Engine How far can you go with an A9L (or other) factory computer?

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reddy351

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I have a 94 GT engine that I'm going to use the stock cam with some 1.7 rockers, a pair of AFR 185 Enforcers and an Explorer manifold. What would I need to do to make these work with an A9L computer? I really don't plan on adding any other performance stuff in the future or I'd take the steep learning curve on a MegaSquirt. (I really don't want to do that.)

My plan is to get a Painless harness and A9L for the swap as I'm not running it in a Mustang. The reason for using the stock cam is to keep a stock-ish idle, which I prefer and the heads are there for the slight performance improvement AND the saved 40# off the front of the car.

This is not the typical "bigger is better" combo. Just a nice, reliable/tractable combo that I can enjoy driving every day.
 
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General karthief

wonder how much it would cost to ship you a pair
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Stock computer (A9L) will be just fine with that combo, the important thing, more so since this is a swap to another body/chassis is to duplicate the computer grounds in the harness like it was going into a mustang.
Do not 'stack' the grounds together in one place. They are separated for a reason (although I couldn't tell you why, maybe something about 'feed back'?)
This opinion is based on threads of problems I've read about here during the couple minutes I've been a member here and not based on any real mechanical experience :rolleyes:
 
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nickyb

WAIT,you now have a pair?
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If your dead set on using that exploder intake then don't waste your money on the afr185's.
That intake will choke down the heads.I
This is based on my own research, feel free to Do as you please.
 

96pushrod

I think they're a little easier to get off
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By the time you buy a harness and a9l, you pretty much could just get a terminator x - as it comes with a harness. If you already have all the stuff you listed then it doesn’t really matter I suppose.

Not that it won’t work with a a9l, but they’re almost all going to be at least 30 years old at this point.
 

reddy351

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If your dead set on using that exploder intake then don't waste your money on the afr185's.
That intake will choke down the heads.I
This is based on my own research, feel free to Do as you please.


Do you suggest I spend $800 on an aftermarket one that will do a tiny bit better than the Explorer? The Explorer is way better than the stock GT intake, no?
 

General karthief

wonder how much it would cost to ship you a pair
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Budget build cruiser for car shows and schlep'n around town the explorer is fine, just don't expect much after about 5500rpms, if you're going for that extra humph to get your heart rate up pulling away in traffic pick a better cam and intake.
Stock cam, 1.7's and the explorer intake in a light body (you didn't say what you were putting it in?) makes for a spunky ride.
JMO
 

reddy351

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Because it's the combination of parts that you get the most from. Even if you boost it, you'll get more power from a larger intake with those heads.


Read my first post: "This is not the typical "bigger is better" combo. Just a nice, reliable/tractable combo that I can enjoy driving every day."

I doubt I will EVER boost it. If I do, I'll have a functioning system with a new harness to build on.
 

2000xp8

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To answer your first question, i've seen the stock a9l handle 650rwhp+. No chip, no tuning.
Is that the right way to go? Since this sounds like an engine swap and you would be buying a harness and computer anyway, i'd probably say no.
I'm a fan of just a stock a9l, but i don't think i would acquire an aftermarket harness, then a used ecu and install it all when you could buy a terminator X setup.

As for your combination of parts.
I'd be very surprised if it ran well.
You are basically buying the biggest set of heads and slapping them on a 302 with 302 supporting parts.
If this is your plan, save yourself a ton of money, buy some used gt40x or gt40y heads, have them valve jobbed and run them.
The results will be similar and you could just run the stock 94 harness and computer.
 

reddy351

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The AFR Enforcers are very close to the GT40x heads, from what I've seen. The "AFR185" are very different from the AFR185 Enforcer". The Enforcers (that I have) are an "as cast" head. The AFR185 are CNC ported. They are worlds apart, different.
 
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Noobz347

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Read my first post: "This is not the typical "bigger is better" combo. Just a nice, reliable/tractable combo that I can enjoy driving every day."

I doubt I will EVER boost it. If I do, I'll have a functioning system with a new harness to build on.
You read your first post. You can stack a scooter induction system if you like. :shrug: Nobody is telling you that you can't.

It just doesn't make much sense to run one of the larger/better-flowing heads on the car and then choke it down.

