This spid was posted in another thread and it looks like an IROC with 16 inch wheels (QDZ) and hub caps (P20). Was this possible?

 

In this case P20 probably isn't related to hubcaps.. at least not full wheel cover style hubcaps. From the other info on the SPID we know it's a 1987 Iroc, black, with black interior. I'd surmise that the P20 code probably indicates something relating to the wheels based on the P in the code. It might indicate the color of the IrocZ logo on the centercap. I'll research it a bit more and post back if I find anything.

 

My 87 has the same P20 code. Maybe it refers to the iroc badge on the center caps? no idea.....

AC3: ADJUSTER, FRT ST, POWER, 6 WAY, BKT, DRIVER
AG9: ADJUSTER, SEAT, POWER, 6 WAY
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
B3W: ADVANCE PRICE SHEET
B34: COVERING, FRT FLOOR MATS CARPETED INSERT
B35: COVERING, REAR, FLOOR MATS CARPETED INSERT
B4Z: IROC PACKAGE
B84: ORNAMENTATION, EXTR MLDG, BODY SIDE
B94: FENDER EMBLEM, Z28
B97: ORNAMENTATION, EXTR MLDG, LOWER ACCENT
CD4: WIPER SYSTEM WINDSHIELD, PULSE
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)
E72: BODY LENGTH, INCR I8 INCH
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
VK3: LICENSE PLATE, FRT MOUNTING 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
1A2: SEO VEHICLE, PUBLIC SERVICE
1HV: COMPONENTS OF IROC-Z PERFORMANCE PKG(CHEV)
1SC: PACKAGE, OPTION 03
15P: WHEEL COLOR SILVER METALLIC (91)
6ZX: SPRING, COMPUTER SELECTED, FRONT, LEFT HAND
7ZX: SPRING, COMPUTER SELECTED, FRONT, RIGHT HAND
8NL: SPRING, COMPUTER SELECTED, REAR, RIGHT HAND
81Q: MOLDING COLOR, BRIGHT RED (91)
81U: PRIMARY COLOR, EXTERIOR, BRIGHT RED (91)
82C: TRIM COMBINATION, CLOTH, MED DK GRAY (C) (91)
82I: INTERIOR TRIM, MED DK GRAY (91)
829: SEAT BELT COLOR, MED DK GRAY (91)
86A: STRIPE COLOR, ACCENT, TWO TONE RED/GUNMETAL (91)
9NL: COMPUTER SELECTED REAR RIGHTHAND SPRING

 

No P20 RPO found in my 85 IROC.

JamesC

 

Just from looking around, P20 shows up on more then a few rpo lists from 87 Irocs including my own. There's also a couple older posts with the code showing up on a non-Iroc Z28, and some 6 cylinder cars. I can't find any definition for the code other then styled hubcaps, but that doesnt necessarily mean it has anything to do with hubcaps or even wheels in this case. Some RPOs were used on different platforms and had similar definitions but the actual parts were different. For example, N90 can mean 15x7" five spoke Z28 style wheels, but it also means 15x7" diamond spoke aluminum wheels on the Firebird. These dual definitions existed in the same year.

Keeping in mind that the purpose of the SPID is for Service Parts Identification, the best place to find what P20 really refers to would probably be the parts catalog. It may very well mean different things in different years on different platforms, but the catalog may show what part depends on code P20.

 

I checked my buildsheet and it has P20 STYLE HUB CAP right on the list. I would think that this references the center cap in one way or another. JamesC should also have this if it does refer to the center cap since the 85 and 87 is the same wheel. I can't really speculate what else it could mean. Maybe Drew is right and it has to do with the color of the center cap. JamesC, the center caps are red on your car instead of silver, right?

 

I've got P20 in my codes also and been trying to decode all mine
since hopefully the build sheet is still under the carpet somewhere

As a footnote,

Thats my RPO sheet in MR396 post!
And the wheels are gold and has black cap with gold Iroc letters.
And since Scott's rims aren't gold has to be another option.

Curious?

Later

 

The IROC rims had been removed when I purchased the car, so I have no idea what they might have originally been. However, I was told a while back that red graphics got red IROC caps (and that's what I'm currently running). I double-checked the RPO's and there is no P20 listed.

For what the info is worth, the following from Subroc:

Gold wheels/gold door decals = gold center caps
Silver wheels/red decals = red center caps
Silver wheels/silver decals = silver center caps

JamesC

 

I found an Iroc with the P20 code and Gold accents. My Iroc has Silver accents. So it's not the color of the cap...

 

I dug out a GM Production Options booklet (Service Parts Operations/General Motors Corporation/Engineering Department) for the following:

RPO = P20
RPO Name = Hubcaps
Divisional RPO Description = Wheel, Styled

How's that for muddying the water.

I had a moment to check my 82-91 Chevy Parts & Illustration Catalog this morning. I found some interesting facts--N90 would the 15" version:

Cap, Hub "IROC Z" (1988 W/N90, Z28) (Silver) [etc.]

Another:

INSERT, Hub Cap (1987, W/N90, P20)

An interesting side bar is that while the IROC N96, 85 and 86, is shown in the above CD, no hub caps/center caps are shown with them as in other years.

1987 is the only year that shows P20.

JamesC