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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

aftermarket mass air conversion kits

  • Thread starter Thread starter diggy pits
  • Start date Start date Dec 19, 2009
D

diggy pits

New Member
Sep 4, 2009
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ARNOLD MO.
Dec 19, 2009
#1
  • Dec 19, 2009
  • #1
does anyone know if aftermarket mass air systems come with a new computer or do i still need to find one out of a 89, i have a 88 gt with speed density on a 347 stroker. it doesnt run right yet i know a mass air conversion is a must but 89 mustangs are not very plentiful in the junkyards. i hate to buy a 89 just for the mass air and i hate to get rid of my 88 body , its extremely solid for a missouri car not any rust. any help would be great.
 

TC93

Well-Known Member
Sep 11, 2000
2,075
1
57
Ellerslie GA 31807
Dec 19, 2009
#2
  • Dec 19, 2009
  • #2
They do make a jumper type hanress that can be added to you SD hanress. Not too bad to install, but does require taking the EEC 60 pin connector apart.. They usally sell for about $40.. I did a conversion liek that way back in the day(93), when harnesses were still about $350-400 around here. Did it to my 88 and never had a problem.....

mass air adapter harness..
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,249
17,932
224
Massachusetts
Dec 20, 2009
#3
  • Dec 20, 2009
  • #3
IST also makes a harness kit

Interactive Systems & Technologies Mass Air Home Page

It's a little more complete with the wiring for the fuel pump relay and VSS. If your '88 does not have cruise control, youwill need to add a VSS sensor and new speedo cable. If it has cruise, you are all set.

As for the computer, you can use any Mass Air computer. Doesn't need to be from an '89. If your car is a 5-spd, you can use one from either an AOD or a 5-spd. If your car is AOD (or originally was) you will need an AOD only comp unless you swap the O2 and Trans harness.

As for the meter, if you are running 19's (which i doubt you are) then you can use an 94-95 70mm MAF with an adapter fitting. Cheap, and supports some decent HP limits
 
J

jerryD

Founding Member
Mar 16, 2000
1,061
0
37
Gladstone, MO
Dec 20, 2009
#4
  • Dec 20, 2009
  • #4
if u are in the KC area, i'll help you convert it over for ya when you are ready.
 

scottmach

New Member
Oct 23, 2004
19
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0
East Haven CT.
Dec 20, 2009
#5
  • Dec 20, 2009
  • #5
A VSS may or may not be necesary. When I did a Mass Air Conversion my car didn't come with cruise and I didn't add the VSS and I never had any stalling issues.
 
D

diggy pits

New Member
Sep 4, 2009
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ARNOLD MO.
Dec 20, 2009
#6
  • Dec 20, 2009
  • #6
someone around here had told me that i needed a 89 for a true plug and play on my 88gt , they said that all i needed to do was pull the harness and computer out of a 89 aod and plug it up and go . but if any computer 89 -93 works thats even better news if get a aftermarket harness. thanx for the info
 
D

diggy pits

New Member
Sep 4, 2009
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ARNOLD MO.
Dec 20, 2009
#7
  • Dec 20, 2009
  • #7
thanks for the offer but im just outside of st. louis
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,249
17,932
224
Massachusetts
Dec 20, 2009
#8
  • Dec 20, 2009
  • #8
diggy pits said:
someone around here had told me that i needed a 89 for a true plug and play on my 88gt , they said that all i needed to do was pull the harness and computer out of a 89 aod and plug it up and go . but if any computer 89 -93 works thats even better news if get a aftermarket harness. thanx for the info
Click to expand...

If you want true plug and play, you need an entire 1989 engine harness, and parts of the '89 interior harness as there are a few wires missing to tie into the VSS and fuel relay. That's why the piggybank MAF harnesses just provide the additional harness.

You are right in your assumption that '89 harnesses are hard to find and most will want decent $$$ for one.

Any 89-93 comp works if you have a 5-spd. If you have aod you need to get an AOD comp.
 
