Bill USN-1
F.I. Moderator
We are referring to the 88-91 GM TBI-throttle body injection systems. The primary system being from a truck, van, or astro van with 4.3 or larger engines and using the 1227747 ECM. If you do get the 4.3 v-6 ECM, you will need to replace both chips in it with the v-8 chips. The v8 limphome/netres chip/calpack is marked 16060837. Order part number 16060836.
The v6 netres part number is 16051637.
The number on the chip that I had is 1 number different due to it being sold in the plastic carrier!!!
Use,
GM parts, GM parts online, Chevy parts, new GM parts
Or
GM auto parts at wholesale
Or
GM parts direct: your direct source for genuine GM parts
GM part # 16060836
category: emission control system hardware
pack qty: 1 core charge: $0.00
GM list: $21.07
our price: $10.54
Description: calibrati
you May find some 87's and some 92's with the same system so look close.
As a secondary you can use the 1228746 computer from the cars but will require an iat sensor and a different chip than the 7747.
If you are pulling the system yourself then pull everything off the motor that the harness is attached to! You can throw the unneeded parts away later.
Basic system:
1. Computer- better known as the ECM-engine control module. 1227747 or 1228746 you will need someone to program a chip for you to optimize the computer to your engine.
If you don't know what engine your computer came from, see the attached file below.
You will need the 3 or 4 letter bcc-broad cast code.
2. Throttle body- tb- the 4.3, 5.0 and 5.7 tb's are all the same cfm with 1 11/16" bores. The injectors are different sizes.
The 454 is larger with 2" bores.
I would recommend a tb from about the same size engine or larger. 304/345 use 5.0/5.7. If you run a cam/springs and headers then maybe the 454 tb. 392 can use the 350 or 454 tb.
Our motors turn so slow that you can actually tune a 345 to the 305 system.
Here's where to look for the part number.
Injector sizes-
color code black/white
engine 2.8l
flow lbs/hr @ 13psi 33
TBI bore 35mm
GM part # 5235430
color code yellow/blue
engine 4.3l
flow lbs/hr @ 13psi 45
TBI bore 43mm
GM part # 5235203
color code green/white
engine 5.0l
flow lbs/hr @ 13psi 40
TBI bore 43mm
GM part # 5235279
color code orange/black
engine 5.7l pu
flow lbs/hr @ 13psi 61
TBI bore 43mm
GM part # 5235206
color code yellow/brown
engine 5.7l copcar
flow lbs/hr @ 13psi 65
TBI bore 43mm
GM part # 17084327
color code blue/black
engine late bb pu
flow lbs/hr @ 13psi 80
TBI bore 51mm
GM part # 1708430
color code d red/d blue
engine early bb pu
flow lbs/hr @ 13psi 90
TBI bore 51mm
GM part # 5235231
3. Wire harness-pull from any donor vehicle above. It will need to be modified to fit your application.
4. Temp sender-cts pull from donor or buy new.
5. O2-oxygen sensor- you could pull from donor but a new one is cheap. 1 wire sensor will work fine. The universals just splice onto the wire from the harness.
For headers I recommend a 3 or 4 wire sensor. They have a built in heater to keep the sensor hot when it is mounted down in the collector.
To mount the o2 sensor you can buy the regular o2 bung or it they are not avail I use the 18mm sparkplug antifouler cut in half.
Summit racing
sum-g2990 $4.88
Motormite spark plug non-fouler: help!®; 18mm gasket seat; 2 per package 42009
The v6 netres part number is 16051637.
The number on the chip that I had is 1 number different due to it being sold in the plastic carrier!!!
Use,
GM parts, GM parts online, Chevy parts, new GM parts
Or
GM auto parts at wholesale
Or
GM parts direct: your direct source for genuine GM parts
GM part # 16060836
category: emission control system hardware
pack qty: 1 core charge: $0.00
GM list: $21.07
our price: $10.54
Description: calibrati
you May find some 87's and some 92's with the same system so look close.
As a secondary you can use the 1228746 computer from the cars but will require an iat sensor and a different chip than the 7747.
