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Converting to Mass air on 87 and VSS

  • Thread starter Thread starter KZGUNS
  • Start date Start date Oct 18, 2018

KZGUNS

I can swing up to 11”
5 Year Member
Jul 23, 2018
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chardon, Ohio
Oct 18, 2018
#1
  • Oct 18, 2018
  • #1
I'm getting all the stuff together to convert my 87 LX to mass air. My question is the VSS which mine doesn't have? I have what i believe is dealer cruise, the controls are not on the wheel but on the column. There is a speed sensor on the cable near the firewall but not like factory cruise cars where its at the end of the cable by trans. So I'm wondering how this gets wired up? Does anyone have the info on this part of the conversion?

Thanks,!
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,258
17,942
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Massachusetts
Oct 18, 2018
#2
  • Oct 18, 2018
  • #2
You have to add it. I did this to my '88 which also doesn't have factory cruise. I had dealer cruise as well..but I ripped that stuff out.

You'll need:
VSS sensor
Speedo cable for a VSS equipped car


Installation is pretty straightforward. Remove the old speedo cable and transfer the speedo gear to the VSS. Install VSS in trans, and then route the new speedo cable and hook that up. The wiring plug for the VSS is clipped to the transmission crossmember. Simply plug it in.

From there, now it's a typical MAF swap in which you need to find the two VSS wires in the drivers side kick panel, tap into them, and hook them into the ECU
 
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KZGUNS

I can swing up to 11”
5 Year Member
Jul 23, 2018
1,002
588
133
chardon, Ohio
Oct 18, 2018
#3
  • Oct 18, 2018
  • #3
Mustang5L5 said:
You have to add it. I did this to my '88 which also doesn't have factory cruise. I had dealer cruise as well..but I ripped that stuff out.

You'll need:
VSS sensor
Speedo cable for a VSS equipped car


Installation is pretty straightforward. Remove the old speedo cable and transfer the speedo gear to the VSS. Install VSS in trans, and then route the new speedo cable and hook that up. The wiring plug for the VSS is clipped to the transmission crossmember. Simply plug it in.

From there, now it's a typical MAF swap in which you need to find the two VSS wires in the drivers side kick panel, tap into them, and hook them into the ECU
Click to expand...

Ahhh so my car is already equipped with the vss wiring and is just attached to crossmember unused? That makes it easier.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,258
17,942
224
Massachusetts
Oct 18, 2018
#4
  • Oct 18, 2018
  • #4
Correct. But just like every other Speed Density car out there, the wiring doesn't run to the ECU, so you need to pick it up in the driver's kick panel and route it there.
 
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KZGUNS

I can swing up to 11”
5 Year Member
Jul 23, 2018
1,002
588
133
chardon, Ohio
Oct 18, 2018
#5
  • Oct 18, 2018
  • #5
Mustang5L5 said:
Correct. But just like every other Speed Density car out there, the wiring doesn't run to the ECU, so you need to pick it up in the driver's kick panel and route it there.
Click to expand...

Got it! I believe the harness i'm getting from Mass-air.com has those wires included.
Thanks again, everywhere i looked no one mentioned the plug was secured under the car. I'm sure once i got under there i would have seen it but just trying to get everything in order before i dive in.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,258
17,942
224
Massachusetts
Oct 18, 2018
#6
  • Oct 18, 2018
  • #6
I've never seen it mentioned either. Didn't find out myself until I got under the car.
 

KZGUNS

I can swing up to 11”
5 Year Member
Jul 23, 2018
1,002
588
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chardon, Ohio
Oct 18, 2018
#7
  • Oct 18, 2018
  • #7
Mustang5L5 said:
I've never seen it mentioned either. Didn't find out myself until I got under the car.
Click to expand...

So here’s what I got. These plugs seem to already be plugged into another plug.
 

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KZGUNS

I can swing up to 11”
5 Year Member
Jul 23, 2018
1,002
588
133
chardon, Ohio
Oct 18, 2018
#8
  • Oct 18, 2018
  • #8
On the side there’s this plug
 

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Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,258
17,942
224
Massachusetts
Oct 18, 2018
#9
  • Oct 18, 2018
  • #9
That's reverse lights. Don't see another little plug clipped to the crossmember?
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,258
17,942
224
Massachusetts
Oct 18, 2018
#10
  • Oct 18, 2018
  • #10
Here's the only pic when I did mine. Located drivers rear of trans. You can see the plastic clip the plug is inserted in that has the typical faded yellow Ford plug to stick it into a hole



Right side of x member...the small hole is where I'm 99% sure it was attached to on my car
 

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Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,258
17,942
224
Massachusetts
Oct 18, 2018
#11
  • Oct 18, 2018
  • #11
Thinking about it...it's possible I gave some bad info. My car is a late 88 so it has the o2 harness jumper that 87s and early 88s don't have.

Ford eventually started prewiring all '88s like a MAF car (minus the MAF wiring) and may have added the vss wiring at the same time they added the o2 jumper loop for the start circuit.