But hey... There's a dude on Youtube that runs a V8 through single-barrel Chinese lawn mower carb. He gets great fuel mileage. :nice:



Ah! Here it is:


View: https://www.youtube.com/watch?v=gmPtCmL-Ldw&ab_channel=ThunderHead289


:)
 
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reddy351

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I think you're getting a little too emotionally involved this project. I asked for an opinion. I got yours. I took it into consideration and will move forward based on that consideration. We may not agree but, no worries, we'll both be ok.

Thank you for getting involved in the conversation.
 

General karthief

wonder how much it would cost to ship you a pair
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I think you're getting a little too emotionally involved this project. I asked for an opinion. I got yours. I took it into consideration and will move forward based on that consideration. We may not agree but, no worries, we'll both be ok.

Thank you for getting involved in the conversation.
Just giving opinions and offering options, you do know you can't run those heads with stock pistons? That's what I gathered from their website anyway (if I read it correctly), like I stated in post #8, you also didn't say what this is going in or anything else about the build just the parts you plan on using for the engine which will be ok, good till about 5000 to 5500 rpms, the explorer intake is good for low end torque but the heads are for a little higher rpm, the stock cam even with the 1.7 rockers are, again, better suited for low end torque, it's a little miss matched. It will, like I said be ok for cruising around town but it will quickly run outta steam when the go peddle is applied.
We are giving you advice with what little info you're giving,
You had a thread back in Jan this about this combo.
 

Mustang5L5

Put lubricant all over the balls
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IIRC, the cam profiles are what messes with the (untuned) A9L the most, usually the idle quality. Depending on how radical you get determines how well the A9L can adapt without being tuned. I've seen the A9L run some pretty wild combos provided the cam is not too radical.

A9L tuning is getting a 2nd wind it seems, especially if you follow Leech Motorsports. With tuning, it seems this is not an issue.
 
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reddy351

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Just giving opinions and offering options, you do know you can't run those heads with stock pistons? That's what I gathered from their website anyway (if I read it correctly), like I stated in post #8, you also didn't say what this is going in or anything else about the build just the parts you plan on using for the engine which will be ok, good till about 5000 to 5500 rpms, the explorer intake is good for low end torque but the heads are for a little higher rpm, the stock cam even with the 1.7 rockers are, again, better suited for low end torque, it's a little miss matched. It will, like I said be ok for cruising around town but it will quickly run outta steam when the go peddle is applied.
We are giving you advice with what little info you're giving,
You had a thread back in Jan this about this combo.

I sure did have a thread. I needed a new thread because I was not going to use the A9L back then.

I haven't seen anywhere that says I can't use these heads with stock pistons. (Mine isn't a 1986.) It's a cheap China casting with decent hardware, made to bolt onto a stock bottom end. Not sure why every write up would fail to mention needing to swap pistons.

Since you've read the installation manual, you'll know that these are designed for use UP TO 6000 rpm. Well within the parameters of 1) my needs and 2) the other hard parts in the system.

The Explorer intake flows around 200cfm. These heads at .500 lift flow 255cfm. My stock cam is definitely going to be the "bottleneck" in this combo and then the intake. And I'm good with that.
 
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reddy351

5 Year Member
Jun 13, 2006
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Columbus, Ohio
IIRC, the cam profiles are what messes with the (untuned) A9L the most, usually the idle quality. Depending on how radical you get determines how well the A9L can adapt without being tuned. I've seen the A9L run some pretty wild combos provided the cam is not too radical.

A9L tuning is getting a 2nd wind it seems, especially if you follow Leech Motorsports. With tuning, it seems this is not an issue.

It is funny how 20 years later, here we go again. Lol.

Once this is up and running with a NEW harness, if I decide to go bigger someday, I'll go the MegaSquirt "Plug and Play" route and do the cam and intake as well. At that point, everything in the engine management will be new.
 
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KRUISR

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Apr 16, 2015
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you also didn't say what this is going in
Agreed, but I am not sure it matters.

Lets read between the lines and the picture

My plan is to get a Painless harness and A9L for the swap as I'm not running it in a Mustang.
So none Mustang - so stand alone harness and computer.

And from his picture I would guess a Merkur XR4Ti with a 5 speed (A9L not P).


My opinion, cam will fall off before the intake does. Should have good street manners and be easy to cruise around with. Should make 300-350 at the crank (assuming electric fans). Sounds fun.
 
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