303 cam, Edelbrock Performer 289 intake and 600 cfm 4bbl, Mustang headers, Jegs o/r H pipe, Dynomax lers, Mustang AOD and shifter, Mustang 8.8 w/ 3.73s, 3G alternator, Mustang front and rear sway bars, KYB 87-88 Turbo Coupe shocks and struts, and 11" front brakes.

1988 Mustang GT - GT40 heads, Explorer intake, 70mm throttle body, 70mm MAF, Crane 1.7 rrs, E303 cam, Kirban Kwik shifter w/ Pro 5.0 deluxe handle, aluminum clutch quadrant and firewall adjuster, o/r h pipe, Dynomax lers, 3G alternator, aluminum radiator, and 3.27 gears.
 
1986 Cougar 5.0, 1989 Mark VII LSC 5 speed, 1980 Mercury Zephyr 4 door (sold)

Auto V.S. Manual Computer Qs

Reply #5 –
I really don't believe the comp. knows when your shifting.
The 9L can tollerate idle rpm better with "flucsuation"
I don't think thats a word! but whatever.
Old Grey Cat to this.88 Cat, 5.0 HO, CW mounts, mass air, CI custom cam, afr165's, Tmoss worked cobra intake, BBK shorty's,off road h pipe, magnaflow ex. T-5,spec stage 2 clutch, 8.8 373 TC trac loc, che ajustables with bullits on the rear. 11" brakes up front. +

Auto V.S. Manual Computer Qs

Reply #6 –
Quote from: 5.0 bird;202296
I was always told that you can use an automatic ecm with a manual, but not vice-versa.


i thought it was the other way around? autos have all that rotating mass to keep the engine revved up and full of momentum during a shift. if you put that comupter in a manual and push in the clutch the revs should drop alot further then u want them to. so basically, the manual feeds the engine a little more fuel during shifts.
1988 Thunderbird sport
2004 Ford F150 Lariat
2008  Chevrolet Cobalt Sport
2007 Suzuki DR-Z400S dual sport/Supermoto
1988 Thunderbird LX - sold
1988 Mercury Cougar XR-7 with GST kit - gone

Auto V.S. Manual Computer Qs

Reply #7 –
So,what's the bottom line?
'88 Sport--T-5,MGW shifter,Trick Flow R intake,Ed Curtis cam,Trick Flow heads,Scorpion rockers,75mm Accufab t-body,3G,mini starter,Taurus fan,BBK long tube headers,O/R H-Pipe, Flowamaster Super 44's, deep and deeper Cobra R wheels, Mass Air and 24's,8.8 with 3.73's,140 mph speedo,Mach 1 chin spoiler,SN-95 springs,CHE control arms,aluminum drive shaft and a lot more..

Auto V.S. Manual Computer Qs

Reply #8 –
I tried both in my 5 speed car. The auto computer seemed a little sluggish down low compared with the 5 speed computer. Fuel economy was unchanged and they both idled the same so I kept the L and sold the P. Might have turned out different if I had an auto tranny but I dont know.
[SIGPIC][/SIGPIC]
86 5.0 Turbocoupe (Katrina), 87 5.0 Sport (Rita)

Auto V.S. Manual Computer Qs

Reply #9 –
There really isn't much difference in either... BOTH will hold the RPMs up when coming to a stop(assuming you have a working speed sensor)...

I my Bird the A9L gives far better driveability without the 1500 RPM bucking I get with a A9P or C3W1... According to a tuner guy I know, the manual transmission EEC has a slightly richer curse mode, to eliminate bucking in the manual cars(which my mostly stock 5speed Stang did with the A9P)...