98 Auburn, 99-02 Torsen M6 GU6 3.42 Standard A4 GU2 2.73 Standard A4 GU5 3.23 Optional (standard gear set with an SS/WS6/Firehawk) A4 G92 3.15 (Vette optional) 28 Spline Axle 10 bolt rear end
How to tell if you have an LS6 Block
15% of 01s and 25% of 02’s got the LS6 Block. The only way to tell 100% is to check the casting number. As you can see in the above pic (my ls6 block [Mr. Cool] ) the casting number is at the top of the deck on the drivers side. Take a mirror and place it behind the block and check or jack up the car and attempt to look from the bottom. The “easier†ways are the casting hue and bulleye methods but none are conclusive. If you really want to know if you have the block you’ll need to do the work and look for yourself, end of story.
Once you have determined if you have an LS6 block (ya you), then the only benefit to the block are the bay windows.
Its generally accepted from most engine builders that if your going for an extreme setup that the LS1 block offers more structural strength over the LS6 block.
OEM Cam Specs
OEM HP Ratings
General Motor Information
Vin Decoding
below is an example of a vin from a 2001 car: 2G1FP22G912108833
1st Country 2 Canada
2nd Manufacturer G General Motors
3rd Make 1 Chevrolet
4th Carline Code F F-Body
5th Series P Camaro (All Models)
6th Body Type 2 2-Door Hatchback Coupe
7th Restraint Syst. 2 Manual seatbelts (Driver & Passenger Inflatable)
8th Engine G LS1 5.7-Liter V8 346-cid Engine
9th Check Digit 9 Your VIN’s Check Digit: 9 Computed Check Digit: 9
10th Year 1 2001
11th Factory 2 Ste. Therese, Quebec, Canada
12th – 17th Seq. Prod # 108833 108833
Trannies
- Torque Convertors: How they Work– What size is right for you? depends on the application DO YOUR OWN RESEARCH, start in the Automatic Transmission Forum we have here, its there for a reason . General rule is 3200-3600 for daily drive, 4k+ for alot of track use.
- Manual Transmissions: How they Work– When looking to upgrade think of current and future mods. 01-02 cars come with the ls6 clutch and hydraulics which is a good setup for basic bolt on and daily driving.
– You’ll find the Spec 3 to be one of the most popular clutch setups here. Ram also makes a nice setup. Again, Do your OWN research n he Manua Transmission forum concerning chatter, clutch break in, hydraulics, ect. 98-00 cars will want to upgrade to the 01+ hydraulics when installing a new clutch.
RPO Code List
AG1 – Power Adjuster, Driver Front Seat, Multi-Directional
AK5 – Inflatable Restraint System, Driver and Passenger Seat
AQ9 – Front Bucket Seat, Driver and Passenger Recline
AR9 – Front Bucket Seat, Driver and Passenger Recline, European Style
AU0 – Remote Entry Lock Control
AU3 – Side Door Electric Lock Control
AX4 – Restraint Conversion Seat, Manual European
A26 – Window Glazing, European
A31 – Window, Power Operated, All Doors
A90 – Lock Control, Right Component Lid, Remote Control Electronic Release
BAG – Parts Package Export
BBS – Knob Shifter Hurst
B35 – Covering Rear Floor Mats
B9W – Wiring Provisions, DRL Override
CC1 – Roof Hatch Removable Panels, Glass
