GM engine gurus, come in.
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From: Fort Knox, KY
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GM engine gurus, come in.
Did the ORIGINAL LT-1 engine debut in the Corvette or the Camaro? What was it's significance? Surely it wasn't the first small-block engine produced by the General that generated more than 300 hp was it? :confused:
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Re: GM engine gurus, come in. (onedef92)
I don't know if the LT-1 in F-body was the same as in Y-body, but based on the L98 I'd say they differed; the Corvette was the flag ship so a debut is likely there.
The LT-1 was another step in engine evolution, though perhaps not quite as revolutionary as the L83 (1st EFI) or even the L98 (port injection EFI).
The Y-body LT-1 was at least the 1st EFI >=300HP; didn't the old 327 boast over 300hp too (though a different rating system).
This should be an interesting and informative post.
The LT-1 was another step in engine evolution, though perhaps not quite as revolutionary as the L83 (1st EFI) or even the L98 (port injection EFI).
The Y-body LT-1 was at least the 1st EFI >=300HP; didn't the old 327 boast over 300hp too (though a different rating system).
This should be an interesting and informative post.
Le Mans Master
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From: Thornton CO
Re: GM engine gurus, come in. (onedef92)
If you are talking about the LT-1 that came out in 1992 then yes it did differ form the FBody. The Fbody introduced it in 1993 with 275hp due to different exhaust (I think). Also, I believe the Fbody only had 2 bolt mains while the Vette had 4 bolt. I could be wrong on that.
Instructor
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From: Sheboygan WI
Re: GM engine gurus, come in. (GRX)
Thinking since the HP in orig. post was 300 sounds like LT1 .
LT-1 was 1970 with 370 HP .
Only know this because i remember reading a post about the importance of the "-" . ( engine guru imposter :troll )
#'s are black book . Is this right ?
:seeya
LT-1 was 1970 with 370 HP .
Only know this because i remember reading a post about the importance of the "-" . ( engine guru imposter :troll )
#'s are black book . Is this right ?
:seeya
Drifting
Joined: Jan 2001
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Re: GM engine gurus, come in. (GRX)
The original LT1 was a Corvette only engine, however the LT1 was very close to the original Z28 DZ302 engine that appeared in the Camaro's first. Its all how you look at it. In 92 the LT1 reappeared in the Corvette followed by a similar but not the same LT1 in the Camaro, Buick Roadmaster, and the Caprice.
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From: San Pedro CA
Re: GM engine gurus, come in. (snaketr)
ok... here goes nothing...
The original LT-1 was back in 1970 or so... 370 SAE GROSS hp... in 1972, it became 270 or so... and by 74, it was gone... high compression, carbs and low octane did not mix well...
there are at least 5 versions of the LT1!!!!
A 265ci version, all iron, in the Caprice
A 350ci version, all iron, in the Caprice and cop cars.
A 350ci version, all iron, in the Impala SS and some cop cars.
A 350ci version, iron block, alumium heads, 2 bolts - Fbody
A 350ci version, iron block, alumium heads, 4 bolts - Vette
The main performance difference between the Vette's and the Fbody was exhaust... there is a minor cam phasing, but not enough to matter.
The original LT-1 was back in 1970 or so... 370 SAE GROSS hp... in 1972, it became 270 or so... and by 74, it was gone... high compression, carbs and low octane did not mix well...
there are at least 5 versions of the LT1!!!!
A 265ci version, all iron, in the Caprice
A 350ci version, all iron, in the Caprice and cop cars.
A 350ci version, all iron, in the Impala SS and some cop cars.
A 350ci version, iron block, alumium heads, 2 bolts - Fbody
A 350ci version, iron block, alumium heads, 4 bolts - Vette
The main performance difference between the Vette's and the Fbody was exhaust... there is a minor cam phasing, but not enough to matter.
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Team Owner
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From: San Pedro CA
Re: GM engine gurus, come in. (snaketr)
1972 was the last year for the LT1, the L-83 replaced it in 73 which was a hydralic lifter.
