My 99+ f-body fuel pump install

Listed Curb weights

03 cobra vert - 3780
03 cobra coupe - 3665
00 camaro Z28 hard top - 3306
92 camaro Z28 hatchback - 3273
00 vette hardtop - 3173
92 GT hatchback - 3144
03 vette Z06 - 3116
92 LX 5.0 hatchback - 3010
04-06 GTOs - 3725
MKIV supras - 3505
Vipers - 3400

Random Part numbers

ASP pulley a/c belt f-body - K040378
ASP pulley accessory belt crank only GTO - K060750
ASP pulley a/c belt GTO - K040400
Fuel line plastic - 10409885
Clutch return spring f-body - 10278874
clutch slave f-body - 15046288
clutch master f-body - 12570277
ARP wheel studs f-body - 100-7708
long lugnuts - 7352142 napa
Spec Stage 4 F-pad - SCO94F
Spec billet flywheel - SC75S
97 vette fuel rail - 12556705
97 vette fuel rail regulator - 12554677
fuel hard lines f-body – 10424769
97 vette braided fuel line - 10279630
Camaro switch blanks above radio - 10273932
Gates drivealign idler pulley (slightly larger diameter and with big edges to help with throwing belts) - 38009
2 Bar MAP sensor (20 kpa to 200 kpa) - 12580698 (new part #12615136)
3 Bar MAP sensor (old block style - 40 kpa to 300 kpa) - 12223861
3 BAR MAP sensor LS9/LSA/ZR1 - 12592525

Spark Plugs from hot to cold

NGK TR55 (stock #3951) - N/A only tapered seat
NGK TR6 (stock #4177) - N/A only or very small amount of N2O tapered seat
NGK BR7EFS (stock #1094) - resistor non-projected tapered seat
NGK B8EFS (stock #1049) & Autolite AR474 - non-resistor non-projected tapered seat
NGK B9EFS (stock #1085) & Autolite AR473/AR472 - non-resistor non-projected tapered seat

 

Injector Duty Cycle to Pulse Width
RPM – 80% – 90% – 100%
3000 32 ms 36 ms 40 ms
3500 27 ms 31 ms 34 ms
4000 24 ms 27 ms 30 ms
4500 21 ms 24 ms 27 ms
5000 19 ms 22 ms 24 ms
5500 17 ms 20 ms 22 ms
6000 16 ms 18 ms 20 ms
6500 15 ms 17 ms 18 ms
7000 14 ms 15 ms 17 ms
7500 13 ms 14 ms 16 ms
8000 12 ms 14 ms 15 ms

 

Delphi 5-Pin MAF
Connector Pins, left to right, looking into inlet
(Left)
1 IAT output, to F-Body IAT harness, TAN (tan), to PCM C2 Pin 25
2 IAT reference, to F-Body IAT harness, PPL (purple), to PCM C1 Pin 57
3 MAF ground, to FBody MAF harness, BLK (black) to main ground dist.
4 MAF power (IGN), to FBody MAF harness, PNK (pink) to ENG SEN fuse
5 MAF output, to FBody MAF harness, YEL (yellow) to PCM C2 Pin 31 (Right)

’98-’02 3-pin MAF
Connector Pins, left to right, looking into inlet
(Left)
1 MAF output, to FBody MAF harness, YEL (yellow) to PCM C2 Pin 31
2 MAF ground, to FBody MAF harness, BLK (black) to main ground dist.
3 MAF power (IGN), to FBody MAF harness, PNK (pink) to ENG SEN fuse (Right)

 