C49 – Rear Window Defogger, Electric
C60 – HVAC System AC Manual Controls, Front
DD9 – Mirror, Breakaway, O/S LH & RH Remote Control Electric Color
DE4 – Sunshade, Removable Hatch Roof
DG7 – Mirror, O/S LH & RH Remote Control Electric Color
DL5 – Decal, Roadside Service Information
DS1 – Sales, Diplomatic
D21 – Sunshade, Windshield
D35 – Mirror, O/S LH Remote Control, RH Manual Control, Color
ETA – Harness, I/P Wiring #1
FE2 – Suspension System, Ride and Handling
FE4 – Suspension System, Special Ride and Handling
FE9 – Certification, Federal Emission
FLT – Fleet Processing Option
F41 – Suspension System, Front and Rear Firm Ride and Handling
GU2 – Axle Ratio 2.73, Rear
GU4 – Axle Ratio 3.08, Rear
GU5 – Axle Ratio 3.23, Rear
GU6 – Axle Ratio 3.42, Rear
G80 – Axle Positraction, Limited Slip
JAF – Brake Provisions, European
J65 – Brake System, Power, Front and Rear Disc
K05 – Heater, Engine Block
K29 – Module Powertrain Control
K34 – Cruise Control, Automatic, Electronic
K43 – Generator, 102 Amp
K68 – Generator, 105 Amp
LS1 – Engine, Gas V8 5.7L SFI Aluminum
L36 – Engine, Gas V6 3.8L MFI HO
MAE – Marketing Area Europe
MM5 – Merchandised Transmission, Manual 5 Speed
MM6 – Transmission, Manual 6 Speed O/D
MN6 – Merchandised Transmission, Manual 6 Speed
MX0 – Merchandised Transmission, Automatic O/D
M30 – Transmission, Auto 4 Speed Electronic
M49 – Transmission, Manual 5 Speed O/D
NA3 – Emission System, Japan
NC1 – Emission System, California
NF7 – Emission System, Federal
NK3 – Steering Wheel, Sport, Soft Rim, Simulated Leather
NM2 – Emission System Export, Leaded Fuel
NP5 – Steering Wheel, Leather Wrapped
NP7 – Steering Column, EEC Approved
NT3 – Emission System, EEC 00
NW9 – Traction Control, Electronic
N36 – Steering Wheel, 4 Spoke Sport
N60 – Wheel, Aluminum, Painted
N66 – Wheel, Styled Aluminum
N73 – Wheel, Custom Sport Var4 17″
N92 – Cover, Wheel, Bolt-on
N96 – Wheel, 16 X 8 Cast Aluminum
N98 – Wheel, 16 X 8 Cast Aluminum Chrome
PA6 – Wheel, Styled Painted
PW7 – Wheel, 16 X 8 Aluminum Styled
P05 – Wheel, Chrome
QB3 – Wheel, 16 X 7.5 Steel
QCB – Tire, All P235/55R16-96T BW AL2
QEA – Tire, All P215/60R16-94T BW AL2
QFK – Tire, All P275/40R17-93W BW HW4
QFZ – Tire, All P245/50R16 BWAL3
QF6 – Wheel 17 X 9, Aluminum
QII – Tire, All P215/60R16-94H BW AL3
QLC – Tire, All P245/50R16/N BL HW4
TR7 – Headlamps, Control Leveling System, Automatic
T2H – Ornamentation Exterior, Export Unique Requirements
T2J – Ornamentation Interior, Export Unique Requirements
T37 – Lamp, Fog, Deluxe
T39 – Lamp, Turn Signal, Auxiliary
T43 – Spoiler, Rear
T65 – Lamp System, Daytime Running, Export
T72 – Headlamps, LH, Rule of the Road
T78 – Headlamp Control, Delete
T79 – Lamp, Fog Rear
T82 – Headlamp Control, Automatic ON-OFF
T84 – Headlamps, RH Rule of the Road
T85 – Headlamps, LH Rule of the Road
T89 – Lamp, Tail & Stop, Export
T90 – Lamp, Signaling and Marker, Export
T96 – Lamp, Fog
UA6 – Theft Deterrent System
UB3 – Cluster, Instrument, Oil Cool Temp Volts Trip Odom Tach
UC2 – Speedometer, Instrument, Kilo & Miles, Positive Bias
UD4 – Alarm, Vehicle Speed, 120 K/H
UK1 – Frequencies, Japanese
