Mopar B and RB
Low-deck B engines (361s, 383s, and 400s) can be easily distinguished from raised-deck RB engines (413s, 426s, and 440s) by the location of the engine identification pad. On B engines, the pad, which is stamped with the engine displacement, is located on the passenger side of the block just below the distributor (A). The ID pad on RB engines is located at the front of the engine above the water pump housing (B) and may be obscured if an AC compressor is mounted.
Both ID pads include a stamped single-letter date code (starting with the letter A for 1965, B for 1966, etc.) and the displacement. A letter E stamped after the displacement indicates the engine has a cast crank.
Mopar LA Engines
Externally, small-block Chryslers all basically look the same, but they're easy to identify because the factory stamped them with an ID code on the front of the block just below the cylinder head on the driver side. The code is a series of numbers that indicate production location and date, as well as displacement. (Note: some 273s are stamped only "27".) Many 318s and most 340s and 360s also have the displacement cast as the last three digits of the casting number on the side of the block.
An easy way to spot a late externally balanced 340 or any 360 is to look for a balance weight on the harmonic balancer (right). You can differentiate 340s and 360s by the displacement cast as part of the casting number.
Mopar Poly 318
Produced from 1957 to 1966, the Polyspheric 318 shares the same displacement as its later and more popular kin (but not much else), and it's probably best avoided. You can easily spot one by its scalloped valve covers.
A quick way to differentiate between small-block (307, 330, 350, 403) and big-block (400, 425, 455) cylinder heads is by the casting identifier. Small-block heads are marked with a number cast into the lower left corner of the head over the exhaust port; big-block heads, like this one on a 455, have a letter in the same location.
The casting number on Olds engines is located at the front of the block on top of the timing gear housing. A nine-digit engine ID code is stamped on a pad directly below the Number One cylinder. The first digit is a 3, signifying the Oldsmobile division, followed by a single digit for the year, e.g. 2=1972, a letter designating the assembly plant, and a six-digit serial number that will match the VIN if the engine is original to the car. If you're searching for an Olds 455, here are the casting numbers to look for: 396021F ('68-'71); 396021Fa ('72-'76); and 231788L (service replacement).
Buick 350 and 455 engines can be identified by the location of the engine serial number on the block without actually decoding the number. On 350s, the serial number is stamped on the front of the block below the driver-side cylinder head. On 400s and 455s, the serial number is stamped on the block between the first two spark plugs and the exhaust manifold on the driver side.
On a Buick 455, the displacement is cast into the top of the bellhousing flange at the back of the block. On 350s, it's at the back of the intake manifold.
The AMC 290, 304, 343, 360, 390, and 401 all share the same external specifications, and the intake manifolds interchange. They can be identified by the cubic-inch displacement cast into the block on either side. The number is under the engine mount brackets, so you may need to feel it rather than see it.
On most Pontiac 350, 400, and 455 blocks manufactured after 1968, the cubic inch displacement is cast into the driver side of the block just in front of the first freeze plug (arrow). On 428 blocks, the displacement is cast upside-down near the center of the block, also on the driver side.
A three- or four-digit date code is located on the distributor pad at the back of the engine. The first letter indicates the month (A=January, B=February, etc.), the second and third digit correspond to the day of the month, and the last digit is the year. The last two digits of the year are also cast in large numbers near the distributor hole. Somebody screwed up on this 455 because one date says '75 and the other says '76.
Here are some other tips for dating and identifying Poncho blocks: (A) Pre-'67 blocks have two freeze plugs per side, while later blocks have three. (B) Prior to 1970, blocks were drilled and tapped with two motor mount holes; after '70, there were five holes, but on some blocks, only three are drilled and tapped. (C) Under the intake manifold, the last two digits of the displacement (i.e., 55 for 455, 50 for 350, 00 for 400) are cast into the center of the lifter valley.
FE--five cover bolts
Ford Engine Families
Even a hard-core Ford guy will tell you that some engines in the Blue Oval family are very difficult to distinguish externally, thanks to the fact that Ford often used identical blocks to assemble different displacement engines. For example, both the 429 and 460 big-blocks (385 series) and the 351M and 400M share identical blocks and heads. Ford was pretty good about pasting engine identification stickers on the valve covers, but if either the heads or valve covers have been replaced, you're left in the dark. The only way to identify these engines for sure is to check the throw of the crank.
