NCRS Lingo Defined

This page is a work in progress.  It is here to help establish a dictionary of NCRS Lingo.  New members and old members alike sometimes question what some of the terms used to describe our Corvettes and the restoration process that we go through to make them ready for NCRS Flight Awards.   Terms with an * are taken from an official GM Abbreviations/Acronyms Manual.

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

 A

A/C
Air conditioner/air conditioning. *

AAP
Auxiliary accelerator pump *

ABC
Assembly broadcast code *

ABL
Assembly breakdown list *

ABS
Adaptive brake system  /  anti-lock braking system (called ALB by Honda) *

AC
AC Spark Plug Division (of GM, formerly, now AC Rochester) *

AC/R
AC Rochester, Flint MI *

ADC
Advanced Development Center (of C-P-C), Pontiac MI *

AFB
Aluminum 4-bbl carburetor *

AIC
Air intake control *

AIM
Assembly Instruction Manual

AIR
Air Injection Reactor system. * Part of the early smog equipment.

Air Box
Special aircleaner ducted to a hole in the radiator support to provide cool air to the Fuel Injection on 43 race prepared 1957 Corvettes.

ALL
Automatic load leveling ( suspension) *

ALS
All season tire *

alt
Alternator *

AMA
Automobile Manufacturers' Association

APD
Assembly process deviation *

ARC
Automatic ride control (suspension) *

AS
Active suspension system *

ASR
Anti-slip regulator system *

ASSEM
Assembly *

ATDC
After top dead center *

ATS
Air temperature sensor *

B              top

BBC
Big Block Chevrolet engine. Engines that started in 1965 with 396 cubic inches and progressed to 427 cubic inches for 1966 and then to 454 cubic inches from 1970 - 1974.

BC/CC
Base coat/clear coat paint *

BHP
Brake horsepower *
Big Block
Engines that started in 1965 with 396 cubic inches and progressed to 427 cubic inches for 1966 and then to 454 cubic inches from 1970 - 1974.

Big Brake
Big Brake option available on 1957 through 1962.

Big Tank / Tanker / No Carpet Club
Optional larger gas tank, available 1959 through 1967.
Bolt on Wheels
Aluminum wheels on 1967 Corvette that appeared very much like the 1963-66 Knock-off wheels, except that they bolted on just like standard wheels.

BOM
Bill of materials, used at prototype build sites as part number list for each vehicle *

Broach Marks
The marks on the deck of the block including the stamp pad, created by the factory machining operation. Broach tool; leaves lines as the cutter moves across the deck in a straight line from front to back. The ridges or grain of the marks will vary quite a bit from engine to engine as the tooling wears or other factors enter into the process.   Re-stamped blocks are first decked to erase the original numbers and; most automotive machine shops cut and leave broach marks across; the block side to side, which are readily detected when inspecting a stamp pad.  However, some very cleaver and expensive shops cut the blocks like the factory so they can re-stamp and be nearly undetected.

BPEGR
Back pressure exhaust gas recirculation *

BSW
Black sidewall tire *

BTC
Body Technology Center *

BTDC
Before top dead center *
Build sheet, Tank Sticker
It lists all the options the car had originally. Starting in with '67s, it is glued to the top of the gas tank. Later years also may find them stashed various places inside the car. A great piece of authentication, since Chevy has no records of how each car was equipped. The National Corvette Museum has recently been given access to copies of all of the build sheets from the Bowling Green Plant.  This applies to 1981 and later cars that were manufactured at Bowling Green.  The Museum is now offering a service of reproducing a copy of the build sheet and the Window Sticker.  See the NCM web site for further information.  Like everything else, can be faked.

BWO
Build work order *

C              top


C1
1953 -1962 Corvettes.  The solid axle or straight axle cars.

C2
1963 - 1967 Corvettes. Mid-years and Sting Ray years.

C3
1968 - 1982 Corvettes. Includes 1968 Shark, and 1969 - 1976 Stingray years.

C4
1983 - 1996  *note: There were no 1983 production cars due to plant change over from St. Louis to Bowling Green.

C5
1997 - 2004 Corvettes.

