MAF/MAP harness differences?
05-05-2017, 07:51 PM
#1
MAF/MAP harness differences?
My son is wanting to put a TPI system on his '87 El Camino, and found a deal on an unused Painless engine harness. We were intending to use a MAF, and more or less duplicate the TPI system on my IROC.
Turns out the harness is for a MAP system..hard to modify the harness for MAF? He already has nearly everything he needs to build a MAF system.
Turns out the harness is for a MAP system..hard to modify the harness for MAF? He already has nearly everything he needs to build a MAF system.
05-05-2017, 09:44 PM
#3
Supreme Member
Re: MAF/MAP harness differences?
The difference is literally two sensors. Pretty much all of the aftermarket harnesses are going to run off of a 90-92 (or whenever they switched to MAP) MAP ecu and tpi plenum. The Fast retro efi system Im going with in my '87 Iroc is a based off of a MAP system, but it has it's own ECU. You can use a MAF plenum all you need to add is the MAP sensor and run a vacuum hose to one of the ports on the passenger side of the plenum. The Factory MAF sensors are kind of pricey.
05-05-2017, 10:08 PM
#4
Re: MAF/MAP harness differences?
The difference is literally two sensors. Pretty much all of the aftermarket harnesses are going to run off of a 90-92 (or whenever they switched to MAP) MAP ecu and tpi plenum. The Fast retro efi system Im going with in my '87 Iroc is a based off of a MAP system, but it has it's own ECU. You can use a MAF plenum all you need to add is the MAP sensor and run a vacuum hose to one of the ports on the passenger side of the plenum. The Factory MAF sensors are kind of pricey.
05-06-2017, 12:24 AM
#5
Supreme Member
Re: MAF/MAP harness differences?
OK, so here are the questions I should have asked... What ecu do you have and how are you going to control the transmission? From where I'm sitting you have a few options depending on what ecu and trans combo you're going to run.
You can locate a factory harness from an 85-90 whatever fbody, or a corvette, that uses the maf system. If the trans isn't going to be controlled by the ecu then look for a manual harness or find an auto harness if it is.
If you don't have an ecu, use the Painless harness you have and find a map ecu that either controls the trans or not.
From what I've read you have to use a map style ecu with the painless harnesses and I would think trying to rewire the harness to work with a maf wouldn't be feasible.
The maf is going to be more accurate from what I've read, but the price difference of the sensors is nuts. A new map is around $50 on the high end compared to a maf at $150 on the low end.
If it was me I would find a factory fbody harness for an 87, or what ever year the tpi system is, and go with that route. Only reason I went the map route was because the self tuning efi system I installed required it. My factory harness was destroyed by mice and I went from a 305 to a vortec 350 and it was going to cost too much to have the car properly tuned.
You can locate a factory harness from an 85-90 whatever fbody, or a corvette, that uses the maf system. If the trans isn't going to be controlled by the ecu then look for a manual harness or find an auto harness if it is.
If you don't have an ecu, use the Painless harness you have and find a map ecu that either controls the trans or not.
From what I've read you have to use a map style ecu with the painless harnesses and I would think trying to rewire the harness to work with a maf wouldn't be feasible.
The maf is going to be more accurate from what I've read, but the price difference of the sensors is nuts. A new map is around $50 on the high end compared to a maf at $150 on the low end.
If it was me I would find a factory fbody harness for an 87, or what ever year the tpi system is, and go with that route. Only reason I went the map route was because the self tuning efi system I installed required it. My factory harness was destroyed by mice and I went from a 305 to a vortec 350 and it was going to cost too much to have the car properly tuned.
05-06-2017, 12:36 AM
#7
Supreme Member
Re: MAF/MAP harness differences?
OK so a 200r4 isn't computer controlled so he won't need that portion of the harness...
Trending Topics
05-06-2017, 06:50 AM
#9
Re: MAF/MAP harness differences?
That's what I'm hoping. I already have an ECM, and appropriate MEMCAL for an '88 305 TPI with automatic. Almost everything we needed to do this swap with a MAF setup is already purchased..and then my son realized he's bought the wrong harness.
05-06-2017, 07:55 AM
#10
Moderator
iTrader: (1)
Join Date: Mar 2002
Location: Chasing Electrons
Posts: 18,432
Likes: 0
Received 225 Likes
on
211 Posts
Car: check
Engine: check
Transmission: check
Re: MAF/MAP harness differences?
It would be better and easier to get a '86 - '89 f-body TPI harness.
To use the '90 - '92 speed density harness will need to re-pin the three ECM connectors into two (use the two black ones, look at the MAF ECM). Also requires adding a knock filter and doing something about the VSS.
The VSS is one difference between the Camaro and Firebirds. The Camaro stayed with the optical buffer mounted on the speedometer head while the Firebird ended up with a transmission mounted VSS and the 4-Out Buffer box.
Can get a feel for what is required here:
http://www.eecis.udel.edu/~davis/z28/ecm_swap_730/
http://www.eecis.udel.edu/~davis/z28/ECMs/86to92.txt
RBob.
To use the '90 - '92 speed density harness will need to re-pin the three ECM connectors into two (use the two black ones, look at the MAF ECM). Also requires adding a knock filter and doing something about the VSS.
The VSS is one difference between the Camaro and Firebirds. The Camaro stayed with the optical buffer mounted on the speedometer head while the Firebird ended up with a transmission mounted VSS and the 4-Out Buffer box.
Can get a feel for what is required here:
http://www.eecis.udel.edu/~davis/z28/ecm_swap_730/
http://www.eecis.udel.edu/~davis/z28/ECMs/86to92.txt
RBob.