can someone clue me in to what each engine is that is talked about on these boards and the differences (for example 1LE, LS1, etc.) were these the rpo codes?

 

I dont know alot bout this kinda stuff but to explain it in depth so its easier to undestand this article should help.

LT1 ENGINES
GM's Generation II LT1 engine was introduced in 1992 and first appeared in the 92 Corvette. This engine incorporates a number of innovations not previously seen with the quite popular small block V8. Among these are Optical Spark Control (OPTI-SPARK) and a gear driven water pump. The distributor has been relocated to the front of the engine and the watflow has been reversed as compared to the original small block V8 introduced in 1955.
The drivetrain for 92 included the familiar 700 R4 automatic. The ECM looked identicle to its predecessor, but actually was quite different. The LT1 engine uses an optical spark control system. The distributor incorporates a disc with 360 small holes through which a beam of light is passed, generating electronic pulses. These pulses are counted by the ECM which then fires the spark plugs with much greater accuracy. Base timing is preset when the distributor is installed. Spark advance is controlled by the ECM which monitors the distributor and other engine sensors to determine optimum timing parameters for all load conditions. The information exchanged between the ECM and distributor are not compatible with the earlier HEI magnetic style pickup distributors.

Some of the engine parts can be interchanged with the earlier small block. Among these are the camshaft (92-94 only), the 95 cam has a steel pin which drives the water pump instead of the 92-93 gear drive. The pistons, piston rods, oil pump, crankcase, valve covers, exhaust manifolds, rear oil seal, flywheel and valve train components are interchangeable. The block, heads, timing cover, water pump, timing gears and intake manifolds are not. Accessory mountings such as power steering pump, alternator, AC compressor and harmonic balancer cannot be interchanged. The A.I.R. compressor for emissions is now an electric air pump. The harmonic balancer is a two piece assembly and is the same on the Camaro, Pontiac, Caprice, but different on the Corvette.

There are also some differences between engines in the Corvette, F Body cars, and the Caprice. The Corvette has 4 bolt mains and cast pushrod guides in the aluminum heads. The F Body cars and Caprice have 2 bolt mains. The F Body cars have aluminum heads and the Caprice has cast iron heads.

As you can see the engines, while similar, are quite different than the original SB V8. If you are planning to install a LT1 engine in an earlier model Chevrolet you will find that it will bolt into place with the same engine mounting and that it will also bolt up to any transmission built for a small block V8. Be prepared to change all accessory mounts and accessories ie., AC compressor, alternator, power steering pump, related pulleys and belt tensioning components.

1994 LT1

In 1994 GM introduced sequential port injection for the small block V8. While the engine is essentially the same, GM replaced the "plug in" EPROM "CHIP" with Electrically Eraseable Programmable Read Only Memory (EEPROM). You can no longer install a performance chip in these computers which are now referred to as Powertrain Control Modules or (PCM). These PCM's also electronically control the transmission in addition to engine fuel management functions. The Mass Air Flow Sensor is back in 94. The LT1 also has a MAP sensor. This setup should enhance engine performance significantly. There are also a number of subtle changes which complicate engine swaps. With the new electronic transmissions, the Vehicle Speed Sensor (VSS) is now a Hall effect transfuse which has replaced the pulse generator used in the earlier models.

The new electronic automatic transmissions control shift points (RPM related), hydraulic pressures (firmness of shift). The 95 4L60E incorporates a pulse width modulated signal to control the lockup of the torque converter (seamless transitions).

1995 LT1

The 95 LT1 now has a vent on the distributor to minimize the possibility of condensation forming inside the distributor as a result of a cold water splash, due to its new location in front of the engine. The water pump is now driven by a dowel pin fitted to the front of the cam shaft. The distributor has a modified electrical connector and will not plug into an earlier harness.

1996 LT4

The 96 Corvette, last of the C4 body style, was introduced with a LT4 engine option, available only with the 6 speed transmission. The engine is rated at 330HP/340lb ft Torque. There are a number of performance modifications incorporated in this engine. Modifications include 2.00" Intk, 1.56 Exh Valves, a camshaft with enough overlap to eliminate the requirement for a EGR valve, Higher Compression heads (10.75:1), 1.6 aluminum rocker arms, and sodium filled valve stems. The Red Line is now 6200 RPM. The heads on the LT4 flow 240 CFM as compared to the LT1 heads at 195 CFM.

1997-XX GEN III LS1

The Corvette aluminum block LS1 345HP(5600RPM) / 350lbs-ft(4400RPM) of torque is the 3rd generation small block. The engine features cross bolted (6 bolt) main bearing caps, aluminum cylinder heads (10.1:1 CR), a hollow hydraulic roller cam, 3.9"bore x 3.62 stroke, tuned composite intake, individual ignition coils for each cylinder and a roller timimg chain. FIS has harnesses and calibrations available for these engines for any retrofit application.

The 98 plus F-Body cars have a LS1 engine option, this engine is almost identical to the Corvette but is rated 305HP at 5200 RPM and 335 lbs ft Torque at 4400. The engines are identicle with the exception of Accessory mounting and emissions components. A forced air package on the F-Body cars increases this rating.

 

on your car...what is ws6?

 

WS6 is the Firebird performance package the same as the Camaro IROC or Z28 option. In your original post, 1LE is a performance RPO code and has nothing to do with engines.

All GM engines have a letter code designation. Most are just general purpose, mild engines.

LG4, LU5, L69, LB9, L98, L03 are the V8's offered in third gens.