C6
2005 - and later Corvettes.

CAFE
Corporate average fuel economy *

CAMSHF or CAM
Camshaft *

Casting Number
Part number cast into a part as it is produced.  Many castings also have a date code cast into the part as well.  Parts such as blocks, manifolds, heads, transmission cases, differential cases and many more have casting numbers that identify them as particular to certain applications.  On most Chevrolet blocks the casting number is located on the bellhousing flange behind the driver's side head.  This can usually be seen even with ignition shielding in place.

CB
Citizens band (radio) *

CDI
Capacitor-discharge ignition system *

CEL
Check engine light (display) *

CFI
Cross fire injection *

CID
Cubic inch displacement (of engine) *

COM
Chassis Overhaul Manual

Convertible
Cars with a fold down canvas like top, and roll up windows.

COPO
(Chevrolet) Central Office Production Options (formerly), now SEO * Combinations of options that were generally not available to the public. The order was generated through the Chevrolet Central Office.

Coupe CPE *
A closed car with two doors.

CPO
Chevrolet part number only *

Crossfire Injection
Standard on 1982 & 1984 model's only.  First fuel injection since 1965 two injectors in a throttle body setup.
 
CSM
 
Chassis Service Manual
 
CVJ
Constant velocity joint *

D          top

Date Code
Almost every mechanical part made for a Corvette has a date code either cast or stamped into it. These are used by the manufacturer to track quality control.  They are now used to determine if the part is probably correct for the Corvette it is installed on.   An engine with a date code of C 10 4 (March 10, 1964) could not be correct for a '63 Corvette as the engine was made after the car was made. Parts too early are usually not correct either, as they would have been installed on an earlier vehicle, such as a D 19 5 (April. 19, 1965) in a '67 Corvette. The date code on an engine block is typically on the bellhousing flange behind the distributor. On early big blocks, it was on the passenger side near the pan rail, but later (1970) moved up to the same location as the Small Blocks.

DIST
Distributor (an engine part) *  Distributes spark from coil to spark plugs.   Controls spark timing.

DLI
Distributorless ignition system *

Documentation,  History
Depends on who is listening to the pitch. Many cars have no documentation or history. It is a good thing to have. You can check up on when modifications were done, where stuff like missing ignition shielding went, etc. If there is something atypical about the car, like a hand-stamped block, you can sometimes get affidavits from former owners that this is the original block and was never removed from the car.

DWO
Design work order

DYNO
Dynamometer *  Device for measuring mechanical force, or power.

E

EAM
Engine assembly manual *

EC
Engineering change *

ECS
Electronic Controlled Spark

EEC
Evaporative Emission Controls

EFI
Electronic Fuel Injection

EGR
Exhaust gas recirculation *

EIN
Engine identification number *

F

FI - Fuelie
Fuel Injection.  Early cars 1957 - 1965 used Fuel Injection that was unlike our modern electronic Fuel Injection cars of today.  They often were very difficult for mechanics to adjust or maintain.  They were often taken off of cars and replaced with carburetors.  That history leads to today's restored Fuel Injection cars being a little rare.

G        top

GMSPO
General Motors Service Parts Operations *

H

H/prf - HI-PERF - HP
High performance *

HEI
High energy ignition system *

hp
Horsepower *  One hp equivalent of 550 ft. lbs. per second

I

J

Judge
NCRS Judges are volunteer members who offer their time and knowledge to Judge Members Cars under the guidance of the NCRS Technical Information Manual & Judging Guide. Master Judge (see Master Judge).

K

K-H
Kelsey-Hayes Co., Romulus, MI

King of the Hill
See ZR-1

Knock Off / KO / Knock Off Aluminum Wheel Option
Optional wheel available during 1963? or 1964 through 1966 Model years.

L

L - series engines were designated by their RPO Numbers.  See RPO.

