Todays engine vs. yesteryears.

[Cranky1]

In the last few months I have a quite a few people ask how I like my Silverado C1500. 1 st question they ask is how I like the 5.3 L engines performance and fuel mileage. I tell them that I love the performance and can't believe the fuel mileage that it gets compaired to the 327 small block I had in my 1970 camero 20 years ago.

 

I have had 3 people refer to the 4.8 as the LT1 and 2 people refer to the 5.3 as the LS1. Did I go into a 20 year deep freeze sleep and miss some thing some where?

 

I know I took a break from the muscel car days to raise a family and run a business. I'm not up on new engines to ask if they are on crack to start an argument, but this doesn't seem right. I remember years ago people thought they had a LT1 because it was a 350 ci small block with a 4 bolt main, and they found some big valve heads (202) and bolted them on and "presto" an LT1..lol..

 

Is there any simularity in the LM7 to a LS1 or is this just people miss informed and assuming this. Sorry if this has been brought up before, but I would really like to know for the record.

[BADGERMAN]

As far as I know, the LT1 is 350 engine that started in the 92' corvette and 93' camaro's, firebirds and transams. The LS1 I think came out in about 98' or 99' corvettes and camaro's. (I not excatly sure about the years, but they are close)

 

The LT1 and LS1 motors where 350's and very tuff motors.

 

I put a 93' LT1 and 6 speed tranny in a 67' chevelle and it turn some pretty good numbers for a stock motor.

 

In a 3500 pound car in ran low 13's at about 103 mph.

[Pewter Pro-Tec]

The LS1 is considered to be in the Gen III family of small-block V-8 engines. The LT1 is the classic 350 small block that is made of legend and I think it's considered Gen II.

 

The Gen III family of V8's includes the 4.8, 5.3, 6.0 used in the trucks, and also the 5.7 LS1 used in the 98 F-bodies (Camaros and Firebirds) and Vettes. I think it also includes the aluminum LS6. I'm not to sure when the LS1 started replacing the LT1 but I think BADGERMAN is right, it was about 98 or 99.

 

The Gen IV family includes the LS2 in the 05 Vette and SSR trucks and the mighty LS7 in the '06 Z06 Vette.

 

In the short span that the Gen III engines have been in production, they have gained a very large following because of the ease of adding power to these engines. These guys are the Gods of Gen III and IV engine performance-LS1 Tech You can make stupid power with bolt-ons and these engines respond well to forced induction.

 

Also, every engine in the Gen III family will drop into your truck, I think the Gen IV engines have relocated cam sensors but I don't see why they wouldn't fit as well. I love my Gen III engine and I am pretty confident that they will give the legendary 350 small-block everybody knows and loves a run for its money in terms of being a great engine.

 

BTW, technically your 5.3 is considered to be an LM7, not an LS1.

[99-2door]

OK

 

The modern LT1 was found in 92-96 Corvette and 93-97 F-bodies, and also some B-bodies. There was an upgrade version called the LT4 that was found in some 96 Corvettes and 97 Camaro SS. These are GEN II motors, reverse coolant flow, some iron heads, some aluminum.

 

The LS1 intro-ed in the 97 Corvette and 98 f-body. Gen III motors, aluminum block and heads.

The current truck motors(5.3L, 4.8L, 6.0L) are based on the same architecture as the LS1. They have cast block and aluminum heads. These engines together are sometimes referred to collectively as LS or LS1 engines, when they should really be called GEN III.

 

What you were thinking of was the LT1 which was a solid lifter 350 found in ZR1 Corvette 70-72. It was a GEN I engine. There was also a ZR-1 Corvette in 90-95 that had a LT5 DOHC engine.

[Cheekster96]

not that this matters..but here is some more info...

the LS1s werer 346 CI and all aluminum whereas the LT1s only had aluminum heads and cast iron block and were a truck 350 CI.

The motors that came in the Caprices were a smaller version called L99 i think and were a 4.3L size (V8).