UK2 – Lever, Directional Signal, Includes Multi-Functions
UK3 – Control, Steering Wheel, Accessory
UL0 – Radio, AM/FM Stereo Seek/Scan Auto Rev Music Search Cass Auto-Tone Clock ETR
UL2 – Frequencies, European
UL8 – Frequencies, Saudi Arabian
UM6 – Radio, AM/FM Stereo Seek/Scan Auto Rev Cass Clock ETR
UN0 – Radio, AM/FM Stereo Seek/Scan Compact Disc Auto Tone Clock ETR
UQ0 – Speaker System, 4 Dual Front Door Mounted, Dual STD RGE, Qtr/Shelf
UW3 – Radio, AM/FM Stereo Seek/Scan, Auto Rev Music Search Cass Data System Clock ETR
UZ7 – Speaker System 8, Quad Front Door Mounted, Dual Sail Panel, Dual Rear Hatch Amplifier
U12 – Speedometer, Dual Scale with Kilometer Odometer
U19 – Speedometer, Instrument, Kilo & Miles, Kilo Odometer
U59 – Speaker System 8, Dual Front Door Mounted, Quad Sail Panel, Amplifier
U73 – Antenna, Fixed Radio
U75 – Antenna, Power Radio
VA5 – Language Label, English
VD1 – Provision Options, Europe
VE1 – Provision Options, Japan
VE2 – Protector Source Applied
VG1 – Protector, Underhood Compound, Clear
VG4 – Protector, Undervehicle Compound, Black
VG9 – Protector Wax, Exterior Body
VH5 – Plate Vehicle Identification
VI6 – Fleet Incentive, American Standard
VJ1 – License Plate Rear Mounting Package, Japanese
VK3 – License Plate, Front Mounting Package
VL4 – License Plate, Front Mounting Package, EEC
VL5 – License Plate, Rear Mounting Package, Export
VL6 – License Plate, Front Mounting Package, Japanese
VP6 – Noise Control
VR6 – Hook, Tie-Down, Shipping
VR7 – Hook, Tow, Second, Rear
V12 – Cooling System, Power Steering Fluid
V76 – Hook, Tow
WS6 – Performance Package Special
WX7 – Wiring Provisions
W53 – Entertainment System Option C
W54 – Entertainment System Option D
W55 – Entertainment System Option E
W66 – Merchandised Package, Formula
W68 – Sales Package, Firebird Ground Effects
X10 – Entertainment System, Option L
X20 – Entertainment System, Option M
Y3F – Sales Package, Sport, Appearance Upfitter
Y4A – Exhaust Cat Back
Y4B – Provisions Level II Ultra Performance Suspension
Y4C – Lubricant Engine Oil & Performance
Y4D – Axle Torque Sensing Differential
Y4E – Cooling System Engine Oil
Y4F – Provisions Hurst Shifter
Y4G – Provisions Chrome Wheels
Y4H – Ornamentation Dash Plaque & Key Fobs
Y4J – Covering Floor Front Mats
Y4K – Protector Car Cover
Y4L – Provisions Spoiler
Y81 – Merchandised Package, Firebird
Y82 – Merchandised Package, Firebird, Trans Am
Y84 – Merchandised Package, Firebird Trans Am, GTA
Y87 – Merchandised Package, Performance Enhancement
1R3 – Vehicle Identification Label 1
1R4 – Vehicle Identification Label 2
LT1 Engine
Code Description
AG1 Adjuster, 6-Way Power, Driver Seat
AG4 Adjuster, 2-Way Manual, Driver Seat
AH3 Adjuster, 4-Way Manual, Driver Seat
AK5 Restraint System Front Seat, Inflatable, Driver and Passenger
AN4 Restraint Provisions, Child
AQ9 Seat, Passenger and Driver, Recline
AUO Lock Control, Remote Entry
AU3 Lock, Side Door, Electric
A31 Window, Power Operated, Side
A90 Lock, Rear Compartment Lid, Remote Control, Electric
B35 Floor Mats, Rear, Carpeted Insert
B84 Exterior Molding, Body Side