The L83 came out in 1982 as the crossfire...
Pro
Joined: Feb 2002
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From: Houston Tx
Re: GM engine gurus, come in. (onedef92)
If you are referring to the LT1 (like the one in your Vette), Yes, they appeared in the Vette in 92 First, then in the Fbody (Camaro) in 93 , though they had different cam and exhaust and 2 bolt main end caps.
This engine is significant for several reasons. First , it was the first real "second generation" small block Chevy. It has reverse cooling (cooling the heads first) and distributorless ignition (optispark). It has (in the Vette), synthetic oil from the factory as well as the Dexcool coolant and 100k plugs. The 300hp mark was the desired (and acheived) target because the engineers wanted to top the previous small block production high mark, the 1970 LT-1, then rated at a gross 370 hp . When actually dyno'd , these early engines did not quite make 300 hp net. So, the new LT1 is actually more powerful than the LT-1 of old. These engines are strong , powerful , easy to modify and reasonably inexpensive.
Hope that helps..... :seeya
This engine is significant for several reasons. First , it was the first real "second generation" small block Chevy. It has reverse cooling (cooling the heads first) and distributorless ignition (optispark). It has (in the Vette), synthetic oil from the factory as well as the Dexcool coolant and 100k plugs. The 300hp mark was the desired (and acheived) target because the engineers wanted to top the previous small block production high mark, the 1970 LT-1, then rated at a gross 370 hp . When actually dyno'd , these early engines did not quite make 300 hp net. So, the new LT1 is actually more powerful than the LT-1 of old. These engines are strong , powerful , easy to modify and reasonably inexpensive.
Hope that helps..... :seeya
Le Mans Master
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From: Atlanta GA
Re: GM engine gurus, come in. (Shriker)
It was also (one of?) the first to use sequential injection - i.e. each injector fires independently of one another as the cylinder requires it. TPI has "bank fire" in that all the injectors on the drivers side fire, then on all on the pass side fire.
Drifting
Joined: Jun 2001
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From: Lake Ozark MO
Re: GM engine gurus, come in. (Shriker)
Sorry Shriker.. The Vette didn't go distributorless until '97. The LT1 used the Optispark which was a cam driven, optical (dual optical actually, computer-wise) ignition system.
Nothing too extraordinary.. my '85 ZX Turbo used a similar setup.
The Optispark is the subject of many complaints, but overall it's a very good setup.
Nothing too extraordinary.. my '85 ZX Turbo used a similar setup.
The Optispark is the subject of many complaints, but overall it's a very good setup.
Melting Slicks
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From: NW Chicago Suburbs
Re: GM engine gurus, come in. (onedef92)
The Camaro/F-bird's LT1 is exactly the same as the Corvette LT1 with one exception, the Vette has 4 bolt mains. From the throttle body to the exhaust ports the engines are identical (except the 4 bolt/2bolt mains). Same cam, same heads, pistons, etc.
The iron headed LT1, found on Impala, Caprice, Roadmonsters and Fleetwoods is exactly the same as the Camaro/F-bird LT1 except the heads are iron, the valve springs are smaller and the cam has less lift/duration. Otherwise the engines are the same from the throttle body to the exhaust ports.
There are differences in the intake plenums and exhaust manifolds that account for some of the power differnces between Camaro/F-bird LT1 and the Vette LT1, but if you bolt a Camaro LT1 into a Vette, you'll never be able to tell the difference, it'll make the same HP/torque. Add the Vette/Camaro cam to an iron headed LT1, upgrade the springs and it'll make the same power as a Vette LT1, just weighs about 50lbs more (the iron heads vs aluminum).
Eric
[Modified by silver & red CE, 7:57 AM 10/19/2002]
The iron headed LT1, found on Impala, Caprice, Roadmonsters and Fleetwoods is exactly the same as the Camaro/F-bird LT1 except the heads are iron, the valve springs are smaller and the cam has less lift/duration. Otherwise the engines are the same from the throttle body to the exhaust ports.