Also, the vettes that had the LT1 had four bolt mains and the F Bodies had the 2 bolt mains.

just like any line of GM engines, they are get upgraded or replaced at one time.

The L98 (250 hp in 91 Vette) got replaced by the LT1 (300 hp in 92 Vette) which got replaced by the LS1 (340 hp in 97 Vette).

Then there is the LS2 (400 CI C6 Vette and GTO and SSR motor in 400 hp trim).

Looking forward to the new LS7 that comes out in the ZO6 Vette. Claimed 500 hp.

Current truck motors i think were designed from the LS1 Vette motors. Just downsized but kept the characteristics of the head design. Six bolt mains, aluminum heads but are cast iron blocks where the cars have aluminum.

Hope I didnt ramble on too much or repeat somebody else..

Later all.

Lee

[millerwd]

Just a word of caution, don't make a bet that ONLY the 1970 ZR1 Corvette had the LT1.

The LT1 was part of the ZR1 RPO , it included: M22 transmission, heavy-duty power brakes, transistor ignition, special aluminum radiator, special springs and front and rear stabilizer bars. There were only 25 ZR1s produced in 1970, while there were 1287 units with the LT1 RPO. Trueley an amazing engine for it's time at 350 cubic inches it produced 370 horespower.

 

There's the facts from the Corvette Black Book.

[lrymal]

...an amazing  engine for it's time  at 350 cubic inches it produced 370 horespower....

<{POST_SNAPBACK}>

 

 

I'm curious. Could someone check on this. In the mid to late 70s, just prior to the introduction of computer assistance on the motor, the choking done by EPA devices, knocked the 'Vette's motor down to 170 horsepower?

 

I remember that from something... Bad dream of me yuth???

[snoman]

...an amazing  engine for it's time  at 350 cubic inches it produced 370 horespower....

<{POST_SNAPBACK}>

 

 

I'm curious. Could someone check on this. In the mid to late 70s, just prior to the introduction of computer assistance on the motor, the choking done by EPA devices, knocked the 'Vette's motor down to 170 horsepower?

 

I remember that from something... Bad dream of me yuth???

 

<{POST_SNAPBACK}>

 

 

 

 

 

Prior to 1973 they had a lot more HP especailly 70 and before. They had some very radically cammed engines back then and some of them where underrated a good bit. There was a 327/365 HP that ran well. THen there was the 68 Z28 302 that while rated at 290 HP for insurance reasons easily put out over 400HP stock and pulled like mad from about 4500RPM to the redline past 8000RPM. While todays engines have some power they still pale compared to some of the engines of the 60's. Our biggest problem then was getting the power down to the ground with tires of the era in those heavy cars not lack of HP. Todays cars have better tires and weigh less. I had a friend that had a GTO with a slightly warmed 389 tri power that was down right scary. Even with wide street tires it would only do low 14's because it could not hook up good at WOT until 3 gear with a 4sp but throw on a set of slicks back then and that "goat" would easily run in the hi 12's on a 1/4 mile. I had a cousin who had a 65 Pontiac Catalina with a factory 421 tripower with factory 4.11's and a 4 sp it is was a trip too. I remember when raw power was the norm and rode in and drove several of them back then.

[Cheekster96]

wasnt the LT-1 of the 70s vette for off road use racing only?

Horsepower was rated differently in those years up till about 73 i think.

SAE vs NET horsepower.

the horsepower ratings today are generated with everything attached to the engine..ie, water pump, alternator, ps pump, etc etc. im not sure if this is the SAE or NET rating.

the other way that horsepower was generated was with only the engine turning with no accesories.

so, imagine if you will, todays Vortec 8100 makes something like 345 hp (correct me if im wrong) where as the 454 that came out in 73 only made 230.

the 427s in the vettes from 66-69 made upward of 430 hp (but closer to 500 or more to get away from the insurance companies) and todays LS2 is pushing 400hp.

still, awesome numbers either way..i wouldnt mind having either vette but for now, i ll keep my Z28/SS and have fun with that!

