2 questions in one thread (if allowed)

[hellonwheelz3]

Can someone tell me what A/T R/T and the other letterings mean in the car model descriptions? I've seen previous threads but can't find them.

Secondly, and this is a dumb one, can someondo list the sizes of big block engines versus small block? Thanks an bunch

[Keef]

any particular car manufacturer or are you looking for engine sizes for all big and small blocks ever made?

[Patrick2005]

I read somewhere that a "big block" is an engine over 400 cubic inches. But if you go by that then Chevy is wrong with the 396 big block so I am unsure exactly.

[Custom Mike]

Not too sure what the A/T would stand for other than Automatic Transmission, what make of car was it on? R/T would be Road/Track. I'll give the Chevy Small/Big block list a shot....

Small Blocks: 265, 283, 302, 305, 307, 327, 350, and 400 (Which came in Small and Big Block varieties)

Big Blocks: 348, 396, 400, 402, 409, 427, and 454. 572 is also available, but was never put in a production car from the factory, it's available as an aftermarket engine only.

So Bowtie guys, did I get it right?

[RodneyBad]

Dodge Small blocks.

273

318

340

360 (Mostly used in trucks)

Dodge Big Blocks.

383

392 Hemi

400 (Mostly used in trucks)

426 Hemi

440

[Custom Mike]

I read somewhere that a "big block" is an engine over 400 cubic inches. But if you go by that then Chevy is wrong with the 396 big block so I am unsure exactly.

Patrick, it's kind of confusing, isn't it? The Chevy 409 came from the 348, they look identical on the outside, the size difference is internal. Same with the 396, the 427 looks just like it, and I believe the 454 is very close to a 396 visually also, but I may be wrong there. The 400 is really confusing, one is based on the old 265 block, the other isn't. One Small block, one Big block, same cubic inch designation, I don't know what brought that on....some good stuff at lunch in the engine shop one day maybe....

[MachinistMark]

chevy also had a 366 big block. it was a medium-heavy duty truck motor

[Nova-ss]

Sounds right to me.small blocks are in most cases a smaller block size then the big blocks are,even if it is a 400 sm block.the big blocks wieght more then small blocks and are a different configuration then the big blocks.I think that is right.Thanks,Chris

[Longbox55]

Not too sure what the A/T would stand for other than Automatic Transmission, what make of car was it on? R/T would be Road/Track. I'll give the Chevy Small/Big block list a shot....

Small Blocks: 265, 283, 302, 305, 307, 327, 350, and 400 (Which came in Small and Big Block varieties)

Big Blocks: 348, 396, 400, 402, 409, 427, and 454. 572 is also available, but was never put in a production car from the factory, it's available as an aftermarket engine only.

So Bowtie guys, did I get it right?

Not too bad. A few minor corrections. The "400 Big Block" was actually the 402, it was simply rounded down to 400 for badging purposes. You also missed a few in the Big Blocks, there was also a 366 (Heavy truck), 430, 488, 502, and a 510. The 430, 488, and 510 were strictly aftermarket perfomance engine, the 502, while mainly an aftermarket crate engine, was available as a factory install in the GMC Yukon in 2000 in its 540 horse Ramjet version.

On the Small Blocks, you missed the 262 and 267, not really unexpected, as those engines were not produced for very long and were not very common when they were made.

[Custom Mike]

chevy also had a 366 big block. it was a medium-heavy duty truck motor

Thanks Mark, I know my memory isn't perfect, there's gonna be a few I missed.

Dodge Small blocks.

273

318

340

360 (Mostly used in trucks)

Dodge Big Blocks.

383

392 Hemi

400 (Mostly used in trucks)

426 Hemi

440

Rodney, you missed the 413 Max Wedge, a beast of a Mopar Motor!

[Custom Mike]

Not too bad. A few minor corrections. The "400 Big Block" was actually the 402, it was simply rounded down to 400 for badging purposes. You also missed a few in the Big Blocks, there was also a 366 (Heavy truck), 430, 488, 502, and a 510. The 430, 488, and 510 were strictly aftermarket perfomance engine, the 502, while mainly an aftermarket crate engine, was available as a factory install in the GMC Yukon in 2000 in its 540 horse Ramjet version.

On the Small Blocks, you missed the 262 and 267, not really unexpected, as those engines were not produced for very long and were not very common when they were made.

Thanks Bill, I never was into Chevy Trucks too much, so i wouldn't have known all of 'em anyway. I knew there was some strange thing about the 402, but couldn't recall it, I depend on guys like you clear up my foggy memory! I had no idea the 502 was actually available form the factory...they should have shoved it into a few passenger cars for fun!

[Aaronw]

I believe it has to do with the physical size of the block rather than actual displacement.

Chrysler's B series engine is considered a big block but it started with a displacement of 350 cubic inches and eventually developed into the 361, 383 and 400. The RB series is closely related (slightly taller block for a longer stroke length) and was available as the 413, 426 and 440.

GM's W series that Mike mentioned is also a big block and was available as a 348, 409 and 427.