CC1 Roof Hatch, Removable Glass Panels
C41 HVAC System, Heater
C49 Defogger, Rear Window Electric
C60 HVAC System, Air Conditioner, Manual Control
DD9 Mirror, Outside, LH & RH, Remote Control, Electric, Breakaway, Painted
DE4 Sunshade, Removable Hatch Roof
DG7 Mirror, Outside LH & RH, Remote Control, Electric, Painted
DL5 Decal Roadside Service Information
D35 Mirror, Outside LH Remote, RH Manual, Painted
D82 Paint Special
FE2 Suspension system, Ride handling
FE9 Certification Emission, Federal
F41 Suspension System, Firm Ride Handling, Front and Rear
GU2 Axle, Rear 2.73 Ratio
GU4 Axle, Rear 3.08 Ratio
GU5 Axle, Rear 3.23 Ratio
GU6 Axle, Rear 3.42 Ratio
G80 Axle, Rear Posi-traction (Limited Slip)
ILD Trim, Interior Design
IL2 Trim, Interior Design
IPB Trim, Interior Design
IP2 Seat, Leather Sport Front Bucket, Driver & Passenger, Reclining
J41 Brake System, Power, Front Disc, Rear Drum, Cast Iron
J65 Brake System, Power, Front and Rear Disc
KG9 Generator, 140 Amp
K05 Heater, Engine Block
K34 Cruise Control, Automatic Electronic
K68 Generator, 1 05 Amp
LT1 Engine, 5.7L (V8) MFI
L36 Engine, 3.8L (V6) MFI
MM5 Transmission, 5-Speed Manual (Merchandising Option)
MM6 Transmission, Manual, 6-Speed, Borg Warner, 65mm, 2.66 1st, 0.50 6th, O/D
MN6 Transmission – 6-Speed Manual (merchandising Option)
MXO Transmission – Automatic O/D (Merchandising Option)
M30 Transmission – Automatic, 4-Speed, 4LE, Electronic
M49 Transmission, Manual, 5-Speed, Borg Warner, 77mm, 3.75 1st, 0.76 5th, O/D
NB6 Emission System, California Requirements, Tier 1
NC3 Tailpipe Modifications
NF2 Emission System- Federal Requirement, Tier 1
NK3 Steering Wheel, Sport, Soft Rim, Simulated Leather
NP5 Steering Wheel, Leather Wrapped
NW9 ASR Traction Control
N36 Steering Wheel, 4-Spokes, Sport
N60 Wheel, Aluminum, Painted
N92 Cover, Wheel, Bolt-On
N96 Wheel, 16×8, Cast Aluminum
N98 Wheel, Chrome, Var 2
P05 Wheel, Chrome, Var 1
P08 Cover, Wheel, Super Deluxe
QA7 Wheel, 16×7.5, Aluminum
QB3 Wheel, 16×7.5, Steel
QEA Tire, P215/6OR16 BW R/Pe ST TL AL2 94T
QFZ Tire, P24515OZR16 BW R/PE ST TL AL3
QII Tire, P21516OR16 BW R/PE ST TL AL3 94H
QLC Tire, P24515OZR161N BL R/PE ST TL HW4
STE Plant Code-St. Therese, PQ, GM of Canada
TR7 Headlamps, Automatic Control Leveling System
T39 Lamp Turn Signal, Auxiliary
T43 Spoiler, Rear
T61 Lighting- Daytime Running
T96 Lamp, Fog
UA6 Theft Deterrent System
UB3 Instrument Cluster, Oil, Coolant, Temperature, Volts, Trip Odometer, Tachometer
UK2 Lever, Directional Signal, Multifunction
UK3 Electronic System Accessory Control
UL0 AM/FM Cassette ETR 200 Watt Monsoon Sound System w/cassette
UN0 AM/FM Cassette ETR 200 Watt Monsoon Sound System w/CD player
UN6 Radio, AM/FM stereo, Seek/Scan, Auto Reverse Music Search Cassette, Clock, ETR
UQ0 Speaker System 4, Dual Front Door Mounted, Standard Range Quarter/Shelf
UU8 Radio, AM/FM Stereo, Seek/Scan, Auto Reverse Music Search Cassette, HPS, Clock, ETR
U1C Radio, AM/FM Stereo, Seek/scan, Compact Disc, Clock, ETR
U1S 12 Disc Compact Disc Changer
U1T Radio, AM/FM Stereo, Seek/Scan, Compact Disc, HPS, Clock, ETR