1963 -
L75: 300 hp w/AFB - L76: 340 hp w/AFB and Hi-Lift Cam - L84: 360 hp w/FI and Hi-Lift Cam

1964
L75: 300 hp w/AFB - L76: 365 hp w/Holley and Hi-Lift Cam - L84: 375 hp w/FI and Hi-Lift Cam

1965
L75: 300 hp / 327 - L76: 365 hp / 327 and Hi-Lift Cam - L78: 425 hp / 396
L79: 350 hp / 327 with AFB and hyd/Hi-Lift Cam - L84: 375 hp w/FI and Hi-Lift Cam

1966
L36: 390 hp / 427 - L72: 425 hp / 427 - L79: 350 hp / 327

1967
L36: 390 hp / 427 - L68: 400 hp / 427 - L71: 435 hp / 427 - L79: 350 hp / 327
L88: 430 hp / 427 - L89: 435 hp w/ Aluminum Heads

1968
L36: 390 hp / 427 - L68: 400 hp / 427 - L71: 435 hp / 427 - L79: 350 hp / 327
L88: 430 hp / 427 - L89: 435 hp w/ Aluminum Heads

1969
L36: 390 hp / 427 - L46: 350 hp / 350 - L68: 400 hp / 427 - L71: 435 hp / 427
L88: 430 hp / 427 - L89: 435 hp w/ Aluminum Heads

1970
L46: 350 hp / 350 - LS5: 390 hp / 454 - LT1: 370 hp / 350

1971
LS5: 390 hp / 454 - LS6: 425 hp / 454 - LT1: 330 hp / 350

1972
LS5: 270 hp / 454 - LT1: 255 hp / 350

1973
LS4: 275 hp / 454 - L82: 250 hp / 350

1974
LS4: 270 hp / 454 - L82: 250 hp / 350

1975
L48: 165 hp /350 - L82: 205 hp / 350

1976
L48: 180 hp / 350 - L82: 210 hp / 350

1977
L48: 185 hp / 350 - L82: 210 hp / 350

1978
L48: 185 hp / 350 - L82: 220 hp / 350

1979
L48: 195 hp / 350 - L82: 225 hp / 350

1980
L48: 190 hp / 350 LG4:180 hp / 305 (California Legal) - L82: 230 hp / 350

1981
L81: 190 hp / 350   Legal for 50 States.  No optional engines offered.

1982
L83: 200 hp / 350   Legal for 50 States.  No optional engines offered.

Long Block
Replacement engine assembly includes block, crank, cam, pistons, rods, heads and valve train components all assembled and ready to install.  Timing gears and chain are also included.  The oil pump is commonly installed.  This is the basic engine including all of the parts for that base engine.  Things like covers, waterpumps, flywheels, and other parts that may vary depending on the application are not included.   This engine may be serviceable in a Corvette or a 9 passenger van.  Either with an automatic transmission or four speed.  Fuel delivery may be carburetor, or fuel injection.  This is why certain parts may be included on one version and deleted on another.  GM refers to this as a "Targetmaster" engine.

M

Master Judge
NCRS Master Judges are volunteer memberswho have been recognized by the organization and membership for accumulating a minimum of 100 points in our judging recognition program by Judging at events, attending Judging Schools at Chapter Meets, Regional Meets and National Meets. Many have also attended National or Regional Judging Seminars that last for one or two days of intensive instruction and hands on participation.

NCRS 200 Club:
An individual who has been recognized by the organization and membership for accumulating a minimum of 200 points in our judging recognition program.

NCRS 300 Club:
An individual who has been recognized by the organization and membership for accumulating a minimum of 300 points in our judging recognition program.

NCRS 400 Club:
An individual who has been recognized by the organization and membership for accumulating a minimum of 400 points in our judging recognition program.

NCRS Red Hat Master Judge:
An individual who has been recognized by the organization and membership for accumulating a minimum of 100 points in our judging recognition program, and participating as an owner in the judging program achieving one of our highest awards offered, either the NCRS Duntov Mark of Excellence, the NCRS McLellan Mark of Excellence, the NCRS Hill Mark of Excellence, or the NCRS-Chevrolet Bowtie Preservation Award.

NCRS Master Tabulator:
An individual who has been recognized by the organization and membership for accumulating a minimum of 100 points in our tabulation recognition program.


Midyear
1963 - 1967 Corvettes. Mid-years and Sting Ray years.