If you are pulling the system yourself then pull everything off the motor that the harness is attached to! You can throw the unneeded parts away later.
Basic system:
1. Computer- better known as the ECM-engine control module. 1227747 or 1228746 you will need someone to program a chip for you to optimize the computer to your engine.
If you don't know what engine your computer came from, see the attached file below.
You will need the 3 or 4 letter bcc-broad cast code.
2. Throttle body- tb- the 4.3, 5.0 and 5.7 tb's are all the same cfm with 1 11/16" bores. The injectors are different sizes.
The 454 is larger with 2" bores.
I would recommend a tb from about the same size engine or larger. 304/345 use 5.0/5.7. If you run a cam/springs and headers then maybe the 454 tb. 392 can use the 350 or 454 tb.
Our motors turn so slow that you can actually tune a 345 to the 305 system.
Here's where to look for the part number.
Injector sizes-
color code black/white
engine 2.8l
flow lbs/hr @ 13psi 33
TBI bore 35mm
GM part # 5235430
color code yellow/blue
engine 4.3l
flow lbs/hr @ 13psi 45
TBI bore 43mm
GM part # 5235203
color code green/white
engine 5.0l
flow lbs/hr @ 13psi 40
TBI bore 43mm
GM part # 5235279
color code orange/black
engine 5.7l pu
flow lbs/hr @ 13psi 61
TBI bore 43mm
GM part # 5235206
color code yellow/brown
engine 5.7l copcar
flow lbs/hr @ 13psi 65
TBI bore 43mm
GM part # 17084327
color code blue/black
engine late bb pu
flow lbs/hr @ 13psi 80
TBI bore 51mm
GM part # 1708430
color code d red/d blue
engine early bb pu
flow lbs/hr @ 13psi 90
TBI bore 51mm
GM part # 5235231
3. Wire harness-pull from any donor vehicle above. It will need to be modified to fit your application.
4. Temp sender-cts pull from donor or buy new.
coolant sensor approximate resistance specifications:
177 ohms @ 212 deg. F. Or 100 deg. C.
241 ohms @ 194 deg. F. Or 90 deg. C.
332 ohms @ 176 deg. F. Or 80 deg. C.
467 ohms @ 158 deg. F. Or 70 deg. C.
667 ohms @ 140 deg. F. Or 60 deg. C.
973 ohms @ 122 deg. F. Or 50 deg. C.
1188 ohms @ 113 deg. F. Or45 deg. C.
1459 ohms @ 104 deg. F. Or 40 deg. C.
1802 ohms @ 95 deg. F. Or 35 deg. C.
2238 ohms @ 86 deg. F. Or 30 deg. C.
2796 ohms @ 77 deg. F. Or 25 deg. C.
3520 ohms @ 68 deg. F. Or 20 deg. C.
4450 ohms @ 59 deg. F. Or 15 deg. C.
5670 ohms @ 50 deg. F. Or 10 deg. C.
7280 ohms @ 41 deg. F. Or 5 deg. C.
9420 ohms @ 32 deg. F. Or 0 deg. C.
12300 ohms @ 23 deg. F. Or -5 deg. C.
16180 ohms @ 14 deg. F. Or -10 deg. C.
21450 ohms @ 5 deg. F. Or -15 deg. C.
28680 ohms @ -4 deg. F. Or -20 deg. C.
52700 ohms @ -22 deg. F. Or -30 deg. C.
100700 ohms @ -40 deg. F. Or - 40 deg. C.
5. O2-oxygen sensor- you could pull from donor but a new one is cheap. 1 wire sensor will work fine. The universals just splice onto the wire from the harness.
For headers I recommend a 3 or 4 wire sensor. They have a built in heater to keep the sensor hot when it is mounted down in the collector.
To mount the o2 sensor you can buy the regular o2 bung or it they are not avail I use the 18mm sparkplug antifouler cut in half.
Summit racing
sum-g2990 $4.88
Motormite spark plug non-fouler: help!®; 18mm gasket seat; 2 per package 42009
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