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A9l Questions

  • Thread starter Thread starter Yoyoda
  • Start date Start date Sep 18, 2014
Y

Yoyoda

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Mar 4, 2014
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Sep 18, 2014
#1
  • Sep 18, 2014
  • #1
I'm looking for a A9L for my fox 302/T5 swap and see Autozone has quite a few different ones listed. A mechanic friend of mine says I should get the one for a 5 sp convertible as it has a slightly more aggressive timing curve vs the hatch. I think it was timing he said. Anyways, a quick search on the WWW shows no info confirming this. Anyone know if it's fact or myth?
Thanks.
 

jrichker

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#2
  • Sep 18, 2014
  • #2
A9L computers are basically all the same. There may be some minor differences to accommodate the state emissions requirements, but nothing that I know of that affects performance. All the 5.0 Mustangs from 89-92 had the same HP and torque ratings.

Ford changed the way that they measured the HP in 93, but the engine was unchanged. That accounts for any differences in advertised HP when 89-92 models are compared to the 93 model 5.0 Mustang.
 

Micheal Nadeau

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Sep 18, 2014
#3
  • Sep 18, 2014
  • #3
An A9P has a more aggressive spark and fuel curve to compensate for the AOD trans. The HP numbers were measured on an engine dyno, not chassis dyno. The electronics were controlled by a standalone system, not each vehicles specific computer.

Your "friend" told you to get an A9L because that is a manual computer. You honestly wont feel a difference between the two.
 

mikestang63

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Aug 27, 2012
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Sep 18, 2014
#4
  • Sep 18, 2014
  • #4
You can use an A9P in a manual car, but cannot use an A9L in an AOD, as the A9P has spark and fuel parameters for an automatic trans when the car is sitting at idle, a stop light etc.
 

Mustang5L5

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#5
  • Sep 19, 2014
  • #5
The bigger question here is what harness are you using for the O2 sensors. Did you swap anything, or are you running the harness as is from when it was an automatic. That will dictate which computer to select. Your options really are A9L (manual) or A9P (auto). Other than that, convertible vs hatch doesn't matter.
 
Y

Yoyoda

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Sep 19, 2014
#6
  • Sep 19, 2014
  • #6
Sorry for the confusion. The swap is into a Miata. I didn't mention that as it is off topic and I've been asked to not post outside my build thread, but this is not really a question directly related to my swap.
My mechanic buddy mentioned the convertible(5sp) EEC was more aggressive than the hardtop 5sp version. Was just looking for confirmation.
Thanks all for the replies. Very helpful. I'll post an update on my build thread once I start tearing into it. Still gathering parts right now, but about 90% there.
 

Micheal Nadeau

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Sep 19, 2014
#7
  • Sep 19, 2014
  • #7
There is no differentiation between convertible, notch, or hatch when it comes to computers. It is designated by:
A9L - '89 - '92 Fed Manual
A9P - '89 - '92 Fed Automatic
A9S - '89 California Manual
A9T - '89 California Automatic
A3M - '93 Manual
A3M1 -
A3M2
D3D1
X3Z - '93 Cobra
C3W - '93 Automatic
C3W1
8LD - '88 California Manual
8LF - '88 California Automatic

The ones I left blank, I have no information on. Some here may be able to fill in. I may be missing a couple. Either way, notice the designation does not mention convertible, hatch or notch.
 
Reactions: fredfifty
Y

Yoyoda

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Sep 21, 2014
#8
  • Sep 21, 2014
  • #8
http://www.autozone.com/autozone/pa...p8?filterByKeyWord=computer&fromString=search

So, I'm looking to buy one of these. What is the difference between the second and third one on this page. They show the same specs. I see the convertable and the hardtop version are listed separately but share the same model #.
 

Micheal Nadeau

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Dec 30, 2013
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Sep 21, 2014
#9
  • Sep 21, 2014
  • #9
One is Federal Emmissions and the other is California Emmisions.
 
Y

Yoyoda

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#10
  • Sep 21, 2014
  • #10
But they both say federal emmissions.
 

Micheal Nadeau

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Dec 30, 2013
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Sep 21, 2014
#11
  • Sep 21, 2014
  • #11
The first two that come up are California Emission manual. The next one is Federal Emission automatic. The fourth one is Federal Emission manual. I'm not gonna beat around the bush here, you are reading into this whole hatch, notch and convertible labeling for no reason. If you are using this for a Miata, it doesn't matter what computer you use. Again, Ford never labeled the computer by vehicle type. Only year, transmission and either Federal or California.
 

Mustang5L5

That is…until I whipped out my Bissell
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Feb 18, 2001
43,177
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Sep 22, 2014
#12
  • Sep 22, 2014
  • #12
Yoyoda said:
but this is not really a question directly related to my swap.
Click to expand...

Actually, it sort of is.

The wiring harness you are using will dictate which EEC to run vs your desire to choose one.

So, i ask, what parts car did the wiring harness you are using come from? Auto or 5-spd?
 
Y

Yoyoda

Member
Mar 4, 2014
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Sep 22, 2014
#13
  • Sep 22, 2014
  • #13
OK, I'll have to do a screenshot of that Autozone page. I couldn't understand why you couldn't see what I was seeing but once I clicked that link on a different computer I see that the page comes up differently.
And yes, I do understand that the eec's are the same regardless of body style. Simply put, the answer to my original question is "myth".
Thanks again for the info. Now I know.
Cheers.
 
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