U18 Speedometer Instrument Kilometers
U19 Speedometer Instrument, Kilometers and Miles, Kilometer Odometer
U62 Speaker system 4, Dual Coax Front, Dual Coaxial Package shelf
U65 Speaker system 5, Dual Front Door Mtd, Dual Ext. Range Panel, Single Rear Compartment
U73 Antenna, Fixed
U75 Antenna, Power
VG8 Label, Vehicle, Notice to Buyer
VH5 Plate, Vehicle Information
VK3 License Plate, Front Mount Package
VP6 Noise Control
WS6 Performance Package – Formula/Trans Am
WU8 SS Performance Package/Appearance Package – Camaro
W51 Entertainment system – Radio, AM/FM-stereo, seek/scan, cassette, 4 Speaker system · Standard Range
W52 Entertainment System – Radio, AM/FM stereo, Cassette, Equalizer, 4 Speaker system – Coaxial
W53 Entertainment System – Radio, AM/FM Stereo, Compact Disc, Equalizer 4 Speaker System – Coaxial
W54 Entertainment System – Radio, AM/FM Stereo, Cassette, Equalizer, 10 Speaker System, Amplifier
W55 Entertainment System – Radio, AM/FM Stereo, Compact Disc, Equalizer 10 Speaker System, Amplifier
W57 Entertainment system – Radio, AM/FM stereo, Cassette, Equalizer, 4 Speaker system – Coaxial
W58 Entertainment system – Radio, AM/FM Stereo, Compact Disc, Equalizer, 4 Speaker system – Coaxial
W59 Entertainment system – Radio, AM/FM Stereo, Cassette, Equalizer, 6 Speaker System, Dual Front Door Tweeters/Woofers, Extended Range Shelf
W66 Merchandised Package – Formula
W73 Entertainment system – Radio, AM/FM Stereo, Compact Disc, Equalizer, 6 Speaker system, Dual Front Door Tweeters/Woofers, Extended Range Shelf
Y81 Merchandised Package – Firebird
Y82 Merchandised Package – Trans Am, Base Coupe
Y84 Merchandised Package – Trans Am
Y87 Merchandised Package – Performance Enhancement
Z28 Merchandised Package – Special Performance
Z49 Canadian Modifications
01U Primary Color exterior, Special
05Q Molding Color, Cyclamen
O5U Primary Color Exterior, Cyclamen
1LE Performance Package Components
101 Interior Trim – Arctic White
1OT Top Color – Arctic White
102 Trim Combination Leather, Arctic White
1OQ Molding Color – Arctic White
1OU Primary Color – Exterior, Arctic White
12B Trim Combination – Cloth, Graphite
12D Trim Combination – Cloth, Graphite
121 Interior Trim – Graphite
14B Trim Combination – Cloth, Dark Gray
1SG Preferred Equipment Group
28U Primary Color – Exterior, Navy Blue Metallic
1FP87- Camaro Coupe Z28
The Millennium Motor: Inside the LS1
Electronic Version, copyright 1996, 1997 by Shark Communications
Adapted from material published on the Vettenet and ZR1 net mail lists in August 1996 and from a printed version in the August, 1996 issue of Corvette Fever magazine
Before the 1997 Corvette was even in dealers, it had been reported for a year or more that the all-new platform, known to insiders as “C5,†would be the first General Motors Corporation product to use a new family of medium-displacement V8 engines. Though the car did not debut on the show circuit until January 6, 1997 and in dealers on March 6. 1997, way back on June 11, 1996 in Los Angeles, GM confirmed the engine rumor with a preliminary to the C5 launch: a press show spotlighting its engine.