Oil viscosity

T(C)  M1 0W40 * GC 0W30 * M1 0W30 * M1 5W30 * M1 10W30 * M1 0W20 * RL 5W20

-20   2661.5    2609.0    1994.8    2225.1    3424.8     1712.7    2995.8

-10   1197.8    1127.1     872.4     944.7    1332.9      730.8    1165.3

0      599.3     546.6     428.3     452.9     595.7      352.8     521.4

10     327.6     291.8     231.3     240.1     298.3      188.5     261.8

20     192.9     168.8     135.3     138.3     164.1      109.5     144.5

30     121.0     104.4      84.6      85.5      97.6       68.3      86.3

40      80.0      68.4      56.0      56.0      62.0       45.1      55.0

50      55.4      47.0      38.8      38.5      41.6       31.3      37.0

60      39.8      33.7      28.1      27.7      29.2       22.6      26.1

70      29.7      25.0      21.0      20.6      21.4       17.0      19.2

80      22.7      19.1      16.2      15.8      16.1       13.1      14.5

90      17.8      15.0      12.8      12.4      12.5       10.4      11.3

100     14.3      12.0      10.3      10.0      10.0        8.4       9.1

110     11.7       9.8       8.5       8.2       8.1        6.9       7.4

120      9.8       8.2       7.1       6.9       6.7        5.8       6.1

130      8.2       6.9       6.0       5.8       5.7        5.0       5.2

140      7.0       5.9       5.2       5.0       4.9        4.3       4.4

150      6.1       5.1       4.5       4.3       4.2        3.7       3.9

HTHS     3.6       3.6       3.0       3.1       3.2        2.6       3.3

 

These CR numbers are with the stock GM 5.7L displacement LS1 graphite head gaskets installed.
Installing the thicker 2003 GM MLS head gaskets will decrease your compression ratio by approx 0.1 – 0.2
72.27cc = 9.1 CR
71.71cc = 9.2 CR
71.05cc = 9.3 CR
70.59cc = 9.4 CR
70.03cc = 9.5 CR
69.74cc = 9.6 CR
68.91cc = 9.7 CR
68.35cc = 9.8 CR
67.79cc = 9.9 CR
67.23cc = 10.0 CR
66.67cc = 10.1 CR (stock LS1 head spec)
66.11cc = 10.2 CR
65.55cc = 10.3 CR
64.99cc = 10.4 CR
64.43cc = 10.5 CR (stock LS6 head spec)
63.87cc = 10.6 CR
63.31cc = 10.7 CR
62.75cc = 10.8 CR
62.19cc = 10.9 CR
61.63cc = 11.0 CR
61.07cc = 11.1 CR
60.51cc = 11.2 CR
59.95cc = 11.3 CR
59.39cc = 11.4 CR
58.83cc = 11.5 CR
58.27cc = 11.6 CR

 

Casting Number 241 and 853
Head: 1997+ LS1 5.7 Liter Passenger Car
Material: Aluminum
Part Number: 12559853 (1997-98) and 12559853 (1999-00) and 12564241 (2001-03)
Combustion Chamber Volume: 66.67cc
Compression Ratio: 10.1:1
Intake Port Volume: 200cc
Exhaust Port Volume: 70cc
Intake Valve Diameter: 2.00 inches
Exhaust Valve Diameter: 1.55 inches

Casting Number 243
Head: 2001 LS6 5.7 Liter Passenger Car
Material: Aluminum
Part Number: 12564243
Combustion Chamber Volume: 64.45cc
Compression Ratio: 10.5:1
Intake Port Volume: 210cc
Exhaust Port Volume: 75cc
Intake Valve Diameter: 2.00 inches
Exhaust Valve Diameter: 1.55 inches

Casting Number 706 and 852
Head: 1999+ LR4 4.8 Liter Truck
1999+ LM4 /LM7 5.3 Liter Truck
Material: Aluminum
Part Number: 12559852 and 12561706
Combustion Chamber Volume: 61.15cc
Compression Ratio: 9.5:1
Intake Port Volume: 200cc
Exhaust Port Volume: 70cc
Intake Valve Diameter: 1.89 inches
Exhaust Valve Diameter: 1.55 inches

Casting Number 373
Head: 1999-2000 LQ4 6.0 Liter Truck
Material: Cast Iron
Part Number: 12561873
Combustion Chamber Volume: 71.06cc
Compression Ratio: 9.5:1
Intake Port Volume: 210cc
Exhaust Port Volume: 75cc
Intake Valve Diameter: 2.00 inches
Exhaust Valve Diameter: 1.55 inches