Mouse Motor
Chevrolet small block 265,283,302,327,350 are often referred to by the term "Mouse Motor".

MSRP
Manufacturers suggested retail price including dealer preparation *

N


NCM
National Corvette Museum.  Bowling Green, KY.  Just across the road from the Bowling Green Corvette Plant. NCM web site

NM
*NM* NCRS Technical Discussion Board and NCRS Discussion Board.   Identifies a message with no content, or no message.
 
NOM
Not Original Motor. This may or may not matter to you, but it probably will to someone else if you have to sell the car later. Pay less for NOM.

NORS
NORS refers to New Old Replacement Stock.  These are parts that have been laying around in their original boxes since who knows when.  They are usually preferred over reproduction parts, but they are not always correct for your car.  There were many parts for our Corvettes that were used on the assembly line that were never sold as replacement parts.   For any number of reasons the replacement parts could be configured differently than the parts that the car was delivered with.  That is one of the reasons that NCRS is so serious about Bowtie cars.  These are examples of cars that remain unrestored, unmolested original cars.  They may not look like much to the casual observer, but to many NCRS members they are a living laboratory where we can see how the factory assembled these cars and what parts were used on the days that our example car was assembled.

NOS
NOS refers to New Old Stock.  These are parts that have been laying around in their original boxes since who knows when.  They differ from NORS in that the part is identical to the part used during assembly. The problem here is knowing NOS from NORS. Experience and consulting with Team Leaders, Master Judges, and other trusted sources is the only way to know.

MPL
Master parts list (computer code) *

MVMA
Motor Vehicle Manufacturers' Association (successor to AMA)

O          top

OEM
Original Equipment Manufacture.  Many times these are not manufactured by GM but subcontracted to one or more vendors.  The parts from different vendors may vary slightly.  These parts often were and are mixed during the production runs.

P

Partial Engine
See Short Block.

PBM
Prototype build manual *

PCV
Positive crankcase ventilation *

Performance Parts Engine Assembly "GM"
A high performance SERVICE engine assembly usually configured differently than any available PRODUCTION engines. It is composed of PRODUCTION and GMPP components

PG
Powerglide Transmission

PID
Part identification (in MPL) *

P/N  PTN
Part number

Positrac / Positraction / Posi
Limited slip differential.

Production Engine Assembly
A full-dressed PRODUCTION engine, just as delivered to the vehicle assembly plants, which is sold through SERVICE. These are exactly the same as the engine installed in passenger cars or trucks. PRODUCTION engine assemblies are usually only available during the current model year or until GMSPO inventory of the PRODUCTION engines is exhausted.

Protect-o-plate
This a metal warranty card which has the original purchaser's name on it. It also has some information on the original configuration of the car, not as extensive as the build sheet.  It was first included in 1965.

Q

R

Rat Motor
Chevrolet big blocks of any year 348ci, 366ci, 396ci, 402ci, 409ci, 427ci, 454ci were referred to as "Rat Motors".

Roadster
1953 -1955 Corvettes were roadsters, they had side curtains, no roll up windows.   NCRS does consider Convertible the same as Roadster.

RPO / Regular Production Option  *
Optional equipment from engines to vanity mirrors that were generally available to the public.

S          top

SBC
Small Block Chevrolet engine. Chevrolet engines derived from the 265 cubic inch, block design first introduced in 1955.  SBC's include 283's, 302's, 305's, 307's 327's, 350's, and 400's.

Service Engine
This is an engine assembly which is composed of all PRODUCTION pieces and is configured the same as a PRODUCTION configuration. It usually lacks some of the peripheral components which must be transferred from the replaced engine or otherwise acquired. When completed, it will have the same configuration as the replaced engine.

Shark
1968 Corvettes were designated Shark.

Side Pipe / Side Exhaust
Optional equipment available on 1965 through 1967 and 1969.

 
Short Block
Replacement engine that usually includes only the block, crank, connecting rods, pistons, camshaft, timing gears and chain.  It is all assembled and ready for heads and valve train components, intake manifold, carburetor or fuel injection, exhaust manifolds, and other items too numerous to mention.  This referred to as a "Partial Engine" by GM

SHP / Special High Performance
A Higher performance carburetor engine, either small block or big block, generally with a mechanical lifter cam, however, some had special hydraulic lifter cams.