Lee

[snoman]

wasnt the LT-1 of the 70s vette for off road use racing only?

Horsepower was rated differently in those years up till about 73 i think.

SAE vs NET horsepower.

the horsepower ratings today are generated with everything attached to the engine..ie, water pump, alternator, ps pump, etc etc.  im not sure if this is the SAE or NET rating.

the other way that horsepower was generated was with only the engine turning with no accesories.

so, imagine if you will, todays Vortec 8100 makes something like 345 hp (correct me if im wrong) where as the 454 that came out in 73 only made 230.

the 427s in the vettes from 66-69 made upward of 430 hp (but closer to 500 or more to get away from the insurance companies) and todays LS2 is pushing 400hp.

still, awesome numbers either way..i wouldnt mind having either vette but for now, i ll keep my Z28/SS  and have fun with that!

Lee

 

<{POST_SNAPBACK}>

 

 

 

 

You have not riden in a Z28 until it you have riden in a 68 or 69 with a 4.10 or 4.56 axle and a close ratio gearbox. You place too much on the 73 rating because in 70 the had a 454/465HP that was easily 500HP and Pontiac made problay some of the most powerful engine ever put in cars in the mid 60's along with just about bullet proof rear ends too. I grew up hot rodding the late 60's cars and it was a whole differnt world then engine wise. Yes they rate them differntly today but I thinkl they are sometimes inflated for advertising in the HP wars.

[99-2door]

The motors that came in the Caprices were a smaller version called L99 i think and were a 4.3L size (V8).

 

<{POST_SNAPBACK}>

 

 

 

Nope,

Some Caprices had the "baby LT1" that was the 4.3L V8. But some of them had the 5.7L v8. I have one in my shop right now that does. They also came in other b-bodies like the Impala SS and Roadmaster.

[99-2door]

...an amazing  engine for it's time  at 350 cubic inches it produced 370 horespower....

<{POST_SNAPBACK}>

 

 

I'm curious. Could someone check on this. In the mid to late 70s, just prior to the introduction of computer assistance on the motor, the choking done by EPA devices, knocked the 'Vette's motor down to 170 horsepower?

 

I remember that from something... Bad dream of me yuth???

 

<{POST_SNAPBACK}>

 

 

 

 

Yeah the base engines took a big HP hit due to Smog control

75 165HP

76 180HP

77 180HP

78 175HP

79 195HP

and in 80 in CA it was sold with a 305 at 180 HP

[Cheekster96]

The motors that came in the Caprices were a smaller version called L99 i think and were a 4.3L size (V8).

 

<{POST_SNAPBACK}>

 

 

 

Nope,

Some Caprices had the "baby LT1" that was the 4.3L V8. But some of them had the 5.7L v8. I have one in my shop right now that does. They also came in other b-bodies like the Impala SS and Roadmaster.

 

<{POST_SNAPBACK}>

 

 

 

 

was there an option for the caprices to have the 350 LT1 as well? i knew they offered the 4.3L version. the real Impala SS had them but with cast iron heads instead of aluminum.

anybody know what the numbers (hp/torque) were for that 4.3L V8?

[Scyry]

My Mom's 1978 Corvette is rated at 220 HP, 350 in it.

[99-2door]

The motors that came in the Caprices were a smaller version called L99 i think and were a 4.3L size (V8).

 

<{POST_SNAPBACK}>

 

 

 

Nope,

Some Caprices had the "baby LT1" that was the 4.3L V8. But some of them had the 5.7L v8. I have one in my shop right now that does. They also came in other b-bodies like the Impala SS and Roadmaster.

 

<{POST_SNAPBACK}>

 

 

 

 

was there an option for the caprices to have the 350 LT1 as well? i knew they offered the 4.3L version. the real Impala SS had them but with cast iron heads instead of aluminum.

anybody know what the numbers (hp/torque) were for that 4.3L V8?

 

<{POST_SNAPBACK}>

 

 

 

 

Yes, the 9C1 Caprice's had the 5.7L LT1 as well as some regular production Caprices