Little help cant keep new engine running

Without a Mass Air Conversion, you will have a very difficult time getting it to run right. Ford Speed Density systems do not handle major changes in airflow or vacuum like a cam or heads.

The Mass Air conversion isn't that hard, it just takes some time and care in moving the pins and making the connections.

MASS air conversion instructions from Mustang Mass Air Conversion | StangNet FREE
A9L (5 Speed) computer from junkyard $100-$150
A9P (Auto or in a pinch, 5 Speed) computer from junkyard $100-$150
70MM MAF from 94-95 Mustang GT - $40-$70
MASS Air wiring harness kit $30-$85

The whole thing is probably less than $300 using junkyard parts.

The conversion harness seems to work well for most folks. It avoids the compatibility problems in using a harness from the junkyard. Simple and cheap, it is actually less work that swapping the wiring harness. I have pulled the stock harness out of a wrecked car and it was like wrestling a big python.

Conversion Harness kits & parts
Interactive Systems & Technologies Mass Air Home Page
Ford Fuel Injection EFI Harness Pigtails

If the idea of moving & soldering wires scares you, here's a list of compatible Mass Air wiring harnesses.

Copied from bbunt302
Just for reference, here's a list of all the compatible years:

89 harness should work for 86-89 as long as you're using mass air.
90 harness will only work in a 90. (B/c of air bags and dual dash connectors)
91 through early 92 harnesses should be compatible (single dash connector, fuel pump relay under driver's seat)
Late 92 through 93 harnesses should be compatible (single dash connector, fuel pump relay under the hood)

Larger MAF to go with Mass Air conversion:
94-95 Mustang GT MAF - $40-$100. It is 70 MM instead of the stock 55 MM on regular stangs built prior to 94. It uses a slip on duct on the side that goes to the throttle body and a 4 bolt flange on the other. You need a flange adapter to fit the stock slip on air ducting that goes to the air box. Wiring plugs right in with no changes. *1 *2

*1.) Metal flange adapter Kurtz Kustomz Motorsports, Inc. KKM Buy the TR70 for $44.95. Or spend some time on eBay looking for one that may fit.
Try AutoZone and ask for 81413 - Spectre / 3 in. Aluminum Intake Mass Air Flow Sensor Adapter at $12.00. You may have to order it online.

*2.) MAF & sensor interchange
The 94-95 Mustang 5.0 MAF & sensor is also found on:
1995-94 Mustang 3.8L F2VF-12B579-A2A,
1994-92 Crown Victoria 4.6L F2VF-12B579-A2A,
1995-94 Mustang, Mustang Cobra 5.0L F2VF-12B579-A2A,
1994-92 Town Car 4.6L F2VF-12B579-A2A,
1994-92 Grand Marquis 4.6L F2VF-12B579-A2A,
Evidently the –A1A, -A2A, AA, etc. on the end of the part number is a minor variant that did not change the operating specs. You should be able to ignore it and have everything work good.

cymmij said:

I basically understood the problem with speed density but I thought that having a custom made chip i would be ok. Should i just junk the chip and do a MAF conversion? I was intimidated because of the pin change outs and I am color blind and my electrical skills are only so so as it is and didnt wanna potentially make things worse.

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A Mass Air conversion is your best bet. Otherwise every time you make a change to the engine, you have to make a change to your custom chip. Mass Air accommodates all kinds of changes without needing to be reprogrammed.

Being color blind is a real handicap for this project. Check around the community colleges in your area for a student who is either in the automotive classes or electronic classes. Recruit him (or her) with a suitable bribe to help you.