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Last GM big block rolls off the line.


lothos

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http://www.buffalonews.com/home/story/899075.html

It was the last of the “big block” V-8 engines made by the plant, a legacy dating to 1958 and a local connection under the hood of some renowned GM cars.

The end of the L18 on Friday also puts 150 hourly workers on layoff, bringing to 298 the total number of workers on layoff from the Tonawanda plant.

WARNING: I'm a total car newbie, don't be surprised if I ask a stupid question! Just trying to learn.

Cheers!

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Yeah... I read that yesterday.

I have had a bunch of the Big Blocks, down theu the years.

I have always had a soft spot for them.

I loved the huge amounts of tire smoking torque they could make. :D:D:D:D

A little turbocharged, 4 cylinder, sewing machine motor, can never equal what a 427 or 454 was.

A lot of people will miss them...me included.

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A little turbocharged, 4 cylinder, sewing machine motor, can never equal what a 427 or 454 was.

A little engine can never equal a real motor. It doesn't even matter if it has the same torque or horsepower, can't compare the caracteristics between an engine and a 4-banger.

Hopefully a true Cadillac V8 will return in the future!

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Where does this leave the northstar? Is that considered a big block?

WARNING: I'm a total car newbie, don't be surprised if I ask a stupid question! Just trying to learn.

Cheers!

5% discount code at RockAuto.com - click here for your discount!

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The Northstar is only 280 ci.

It is a small engine...compared to any of the big blocks.

The big blocks started in 1958 with the 348...and progressed up to 495 cubic inches. (8.1 liter)

Thru the years there was the 348, 366, 396, 402. 409, 427, 454, and the 495.

After a half century...they are no more.

The good thing is, there are several aftermarket makers of the big blocks.

They are actually better in a lot of ways than the factory engines.

LONG LIVE THE BIG BLOCK.

:D:D:D:D

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The Northstar is only 280 ci.

It is a small engine...compared to any of the big blocks.

The big blocks started in 1958 with the 348...and progressed up to 495 cubic inches. (8.1 liter)

Thru the years there was the 348, 366, 396, 402. 409, 427, 454, and the 495.

After a half century...they are no more.

The good thing is, there are several aftermarket makers of the big blocks.

They are actually better in a lot of ways than the factory engines.

LONG LIVE THE BIG BLOCK.

:D:D:D:D

What about the Cadillac 500 ci (8.2 L) from the 70s? B) Isn't that the big block of (production) big blocks, so to say (in other words, the Cadillac of big blocks :))? Or is it a different series of engines than the one mentioned above?

Edited by hjb981
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There was a truck version with 0.4 inches higher decks. It was made in 366, 427, and 454 cid versions. The "truck 427" block was preferred by some more aggressive engine builders because its higher decks allowed more stroking. The high deck may also be used in the factory engines with more than 454 cid.

The 348/409 and the Mark IV crankshafts were interchangeable. If you want a 3.25" or 3.5" stroke in a big block, get a 348 or 409 crankshaft. The rods and pistons are your problem, though. I'm sure that there were a lot of small differences, but the main design difference between the 348/409 was the head and combustion chamber. The 348/409 head was flat with no combustion chamber; the piston had the combustion chamber in it. It was a "wedge" engine like the SBC. The big block had a modified hemi combustion chamber with a small squish area over one side, with valves canted to accommodate the combustion chamber shape and minimize shrouding, and the ports were swoopy things that encouraged tuning the intake path. Each valve stem was parallel to only one other valve stem on the head, which caused somebody to give this engine the name "porcupine." This design was mimicked by the Ford Cleveland Boss 302, 351C, and 400C, and in the 460 and related engines and others.

A big advantage of the bowtie big block engines was the cooling. While the Mopar 426 went out of warranty if you held it at full throttle for more than 17 seconds, the Chevy 427 was rated for marine use -- full output for long periods of time. The 495 cid aluminum version weighted 200 pounds less than the iron 454 and was used in the Chapparal, dragsters, racing speedboats of several kinds, and a supercharged 850 hp version was even used as a general aviation engine. Also, in every big block that I had, the oil would stay clean for several thousand miles, telling me that the oil was kept cooler than in other engines too.

