Need Help From people who know

i seen several on ebay motors today for very resonable prices.the ones i saw were for 88models but should be the same if you are stll speed density

get a mass air meter,computer from 90 and up and go.i personally would get a a9p automatic ecm.this ecm has more built in timing for the aod to compensate for lack of power through the drivetrain,they tend to make a 5 spd run better than an a9l ecm

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)

Computers from 89-92 are all the same. Look for the A9L sticker on the back cover for a 5 speed that matches your requirements. Example: E9ZF 12A650 AA" with the A9L code.

MASS air conversion instructions from http://www.stangnet.com/tech/maf/massairconversion.html 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
Conversion Harness kits & parts
http://www.mass-air.com/
http://fordfuelinjection.com/index.php?p=54

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

A9L computers are 5 speed only
A9P computers are automatic, but will work with a 5 speed.