M

MH-47gMECHANIC

New Member
Dec 19, 2009
5
0
0
Dec 20, 2009
#9
  • Dec 20, 2009
  • #9
Mustang5L5 said:
IST also makes a harness kit

Interactive Systems & Technologies Mass Air Home Page

It's a little more complete with the wiring for the fuel pump relay and VSS. If your '88 does not have cruise control, youwill need to add a VSS sensor and new speedo cable. If it has cruise, you are all set.

As for the computer, you can use any Mass Air computer. Doesn't need to be from an '89. If your car is a 5-spd, you can use one from either an AOD or a 5-spd. If your car is AOD (or originally was) you will need an AOD only comp unless you swap the O2 and Trans harness.

As for the meter, if you are running 19's (which i doubt you are) then you can use an 94-95 70mm MAF with an adapter fitting. Cheap, and supports some decent HP limits
Click to expand...


vss? what is that really and why would you need that if your car doesnt already have cruise control? how about just getting the mass air setup off a 89-93 stang with 5speed and NO CRUISE CONTROL and put it on an 87 with a 5speed and no cruise. would that work a little more details would be helpful.
 

liljoe07

5 Year Member
Feb 18, 2009
1,622
363
124
Cartersville,Ga
Dec 20, 2009
#10
  • Dec 20, 2009
  • #10
The VSS lets the computer know how fast you are going. Its sends a square wave signal to the ECM based on road speeds. Its a magnetic reluctance sensor. In a manual setup, if speeds above 6mph, the ECM uses the signal as part of the ISC( Idle speed control) strategy per the Ford GUFB. At speed below 6mph, the ECM uses the base idle settings along with spark timing. Its really an important sensor wether Cruise Control is an option or not.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,249
17,932
224
Massachusetts
Dec 21, 2009
#11
  • Dec 21, 2009
  • #11
MH-47gMECHANIC said:
vss? what is that really and why would you need that if your car doesnt already have cruise control? how about just getting the mass air setup off a 89-93 stang with 5speed and NO CRUISE CONTROL and put it on an 87 with a 5speed and no cruise. would that work a little more details would be helpful.
Click to expand...

The Vehicle Speed Sensor was only used on 86-88 Mustangs that had cruise as a way to let the computer know the speed of the car. If the Mustang did not have cruise control, there was no need for the sensor and Ford didn't put it on the car. I beleive 1988 was the only year that the wiring for the VSS was present making it a easy add on. 86 and 87 will need to run the wires to under the car.

1989+ (and cali 1988 MAF cars) got the VSS integrated into the MAF setup, so not it's a vital part of the system. Both cruise and non-cruise cars got the VSS.

The issue with not installing a VSS if you convert a non-cruise 86-88 to MAF is sometimes the car will stall when coming to a stop. The VSS usually tells the computer the car is stopping and the car reacts and doesn't stall out. Some cars can get away without the VSS, other's cannot.

To add a VSS, you need the sensor and a different speedo cable. Also, 86-87 cars will need to add the wiring to under the car. I beleive LRS sells the sensor,cable and wiring pigtail for the VSS.
 
M

MH-47gMECHANIC

New Member
Dec 19, 2009
5
0
0
Dec 21, 2009
#12
  • Dec 21, 2009
  • #12
wow seems like a big hassle to convert to mass air, maybe i will just convert to a carb. havent messed with a mustang since i sold my 89 seems like alot of stuff has been discontinued or is no longer available at summit, jegs or some of the other mustang performance shops. i think when i start messing with the stang again it will all come back to me but at this point just seems like a big hassle.. anyone near savannah georgia thats willing to help me out and relearn the foxbody again.
 

MY 85 GT

10 Year Member
Mar 7, 2008
1,852
208
104
New Jersey
Dec 21, 2009
#13
  • Dec 21, 2009
  • #13
Some good info here...
 

apollo12

New Member
Dec 11, 2007
155
0
0
port st.lucie fla
Dec 22, 2009
#14
  • Dec 22, 2009
  • #14
I have a 1989 5.0 harness if you need one pm sent
 
M

MH-47gMECHANIC

New Member
Dec 19, 2009
5
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0
Jan 31, 2010
#15
  • Jan 31, 2010
  • #15
i did not recieve that pm, could you send again
 
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