My first reaction back then was that what’s known as “RPO LS1, 5.7L SFI V8,†is an outstanding design, engineering and manufacturing exercise destined to be yet another landmark in the history of America’s Sports Car. My second reaction? A snicker at the show biz that clouded the engine’s debut.
It is not unusual to introduce a new Corvette engine before its car. In 1988, media got a comprehensive technical seminar on the LT5 nine months before it was shown the ZR1. Of course, this is now; and that was then.
A major deficiency of this June 11 show and Chevrolet’s other LS1 publicity efforts around the country in the summer of 1996 was that 1) they failed to adequately address the most striking feature of LS1: its pushrod valve gear and 2) they came wrapped in a spoof of medical TV shows. The Corvette community contains many potential C5 customers who were not served well by this program because its information value was degraded by its need to entertain.
The quality and timeliness of the in-depth, LS1, technical information reaching the Chevrolet enthusiast was further blunted by only average coverage to date from Corvette media and Chevrolet’s decision to let Hot Rod magazine break the LS1 story ahead of all other publications. The stories that finally made it into print in the Corvette media were either too brief, poorly researched or lacked depth because their editors felt preempted by Chevrolet’s leaking the story.
These shortcomings of these processes are why you have The Idaho Unofficial Corvette and Corvette Surfing WWW sites. Like a beacon of reality, we’re going to cut through the smoke to the hard-core, gearhead story behind this stunning, new engine.
The LS1 press kit said, “Based on a timeless design by former Chevrolet Chief Engineer Ed Cole, the ‘Gen III’ 5.7-liter V8 marks a bright new chapter in the highly respected lineage that GM small blocks have established in more than 40 years.â€
I think Chevrolet understated its case.
LS1 is brilliant.
Rather than just a chapter in engine history; it’s more like a whole new book!
What it is not is: “based on†Ed Cole’s legendary Small-Block. LS1’s greatness comes from being a clean-sheet-of-paper design. The only major feature it has in common with the Small-Block is a bore center-to-center measurement of 4.40 inches and we believe that exists for marketing reasons rather than an engineering case.
When and Why
By 1991, writing was already on the wall. While tens of millions of Small-Blocks had been produced in 36 years, the basic architecture would be a liability if customer demands for world-class performance, increasingly stringent exhaust emissions regulation and higher fuel economy standards were going to be met. While Chevrolet and the General Motors Powertrain Division (GMPD) knew the Gen II (LT1/4 and L99, introduced for 1992) and Gen I-E (light-truck, Vortec series engines, introduced for 1996) upgrades would stretch the Small-Block’s life; it was clear that further improvement was needed, if those demands were going to be addressed in the late-’90s and early-’00s.
That winter, deep inside GMPD, study began of a third iteration of the Small-Block V8. Expectedly, someone coined the name “Gen III†and it stuck. The project had SAE net power and torque goals of 1 horsepower and 1 pound/foot of torque per cubic inch displacement. There was a weight reduction goal of about 60 lb. When asked about durability, reliability, drivability and pleasability objectives; GMPD said only that intent in those areas was “best in class.†While that phrase was maybe a bit ambiguous, because Corvette has few direct competitors and none with big V8s, my road test of a C5 pilot car (VIN 00063) in March of 1997 showed the new engine exceeds expectations for drivability and meets them for pleasability. I suspect that time will show the engine’s reliability/durability equaling and possibly exceeding that of the Gen II Small-Block.
