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looking to change heads and cam, do i need to convert to MAF?

  • Thread starter Thread starter gritchy5.0
  • Start date Start date Jul 25, 2010

gritchy5.0

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Jul 17, 2010
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Rock Island IL
Jul 25, 2010
#1
  • Jul 25, 2010
  • #1
I have a 87 lx with basic bolt on stuff, this winter its getting a over haul and i was wondering if i put a b303 and some ported e7s on it am i going to need to convert to MAF?
 

jrichker

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#2
  • Jul 25, 2010
  • #2
When you change things that alter vacuum and airflow like heads and cam, you should also plan on changing over to Mass Air. You may get by without doing it, but the next thing you change will probably make things run poorly.
 

gritchy5.0

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Jul 17, 2010
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Jul 26, 2010
#3
  • Jul 26, 2010
  • #3
How hard is the conversion? im new to the fuel injection side of engine building. is this a plug and play thing or what does it involve?
 

notchback

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Jul 26, 2010
#4
  • Jul 26, 2010
  • #4
it's super basic. you swap out everything for the mass air stuff. computer , air tube, meter etc.
 

jrichker

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  • Jul 26, 2010
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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.

A Also see Ford Fuel Injection for help with the harness parts RJM Injection Tech Pigtails:, and connector pins, RJM Injection Tech Ford Terminals:
 

Cobra912

Active Member
May 1, 2005
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Jul 27, 2010
#6
  • Jul 27, 2010
  • #6
I bought a conversion harness and A9L cpu for 100 bucks on Ebay. Mass air meters are cheap too and will depend on what injectors you are going to run. If you are gonna do the HCI swap you definetly need to do the mass air conversion.
 
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