LQ8, LQ9 are the 4 cylinder Iron Duke Pontiac engines that were offered.

LC1, LB8, LH0 are the V6's.

Over the years GM has produced many engine combinations. Only a few are considered true performance engine and that's the ones you always hear about. The most famous is the 1969 ZL-1 all aluminum 427 BBC.

Now the LT1, LT4 and the new LS1 and LS6 are the most popular engines to use for performance.

 

i see, so how do i find out what engine i have?
i bought the car and all i know is that it is a 5.7L 350

 

well, for one, the engine is not stock if its a 86 TA
secondly, what type of fuel induction setup does it have?

 

As mentioned above, if it's a 350 then it's not stock. GM never offered the 5.7L in a third gen until 1986 and then there were only a couple that made it off the assembly line. It wasn't until 1987 that the 5.7L was an option. The 5.7L is called the L98.

If the engine is still original then it's a 305 and could be a LG4, L69, LB9. It depends what fuel system is on the engine and what tranny is in it.

 

LG4 - carburated 305, non HO, base V8 (1982 to 1987)
L69 - carburated 305, High Outpout V8 (1982 to 198?)
LU5 - Cross Fire Injection (CFI) 305 (1982 to 1984)
LB9 - Tuned Port Injection (TPI) 305, High Outpout V8 (1985 to 1992)
L98 - Tuned Port Injection (TPI) 350, High Outpout V8, (1987 to 1992)
B4C - Tuned Port Injected (TPI) 350, High Outpout V8 (late 80's to 92, Police Package Camaro)
LO3 - Throttle Body Injection (TBI) 305, non HO, base V8 (1988 to 1992)

then you got u'r sixers.. all i know about them is LC1 which is what the Turbo T/A in 1989 had (3.8 buick turbo)

i think the codes were LB8, LH0 and a few more (yay, copy paste) for the other v6's.. (2.8 Multi point Fuel Injection, 2.8 carb and a 3.1L..)

Noteworthy Engines
LS1 - Fuel Injected Tuned Port, Alluminum Block... high tech guizmo if you ask me.. found 98 to present camaro z28's and SS.... also in 98+ Firebird Formula, Trans Am, Firehawk.

LS6 - same as LS1 but with diff. Heads, cam and composite intake (give or take a few minor things).. (same production years as LS1)

LT1(second gen) - iron Block aluminum head, reversed cooled (enters heads first insted of block). from 93 to 97 in Z28's, SS, Formula, Trans Am, Firehawk.

LT1(first gen) - a nice 350 found in camaro's of the late 60's early 70's..

ZR1 - 32 valve, DOHC 350.. 16 runner TPI (for higher revs).. technologically advanced for it's time, found in corvette between the years 1989 to 1995).. rare..

ZL1 - all aluminum big block 427 cid.. lendgendary.. late 60's camaro.

i think the engine code for a 454 SS chevelle is LS6 as well..

L88 corvette, 454cid

 

wow thats a lot of info. thx. anyway for my engine it is a 5.7L carbed engine...anyone know if gm just puts out a basic 350 longblock... actually it think it may have been a crate engine because the engine is painted blue along with the intake manifold and heads and valve covers.

 

another question...what is the police package.
i think i remember reading a tech article on this site that explained it but i cant find it.

 

police package is option code B4C, it came out in the later years of thirdgens, possibly only 91-92 and i think it was only on RS models. it had a tranny cooler. that's about all the specifics i know, someone else will chime in though.

 

.Not to nitpick but, ZR-1 was the suspension designation and the engine in that Vette was deignated the LT-5.

 

The L-88 was a 427. Offered in 'Vettes in '67, '68 and '69. The ZL-1 was an aluminum blocked version of the L-88.

The 1970 Chevelle SS 454 was available in 360 horsepower (LS-5) which was a cast-iron intake and Quadrajet carb version.

The other 454 was the LS-6 (450 horsepower) with aluminum intake and Holley carb.

Very little interchanged between the two engines (meaning the factory parts were different throughout the engines).

There was a 375 horse 396 (402) offered in '70 (L-78) in the Chevelles and Camaros.

L-78 was also a very popular choice in the '66 to '69 SS Chevelles, '67, '68 & '69 Camaros, and the '68 & '69 Novas. This was a true 396 engine. There were aluminum-headed versions of the L-78 which became L-89.

The 350 LT-1 was first available in the new style 1970 Z-28 Camaro (along with the same year 'Vette) and lasted through '73 in a much watered down form.

There are other 'well-known' codes (including the L-79 327s at 350 horsepower-very strong little engines) and many other lesser known codes from the '60s on to today.

jms

 

Demon,

You might want to find the RPO label on your car. On an '86, it is probably in the center console. It should look like this:



The VIN is also a good hint for the basic equipment. You'll find that in numerous places, most prominently on the upper dash pad visible through the windshield.

Once you find your RPO codes, you can check your equipment against this list:

RPO Codes.pdf

(You'll need Adobe Acrobat Reader 4.0 to open the file.)

If your engine is blue, it may be an older GM "corporate" engine from the late '70s or early '80s, or a reman/crate engine. The best way to determine what you have is to check the casting numbers on the rear ledge of the case near the distributor:



You can chek the numbers you find at Mortec.com to identify what you have.

 

well you know what a thirdgen looks like under the hood. what do i have to do to get to those numbers? do i have to remove the engine?

 

use both hands a mirror and a flash light... LOL

zroc