There are differences in the intake plenums and exhaust manifolds that account for some of the power differnces between Camaro/F-bird LT1 and the Vette LT1, but if you bolt a Camaro LT1 into a Vette, you'll never be able to tell the difference, it'll make the same HP/torque. Add the Vette/Camaro cam to an iron headed LT1, upgrade the springs and it'll make the same power as a Vette LT1, just weighs about 50lbs more (the iron heads vs aluminum).
Eric
[Modified by silver & red CE, 7:57 AM 10/19/2002]
Melting Slicks
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From: NW Chicago Suburbs
Re: GM engine gurus, come in. (dtorc4)
It was also (one of?) the first to use sequential injection ....
Eric
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Re: GM engine gurus, come in. (Shriker)
If you are referring to the LT1 (like the one in your Vette), Yes, they appeared in the Vette in 92 First, then in the Fbody (Camaro) in 93 , though they had different cam and exhaust and 2 bolt main end caps.
This engine is significant for several reasons. First , it was the first real "second generation" small block Chevy. It has reverse cooling (cooling the heads first) and distributorless ignition (optispark). It has (in the Vette), synthetic oil from the factory as well as the Dexcool coolant and 100k plugs. The 300hp mark was the desired (and acheived) target because the engineers wanted to top the previous small block production high mark, the 1970 LT-1, then rated at a gross 370 hp . When actually dyno'd , these early engines did not quite make 300 hp net. So, the new LT1 is actually more powerful than the LT-1 of old. These engines are strong , powerful , easy to modify and reasonably inexpensive.
Hope that helps..... :seeya
This engine is significant for several reasons. First , it was the first real "second generation" small block Chevy. It has reverse cooling (cooling the heads first) and distributorless ignition (optispark). It has (in the Vette), synthetic oil from the factory as well as the Dexcool coolant and 100k plugs. The 300hp mark was the desired (and acheived) target because the engineers wanted to top the previous small block production high mark, the 1970 LT-1, then rated at a gross 370 hp . When actually dyno'd , these early engines did not quite make 300 hp net. So, the new LT1 is actually more powerful than the LT-1 of old. These engines are strong , powerful , easy to modify and reasonably inexpensive.
Hope that helps..... :seeya
Pro
Joined: Feb 2002
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From: Houston Tx
Re: GM engine gurus, come in. (Dan Parker '96)
Sorry Shriker.. The Vette didn't go distributorless until '97. The LT1 used the Optispark which was a cam driven, optical (dual optical actually, computer-wise) ignition system.
Nothing too extraordinary.. my '85 ZX Turbo used a similar setup.
The Optispark is the subject of many complaints, but overall it's a very good setup.
Nothing too extraordinary.. my '85 ZX Turbo used a similar setup.
The Optispark is the subject of many complaints, but overall it's a very good setup.
Although many complain about the opti, it is actually a good design, and had the original vent/drain hole been sized correctly , like the engineers designed it (and was later resized to ) the reputation would not be quite so bad. The newer opti's are quite reliable and accururate. :seeya
Melting Slicks
Joined: May 2001
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From: San Diego CA
Re: GM engine gurus, come in. (Shriker)
Sorry Shriker.. The Vette didn't go distributorless until '97. The LT1 used the Optispark which was a cam driven, optical (dual optical actually, computer-wise) ignition system.
...
You are correct, Dan, but I was actually referring to the fact that the opti is not like a typical distributor in a standard sense. I should have been more clear...
...
You are correct, Dan, but I was actually referring to the fact that the opti is not like a typical distributor in a standard sense. I should have been more clear...
Pro
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From: Houston Tx
Re: GM engine gurus, come in. (John Row)
Since I'm never one to let sleeping dogs lie, the Vette went distributorless in 90 with the LT5.