Small Block
Chevrolet engines derived from the 265 cubic inch, block design first introduced in 1955.  SBC's include 283's, 302's, 305's, 307's 327's, 350's, and 400's.

 
Sting Ray
1963 - 1967 Corvettes were designated Sting Ray. Note there seems to be some question of the 1968 model was it a Sting Ray, or a Stingray, or neither?

Stingray
1969 - 1976 Corvettes were designated Stingray.

Straight Axle / Solid Axle
1953 -1962 Corvettes.  These are the Corvettes that predate the 4 wheel independent suspension of 1963 and later cars.

SWC - S/W/C * Split Window Coupe
1963, only Corvette Coupe with the two piece rear window.  One year only feature due to poor rear visibility.

T          top

T-3
Guide Lamp T-3 headlamps used from 1956 to 1972 in different configurations.

T-top
Removable top panels.  Two panels one over the drive seat and the other over the passenger seat.

Tank Sticker, Build Sheet
It lists all the options the car had originally. Starting in with '67s, it is glued to the top of the gas tank. Later years also may find them stashed various places inside the car. A great piece of authentication, since Chevy has no records of how each car was equipped. The National Corvette Museum has recently been given access to copies of all of the build sheets from the Bowling Green Plant.  This applies to 1981 and later cars that were manufactured at Bowling Green.  The Museum is now offering a service of reproducing a copy of the build sheet and the Window Sticker.  See the NCM web site for further information.  Like everything else, can be faked.

Targa Top
Removable single top panel.  Opens car roof from side to side.

Target Engine
See Long Block.

TBI
Throttle body injection *

TCS
Transmission Controlled Spark.  Common in late 60's early 70's.

THM
Turbo Hydra Matic Transmission

TL
*TL* NCRS Technical Discussion Board and NCRS Discussion Board.   Used to denote posts by NCRS Team Leaders or other NCRS Officials.  It is used to identify posts as being genuine.

TI / Transistor Ignition

Tri Power / 3 deuces / 3 X 2 / Three two Barrel Carburetors

TRW
Thompson-Ramo-Wooldridge ( a GM supplier ) *

TCS
Transmission Controlled Spark

TWO
Test work order
 

U

V        top

VAC
 
Vacuum Advance Control

VIN
Vehicle Identification Number *

V Shield
Ignition shielding on lower sides of engine block.

W

X

Y

Z

Z06
The "ZO6" was the hottest '63 Corvette variation. Equipped with heavy-duty suspension and heavy duty brakes, it was only available as a 327 cubic inch 360 horsepower, fuel-injected 4 speed transmission Coupe. Early production provided a special 36 gallon fuel tank, later versions could be ordered with a standard fuel tank. 199 ZO6's were built, and less than 90 are believed to have been the "big tank" version.

ZR1
1970-72 Special Purpose Package: (Not recommended for normal traffic situations)   Includes LT1, 370-hp 350 cu-in. engine, special 4-speed close-ratio transmission, HD power brakes, full transistor ignition system, aluminum radiator, special springs with matching shock absorbers, special front and rear stabilizer bars.  1972 included 255-hp engine available for registration in California.

ZR-1
1990-95 LT5 engine, an aluminum-block V-8 with the same bore as the standard (L98) 350ci displacement unit, but with 375 horsepower. To accomplish this power boost, the new block featured four overhead camshafts and 32 valves. The LT5s were built by Mercury Marine in Oklahoma and assembled into the ZR-1 vehicle at Bowling Green.  Available only in coupe configuration, the ZR-1 was distinguishable from other Corvette coupes by its wider tail section, its now convex rear fascia and four "square" taillights. 6,939   ZR-1s were turned out.

ZR2
1971-72 Special Purpose Package: (Not recommended for normal traffic situations)   Includes LS6, 425-hp 454 cu-in. engine, special 4-speed close-ratio transmission, HD power brakes, full transistor ignition system, aluminum radiator, special springs with matching shock absorbers, special front and rear stabilizer bars.

 

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