I just want to replace the car's original brakes with stock replacements. Guess there was a standard and performance brake option from the factory. How do I know which my 87 Iroc has?

My RPO codes...

AC3: ADJUSTER, FRT ST, POWER, 6 WAY, BKT, DRIVER
AG9: ADJUSTER, SEAT, POWER, 6 WAY
AM9: SEAT, RR, SPLIT, BACK, FLDG
AR9: SEAT, FRT BKT, EUROPEAN STYLE, PASS A DRIVER RECL
AU3: LOCK CONTROL, SIDE DR, ELEC
A01: WINDOW, TINTED, ALL SHADED, W/S
A31: WINDOW, POWER OPERATED, SIDE
A90: LOCK CONTROL, RR COMPT LID, REM CONT ELEC RELEASE
B18: ORNAMENTATION, INTR, DELUX
B2L: PERFORMANCE PACKAGE & ENGINE PACKAGE V8 5.7LPFI
B34: COVERING, FRT FLOOR MATS CARPETED INSERT
B35: COVERING, REAR, FLOOR MATS CARPETED INSERT
B4Z: IROC PACKAGE
B84: ORNAMENTATION, EXTR MLDG, B0DY SIDE
B91: ORNAMENTATION, EXTR MLDG DR EDGE GUARD, COLORED
B94: FENDER EMBLEM, Z28
B97: ORNAMENTATION, EXTR MLDG, LOWER ACCENT
CD4: WIPER SYSTEM WINDSHIELD, PULSE
C49: DEFOGGER, RR WINDOW, ELECTRIC
C60: HVAC SYSTEM, AIR CONDITIONER FRT MAN CONTROLS
DD8: MIRROR I/S, R/V, LT SENSITIVE
DG7: MIRROR 0/S, LH & RH, REM CONT, ELEC, PAINTED
DK6: CONSOLE ROOF, INTERIOR
D08: PAINT, HIGH GLOSS FINISH
D34: MIRROR, VISOR VANITY
D42: SHADE, RR COMPT SECURITY
D6M: GEAR, SPEEDO DRIVEN
D80: SPOILER, RR END PNL
D88: DECAL, STRIPE, SPORT
E5Z: SPEEDOMETER ADAPTER (DELETE)
E7Z : SENSOR, VEHICLE SPEED (DELETE)
E9Z: SPEEDOMETER KEY (DELETE)
FE2: SUSPENSION SYSTEM, RIDE HANDLING
GW6: AXLE REAR, 3.27 RATIO
G80: AXLE POSITRACTION, LIMITED SLIP
J65: BRAKE SYSTEM, PWR, FRT & RR DISC
KC4: COOLING SYSTEM, ENG OIL
K34: CRUISE CONTROL, AUT0MATIC, ELECTRONIC
K68: GENERATOR,105 AMP
L98: 5.7 LITER V8 TPI ENGINE
MD8: TRANSMISSION, AUTO 4 SPD, THM 700 R4
MXO: MERCHANDISED, TRANS, AUTO PROVISIONS, O/D
NA5: EMISSION SYSTEM, FEDERAL, TIER O
NOD : ASSEMBLY PLANT, NORWOOD, OHIO
NP5: LEATHER WRAPPED, STEERING WHEEL AND SHIFT ****
N33: STEERING COLUMN, TILT TYPE
N65: WHEEL & TIRE,SPARE, SPACE SAVER, STEEL
N96: WHEEL, 16 X 8, CAST ALUMINUM
PB4: LOCK CONTROL, WHEEL
P20: HUBCAPS, WHEEL, STYLED
QDZ: TIRE ALL, P245/50VR16/N BL R/PE ST TL HW4
TR9: LAMP, GROUP
TT4: HEADLAMPS, HALOGEN, 4
T93: TAIL & STOP LAMP, SMOKED
T96: LAMP, FOG
UQ1: RADIO PROVISIONS, FOR STEREO
UX1: RADIO, AM/FM STEREO CASSETTE EQUALIZER
U21: CLUSTER, INST, OIL, COOL TEMP, VOLTS, TACH
U25: LAMP, INTR, RR COMPT, COURTESY
U26: LAMP, INTR, ENG COMPT, COURTESY
U29: LAMP, INTR I/P, COURTESY
U79: SPEAKER SYSTEM, 4, DUAL FRT COAX, DUAL EXT RGE PKG
V73: ANTENNA, FIXED
YR1: SEAT,FRT CUSTOM
YS1: SEAT,RR CUST
YT1: BUILD UP DR & QTR
YT9: OPTION PACKAGE, FISHER FURNISHED PARTS
Z28: MERCHANDISED PKG, SPECIAL PERFORMANCE
1AY: STOCK ORDERS PROCESSING OPTION (DEALER ORDERED CAR)
1HV: COMPONENTS OF IROC PACKAGE
1SC: PACKAGE, OPTION 03
6ZX: SPRING, COMPUTER SELECTED, FRONT, LEFT HAND
7ZX: SPRING, COMPUTER SELECTED, FRONT, RIGHT HAND
72C: TRIM COMBINATION, CLOTH, DK CARMINE (C)
72I: INTERIOR TRIM, DK CARMINE (91)
729: SEAT BELT COLOR, DK CARMINE (9) (91)
74Q: MOLDING COLOR, FLAME RED MET (91)
74U: PRIMARY COLOR, EXTERIOR, VICTORY RED (91)
8NL: SPRING, COMPUTER SELECTED, REAR, RIGHT HAND
88A: STRIPE COLOR, ACCENT, TWO TONE, GOLD/BLACK (91)
9NL: COMPUTER SELECTED REAR RIGHTHAND SPRING
92P: WHEEL COLOR GOLD

 

You have the standard 10.5" brakes.

 

Thank you. I was searching but wasn't sure what rpo designated the upgraded brakes in 87. Would that be in the G92 package, or?

 

The upgraded front brakes would be included in the RPO code 1LE. An extremely rare option.