There was a 509 cid version sold by GM Performance Parts that they called the "510" for some reason. Right now they still sell two versions of a 502 (450 hp and 502 hp), and also a 620 hp version with 572 cid. With the Tonowanda plant closing that line, when the stock is gone there will be no more of those motors from GM.

World Castings and others make GM big block clones, as Texas Jim says, so this motor will live on. For now, its place has been taken by the tall-deck LS engine, which is about 250 pounds lighter and more fuel efficient, and is built just as strong as the Mark IV-VI.

CTS-V_LateralGs_6-2018_tiny.jpg
-- Click Here for CaddyInfo page on "How To" Read Your OBD Codes
-- Click Here for my personal page to download my OBD code list as an Excel file, plus other Cadillac data
-- See my CaddyInfo car blogs: 2011 CTS-V, 1997 ETC
Yes, I was Jims_97_ETC before I changed cars.

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The Northstar is only 280 ci.

It is a small engine...compared to any of the big blocks.

The big blocks started in 1958 with the 348...and progressed up to 495 cubic inches. (8.1 liter)

Thru the years there was the 348, 366, 396, 402. 409, 427, 454, and the 495.

After a half century...they are no more.

The good thing is, there are several aftermarket makers of the big blocks.

They are actually better in a lot of ways than the factory engines.

LONG LIVE THE BIG BLOCK.

:D:D:D:D

What about the Cadillac 500 ci (8.2 L) from the 70s? B) Isn't that the big block of (production) big blocks, so to say (in other words, the Cadillac of big blocks :) )? Or is it a different series of engines than the one mentioned above?

I believe that the 472, the 500 and later the 425 were all considered big blocks.

But Cadillac built it's own engines, in their own assembly plant and the Cadillac engines had no relation to the Big Blocks of Chevy and GMC.

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I believe that the 472, the 500 and later the 425 were all considered big blocks.

But Cadillac built it's own engines, in their own assembly plant and the Cadillac engines had no relation to the Big Blocks of Chevy and GMC.

Yes, I thought so also. Does anyone know any trivia about those engines, or in which ways they were different from the Chevy big blocks?

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I think that all OHV iron Caddillac V8s are considered big blocks. There were really only two designs, 1949-1962 and 1963-1984. The displacements were 331 cid, 364 cid, 389 cid, 429 cid, 472 cid, 500 cid, 425 cid, and 368 cid. I don't know where it was made but even if it's in the Tonawonda plant it wasn't the same line as the Mark IV-VI bowtie big-block.

A 427 cid version of the 409 big block was available in a special high performance, aluminum block and heads, in 1963; according to Wikipedia 50 were made. Another version of this engine made an appearance in NASCAR in 1963 as the "mystery motor" at Datona. Some think that the "mystery motor" had the porcupine heads and was basically a prototype of the Mark IV, some say it was a stroked 409. Amazingly, even at this late date there seems to be no reliable information on the matter. What is known is that the Mark IV was first designed as a 427 but was introduced in 1965 with a reduced bore to keep it under 400 cid (the "396") because of some irritated Congressmen and the massive market share of GM in the early 1960's.

Chrysler's big blocks began with the 331 cid hemi in 1951. The large bore distance was increased further for a second generation beginning in the 1958 model year. The famous 426 version of this motor was made by Mercury Marine, as was the famous DOHC V8 used in the first Corvette ZR-1.

CTS-V_LateralGs_6-2018_tiny.jpg
-- Click Here for CaddyInfo page on "How To" Read Your OBD Codes
-- Click Here for my personal page to download my OBD code list as an Excel file, plus other Cadillac data
-- See my CaddyInfo car blogs: 2011 CTS-V, 1997 ETC
Yes, I was Jims_97_ETC before I changed cars.

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