[Longbox55]

Then you have engine like the Pontiac, where there are no "small" or "big" blocks, the blocks are the same on the outside from the little 287 all the way to 455.

[MachinistMark]

427 was not a w motor aaron

[Aaronw]

427 was not a w motor aaron

According to the Ultimate American V-8 Engine Data Book, the Chevrolet W was available as a 427. The better known 427 is part of the later Chevy big block that included the 396, 402 and 454.

[Longbox55]

The W engine was made as a 427, 1963 only. It was part of the Z-11 package that also included aluminum front fender, hood, battery tray, inner fenders, and front bumper on the Impala for drag racing. There was also a second 427 built that year, the Mark 2 "Mystery Motor", that shares none of it's parts with the earlier Mark 1 W block. The later 427, along with the 366, 396, 430, 454, 488, and the 510 are all Mark 4 engines. There was no Mark 3 other than experimentals. The Mark 5/Gen 5 was only offered as a 454, Gen 6 was built as 454, 502, and the 572. There is also one more that wasn't mentioned, as it was only built for a few years, and only used in 3/4 and 1 ton trucks, the 8.1 liter Gen 7. It shares little with the earlier engines, and is closer to a super sized LS block.

[Chas SCR]

Chevy, 502 and 572 are complete diffrent size block then the old 454 and 427. For the W 427 this was not a perduction motor and could not be listed as a normal motor in 63. The Pre-Z11 kits front fenders, hood, and front bumper only was also given out to 25 team drivers in 2nd week of Aug of 1962 so they could be ready for the US Nationals at Indy, A few of them ran them at the Detroit Worlds the week before Indy and also the first full 409/425hp service package two motor came in a car starting of Aug of 62.

Also Chevy had some crazy motor sizes in the mid 80s till the early 90s, Book would say one thing and the math would say some thing els when you was rebuilding it.

Seen a few 331, 305,307,302.

Pontiac also had 301,326,400 421

Some Ford motors also was the 488 Gorilla truck motor you could get as a crate motor in the 70s and early 80s.

Dodge or Ply, 318,340,360,

[Longbox55]

The 502 and 572 are built on the Tall Deck block. Still considered the same engine family. The 366 and 427 Truck engines are also built on the Tall deck block.

There were actually 57 of the W427 engine built and installed in Impalas as part of the Z11 package, by NHRA standards, it qualifies as a production engine.

[Danno]

Anybody confused yet? If not, hang in there ... you'll get there sooner or later!

Somebody mentioned the correct answer: external dimensions of the engine block casting itself dictate whether an engine is considered "small" or "large," not the cylinder displacement.

[Greg Myers]

This is the part I like, where, after a good basic question (there are no dumb questions) we get some good basic answers that cover the topic. Then the experts jump in, and no I don't know the difference between a 350 and a 361 MOPAR. Wouldn't know if it jumped up and bit me on the . . . well, you know.

My room mate in college had a '59 Dodge convertible with a big v-8 in it. Don't have a clue what it was. We did put a whole new exhaust on it though, used the flex pipe stuff. Worked really well bending all around everything.

[jeff ewaskey]

The big block Chevy 396 , 400 & 402 are all generally the same engine. In 1970, GM stared overboring the 396 blocks .030 which increased it to 402 cubes. The 400 designation was the same 396/402 engine but Chevy called it a 400 in pickup trucks and some full size vehicles. In high performance applications the 402 was still called a 396. Think I got all that right . Lol

[RodneyBad]

This is the part I like, where, after a good basic question (there are no dumb questions) we get some good basic answers that cover the topic. Then the experts jump in, and no I don't know the difference between a 350 and a 361 MOPAR. Wouldn't know if it jumped up and bit me on the . . . well, you know.

My room mate in college had a '59 Dodge convertible with a big v-8 in it. Don't have a clue what it was. We did put a whole new exhaust on it though, used the flex pipe stuff. Worked really well bending all around everything.

That's just soo Wrong in many ways.. LOL...

[imatt88]

Clear as mud!

[SuperStockAndy]

I read somewhere that a "big block" is an engine over 400 cubic inches. But if you go by that then Chevy is wrong with the 396 big block so I am unsure exactly.

If I'm correct, the 396 was actually a 402.

[Keef]

If I'm correct, the 396 was actually a 402.

your incorrect, the 402 was actually a 396 bored .030 over

The 396-cubic-inch (6.5 L) V8 was introduced in the 1965 Corvette as the L78 option and in the Z16 Chevelle. It had a bore of 4.094 in (104.0 mm) and a stroke of 3.76 in (96 mm), and produced 375 hp (280 kW) and 415 lb·ft (563 N·m). This version of the 396 was equipped with four bolt main bearing caps and was very comfortable with being operated in the upper 6000 rpm range.

Introduced in 1970, the 402-cubic-inch (6.6 L) was a 396-cubic-inch bored out by 0.030 in (0.76 mm). Despite the fact that it was 6 cubic inches (98 cc) larger, Chevy continued marketing it under the popular "396" label in the smaller cars while at the same time labeling it "Turbo-Jet 400" in the full-size cars.