Long story short...you may not have the wiring. In that case, you just need to get the VsS pigtail from LMR or rockauto and run two wires to the ECU area
 
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KZGUNS

I can swing up to 11”
5 Year Member
Jul 23, 2018
1,002
588
133
chardon, Ohio
Oct 18, 2018
#12
  • Oct 18, 2018
  • #12
Mustang5L5 said:
Here's the only pic when I did mine. Located drivers rear of trans. You can see the plastic clip the plug is inserted in that has the typical faded yellow Ford plug to stick it into a hole



Right side of x member...the small hole is where I'm 99% sure it was attached to on my car
Click to expand...

Nothing that I can see. I wonder if 87 didn’t have that provision? That would be my luck. Not a huge deal since it’s only 2 wires to the ecu.
 

Blown88GT

Founding Member
Nov 13, 1999
2,283
524
164
Palm Beach Gardens, FL
Oct 18, 2018
#13
  • Oct 18, 2018
  • #13
KZGUNS said:
Got it! I believe the harness i'm getting from Mass-air.com has those wires included.
...
Click to expand...
Yes it does. Other than the Ford Mass Air Conversion, they are probably the original ones to supply the harness. Got mine from them.
I was able to tap into the VSS harness in the engine compartment in front of the brake booster next to the shock tower
http://mass-air.com/Products.htm

Mass-Air Harnesses - We've Sold More Than Anyone!!



IST has converted more cars to Mass-Air than anyone!! Over 20,000 harnesses and computer kits sold to date, with no end in sight!! If you want to convert a Speed Density engine to a Mass-Air engine, IST’s LOW-COST conversion harness is the answer. All harnesses designed for speed density Mustang, Thunderbird, Cougar, Mark VII, Crown Victoria, Grand Marquis, & Town Car. Will not work on trucks, see truck conversion kits. Why convert to Mass-Air in the first place?? Simple, on a totally stock car engine, you will generally pick up 2 - 3 MPG, along with much crisper throttle response. On modified engines, it's mandatory, since the stock Speed Density computer has a very small "window" of adjustment built in to handle those changes. Even if you have modified your stock engine and it still seems to run OK, you still are not getting the maximum benefit from all those expensive aftermarket parts you put on. Plus, you have the added benefit of cleaner emissions, since most Speed Density systems tend to run on the rich side. This true OEM-style and quality kit allows you to custom tailor the harness to the exact length you need. Plus you'll find competent, friendly, and FREE technical support is provided for all of our products. We'll work with you to try and solve any problem you may encounter!!

Part Number CH-8611-F, for OBD-I EEC-IV connectors (4 terminal oval)……....................................$39.95
Part Number CH-8612-F
, for OBD-II EEC-V connectors (4 or 6 terminal rectangular)…....…..........$49.95
Part Number OA-9666-F, (6-wire add-on kit if you are using the internal ACT sensor )....................$4.95
 
Last edited: Oct 18, 2018
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KZGUNS

I can swing up to 11”
5 Year Member
Jul 23, 2018
1,002
588
133
chardon, Ohio
Oct 18, 2018
#14
  • Oct 18, 2018
  • #14
Blown88GT said:
Yes it does. Other than the Ford Mass Air Conversion, they are probably the original ones to supply the harness. Got mine from them.
I was able to tap into the VSS harness in the engine compartment in front of the brake booster next to the shock tower
http://mass-air.com/Products.htm

Mass-Air Harnesses - We've Sold More Than Anyone!!



IST has converted more cars to Mass-Air than anyone!! Over 20,000 harnesses and computer kits sold to date, with no end in sight!! If you want to convert a Speed Density engine to a Mass-Air engine, IST’s LOW-COST conversion harness is the answer. All harnesses designed for speed density Mustang, Thunderbird, Cougar, Mark VII, Crown Victoria, Grand Marquis, & Town Car. Will not work on trucks, see truck conversion kits. Why convert to Mass-Air in the first place?? Simple, on a totally stock car engine, you will generally pick up 2 - 3 MPG, along with much crisper throttle response. On modified engines, it's mandatory, since the stock Speed Density computer has a very small "window" of adjustment built in to handle those changes. Even if you have modified your stock engine and it still seems to run OK, you still are not getting the maximum benefit from all those expensive aftermarket parts you put on. Plus, you have the added benefit of cleaner emissions, since most Speed Density systems tend to run on the rich side. This true OEM-style and quality kit allows you to custom tailor the harness to the exact length you need. Plus you'll find competent, friendly, and FREE technical support is provided for all of our products. We'll work with you to try and solve any problem you may encounter!!

Part Number CH-8611-F, for OBD-I EEC-IV connectors (4 terminal oval)……....................................$39.95
Part Number CH-8612-F
, for OBD-II EEC-V connectors (4 or 6 terminal rectangular)…....…..........$49.95
Part Number OA-9666-F, (6-wire add-on kit if you are using the internal ACT sensor )....................$4.95
Click to expand...

I think on my 87 I have to run them from the vss to the ecu. There doesn’t seem to be any vss wires on my car. Not a huge deal. Knowing is half the battle lol
 

Blown88GT

Founding Member
Nov 13, 1999
2,283
524
164
Palm Beach Gardens, FL
Oct 19, 2018
#15
  • Oct 19, 2018
  • #15
Vehicles with cruise control had the VSS, cruise won't work without it. All GT's had cruise control. When Ford went to mass air, they also use the VSS to control the idle when coasting.

'86's-'88's had no mass air, therefore no wires to ECU. Calif. '88's were mass air only.
 
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