Casting Number 317 and 035
Head: 2001+ LQ4 6.0 Liter Truck
Material: Aluminum
Part Number: 12572035
Combustion Chamber Volume: 71.06cc
Compression Ratio: 10:1
Intake Port Volume: 210cc
Exhaust Port Volume: 75cc
Intake Valve Diameter: 2.00 inches
Exhaust Valve Diameter: 1.55 inches

 

IAT resistance/temperature

9420 ohms = 32 *F – 0 *C
7280 ohms = 41 *F – 5 *C
5670 ohms = 50 *F – 10 *C
4450 ohms = 59 *F – 15 *C
3520 ohms = 68 *F – 20 *C
2796 ohms = 77 *F – 25 *C
2238 ohms = 86 *F – 30 *C
1802 ohms = 95 *F – 35 *C
1459 ohms = 104 *F – 40 *C
1188 ohms = 113 *F – 45 *C
973 ohms = 122 *F – 50 *C
667 ohms = 140 *F – 60 *C
467 ohms = 158 *F – 70 *C
332 ohms = 176 *F – 80 *C
241 ohms = 194 *F – 90 *C
177 ohms = 212 *F – 100 *C
132 ohms = 230 *F – 110 *C
100 ohms = 248 *F – 120 *C
77 ohms = 266 *F – 130 *C
60 ohms = 284 *F – 140 *C
47 ohms = 302 *F – 150 *C

 

Walbro fuel pump flow rates and current draw at 12V

Pressure (psi)	190 ltr/hr pump (gal/hr)	190 ltr/hr pump (amps)	“high pressure” 190 ltr/hr pump (gal/hr)	“high pressure” 190 ltr/hr pump (amps)	255 ltr/hr pump (gal/hr)	255 ltr/hr pump (amps)	“high pressure” 255 ltr/hr pump (gal/hr)	“high pressure” 255 ltr/hr pump (amps)
0	56	2.6	53	2.8	75	4.7	76	4.4
10	52	3.2	50	3.5	72	5.2	73	4.8
20	48	4.0	48	4.3	67	6.1	68	5.5
30	44	4.8	44	5.0	62	7.2	63	6.3
40	40	5.7	41	5.9	58	8.2	59	7.1
50	36	6.6	38	6.8	53	9.3	54	8.0
60	32	7.6	35	7.8	49	10.6	51	8.9
70	28	8.6	31	8.8	40	11.8	46	9.9
80	22	9.7	29	9.9	29	13.3	41	11.0
90	12	10.8	25	10.9	0	14.6	32	12.0
100	0	12.5	21	12.0			22	13.2
110			17	13.5			11	14.5
120			11	15.0			1	15.8

Walbro fuel pump flow rates and current draw at 13.5V

Pressure (psi)	190 ltr/hr pump (gal/hr)	190 ltr/hr pump (amps)	“high pressure” 190 ltr/hr pump (gal/hr)	“high pressure” 190 ltr/hr pump (amps)	255 ltr/hr pump (gal/hr)	255 ltr/hr pump (amps)	“high pressure” 255 ltr/hr pump (gal/hr)	“high pressure” 255 ltr/hr pump (amps)
0	63	3.1	60	3.3	82	5.2	85	5.0
10	61	3.5	58	3.9	81	5.9	82	5.2
20	57	4.2	56	4.5	76	6.5	79	6.0
30	52	5.0	52	5.3	71	7.8	73	6.8
40	49	5.8	50	6.2	68	8.6	70	7.5
50	46	6.6	47	7.2	62	9.8	65	8.2
60	42	7.5	45	8.0	58	10.8	61	9.1
70	38	8.4	41	8.8	50	12.0	56	10.2
80	32	9.4	38	9.8	39	13.3	51	11.1
90	22	10.3	34	10.9	11	14.4	43	12.1
100	14	11.5	31	12.0	1	15.0	32	13.2
110		12.7	28	13.2			20	14.3
120			22	14.5			11	15.7
130			18	16.0				17.0

There are three basic models of Walbro pumps and for each there are three sub-models that only have different fuel line connections. The GSS242, GSS250, and GSS278 flow 190 lph. The GSS307, GSS315, and GSS317 flow 255 lph. The GSS340, GSS341, and GSS342 flow 255 lph and are made for high pressure configurations.