The first major challenge may have been more philosophical than technical. John Juriga, LS1 Project Manager, talked about the initial design period, “Trying to decide what was the right engine technology for the application was probably the biggest hurdle we faced.â€
This was really not one decision, but a series of them that carried throughout the early phases of the program.
In February of 1993, a stunning decision, arising from this GMPD “soul searching,†was to discontinue Gen III as a Small-Block and do it as a totally new, medium-displacement, V8. The change was made after it became obvious that a Small-Block could not meet the program’s goals; however, don’t think that Gen III work to-date had been for nothing. Significant technology developed for the still-born, Small-Block Gen III went into the 1996 LT4. Roller rocker arms, more aggressive camshaft, hollow-stemmed valves, intake and exhaust port enhancements, rolled-fillet crankshaft and “powdered-metal†rods, all early Gen III ideas, were pulled ahead for the last Small-Block in a Corvette.
Initially, it was thought that the first of the all-new Gen IIIs might show up in a low-volume, 1996 truck application, but as engineers better understood the time necessary to take it from paper to production and make it best-in-class; it was decided that the engine would debut for 1997 in Corvette trim. A similar, but slightly less powerful LS1 goes into the Camaro in 1998 and the all-new, ‘99 or ’00 C/K trucks will get the iron block/aluminum head version. Perhaps other places a Gen III might appear are a “Monte Carlo SS†(front-drive, smaller displacement, aluminum), maybe a high-performance compact truck (iron block/alum. head) and in trucks over of 8600 lbs. GVW and higher (iron block/iron head).
We suspect that the first, very early prototypes of the all-new, Gen III ran on the dynos at GM Powertrain sometime in the early spring of 1993. In-vehicle testing began at the GM Milford Proving Ground in the first week in May of 1993 with the “Chevrolet Engineering and Research Vehicle IV-A†(CERV4a) powered by a prototype, of 5.0 liters and having an iron block and aluminum heads. Eight months later a second car, the CERV4b fitted with a 5.7L iron block/aluminum head Gen III, was added to the test program.
The Gen III passed the “Concept Direction†“gate†in the development process in September of ’93. To do this, it had to have demonstrated the capability to meet the requirements set for the project. Then came Concept Approval. That happened in May of 1994 when the LS1 was within 10% of all development targets.
The C5 “alpha†build, which produced the first prototype cars that were reasonably close to how the 1997 Corvette would look, began in June of 1994. By late-summer, the alpha phase was in high-gear and most all used iron block/aluminum head Gen IIIs at first, with a few all-aluminum units showing up late that year.
The next C5 iteration, the “beta,†began to appear at the end of June 1995. Betas were very representative of what production C5s would be and were the last cars built in Michigan at GM prototype assembly line. Betas used mostly, aluminum LS1s. By fall-’95, the beta build was complete, but the number of cars in testing, believed to have been about two dozen, sometimes exceeded the supply of reliable, all-aluminum engines. Betas not used in development where vehicle mass approximating production intent was necessary, sometimes got iron block/aluminum head engines.
By late 1995 or early 1996, the aluminum block shortage was less of a problem and the LS1 progressed to the point that final development in prototype C5s was underway. That continued into the April of 1996 when the engine was released for production.
An interesting aspect of the engine program was the “Cormaroâ€. In the first six months of 1995, twenty C5 structure/chassis/powertrain combinations were fitted with modified ’95 Camaro bodyshells. These cars were used well into 1996 for powertrain development and were a perfect way to put street miles on the LS1 without drawing attention…at least until ace spyshooter, Jim Dunne, published a picture of a Cormaro in AutoWeek magazine and identified the car as a Gen III V8 “test mule.â€
There was also an unknown number of C4s that were fitted with Gen III engines. These cars were used to develop cold-start ability and the traction control system software.