From 1965 on, Ford engines were equipped with a stamped metal ID tag, which carries the displacement and model year among other info. This tag is generally attached to either the intake manifold in front of the carb or to the ignition coil on the front of the engine, if you're lucky enough to find an untouched original. This tag was on a '65 352 FE.
The first two digits of cast-in Ford part numbers are useful for dating a part (A). The first letter designates the decade (C='60-'69, D='70-'79, E='80-'89), and the number indicates the year. This is a '64 casting. On 289/302 small-blocks, the displacement is also cast into the manifold (B), but this can be misleading because manifolds are interchangeable.
Ford 429 vs. 460
Although the 429- and 460ci big-blocks can be distinguished from other Ford engines by their seven valve cover bolts, the only way to tell the 429 from the 460 is by the length of the stroke--3.59 vs. 3.85 inches. If measuring doesn't work or if the pan is already off the engine block, the casting number on the crank readily separates the two.
|CID||Year||Crank Casting Number|
|460||'68-'78||2Y, 2YA, 2YAB, 2YABC|
The 351 Cleveland and the 351/400M have similar heads with eight cover bolts, but they have different bellhousing patterns. The Cleveland shares a bellhousing pattern with the small-block Windsors (shown, on left), while the 351M/400 block (right) uses the larger pattern of the 429/460 big-blocks. Note the different spacing between the upper two sets of bolt holes (arrows)
Ford 351 Windsor
Ford made three different engines that carried a 351ci displacement, leading to a great deal of confusion. The popular 351 Windsor, which has six-bolt valve covers, is basically a raised-deck version of the 289/302 small-blocks. The taller deck surface is visible at the front and back of the block. These two ribs (arrows) at the back near the distributor clearly distinguish this as a 351 Windsor.
Ford 351 Cleveland
The 351 Clevelands and 351/400M engines have large, square heads with splayed valves and eight cover bolts. Cleveland heads are marked with a large numeral 2 or 4 in the upper corner of each head, signifying either a two- or four-barrel application. Produced only with two-barrel carbs, 351M/400 engines either have an "M" on each corner or no mark at all. The only way to tell a 351M from a 400 is by measuring the stroke. The 351M stroke is 3.50 inches; the 400M stroke is 4.00 inches.
Ford FE Series
The FE series of engines, produced in displacements of 332, 352, 360, 361, 390, 406, 410, 427, and 428 ci between 1958 and 1976, has a five-bolt valve cover and Chevy-style water pump and is also identifiable by its intake manifold, which forms part of the valve cover surface.
The torque-monster 472 and 500ci Cadillac motors share the same block casting number, so identification must be made by checking the crank stroke: The 500 has a 4.3-inch stroke; the 472's is 4.060 inches. With the pan off, crank ID is easy since only three casting numbers were used. All 472 cranks have a casting number ending in 424, which is cast on the edge of the third crank counterweight from the front. The 500s used cranks ending in either 094 or 793, which is cast on the side of the counterweight between the No. 3 and No. 4 crank throws. From '70 to '74, 500s came only in front-wheel-drive Eldorados; in '75 and '76, they were available in all the large models. CC
While compiling this spotter's guide, we relied on several excellent books loaded with info about engine identification. For the popular brands like Chevy, Ford, and Mopar, there are many books available. As a result of their tremendous popularity and the availability of good factory records, part and casting numbers for Chevrolet engines are particularly well documented. A few of our favorites are MSA-1's series of pocket-sized part and casting number guidebooks and Alan Colvin's Chevrolet By The Numbers series published by Robert Bentley. Other useful books are High Performance Ford Engine Parts Interchange, by George Reid, and Ed Staffel's Small-Block Chevy Parts Interchange Manual, both published by CarTech.
Information is tougher to come by for Buick, Olds, and Pontiac, but we gleaned all we could from Pete McCarthy's book, Pontiac Musclecar Performance 1955-1979, Dennis Mothershed's Oldsmobile Numbers Swap Meet Guide, available from Dick Miller Racing Inc., and Steven Dove's Guide to Buick Performance Engines, which can be ordered from Poston Enterprises. We also picked the brain of Cadillac Larry Kruzick of Cadillac Motorsports Development. Check the source box for more on ordering these books.
American Musclecar Publications
P.O. Box 460723
11311 Pendleton St.
Cadillac Motorsports Development
2810-6 Parkway St
P.O. Box 427
11481 Kost Dam Rd.
206 N. Main St.
Dick Miller Racing Inc.
6856 Keystone Dr.
Robert Bentley Publishers
1033 Massachusetts Ave.
7677 S. Alameda
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