The W Returns – Building a Chevy 409-CID “W” engine

June 8th, 2010

In 1961, Chevrolet introduced the new “W” engine, an enlarged and truly performance version of the 348-CID engine that had gone before. The 409 was the stuff of legends and was available in big bodied Chevys from 1961 through early 1965 when it was replaced by the first of the Mark IV big-blocks. Immortalized by the Beach Boys, who created the song “409” to sing its praises, the 409 was true to the hype of the car offered in a number of horsepower levels and with camshafts and carburetors appropriate for the ponies it generated.

When it debuted on Dec. 17, 1960, the 409 package was available on the Impala SS model with 360 HP (single Carter four-barrel carb). In 1962, Chevy upped the ante with a 380 HP version sporting the same induction system. In addition they offered a 409 HP edition matching  the one horsepower per cubic inch effort they delivered in 1957 with their fuel-injected 283 engine. The 409-HP engine wore a dual aluminum four-barrel intake manifold with twin Carter AFB carbs. But the best was still yet to come.

Rough and tumble, this ’61 Chevy will be the host organism for our new 409. Don’t worry, it already looks a lot better than this. Check out the rendering to look into the future.

In 1963, the 409 peaked with the highest horsepower rating it was to achieve, a 425-HP decal adhered to the air cleaner covering the twin Carter carbs, 11.25:1 compression pistons and solid lifter camshaft. Not to overlook those owners uninterested in having to set the valve lash every Saturday morning to ensure the highest rate of tune, a 340-HP engine with a hydraulic cam shaft continued to be offered from 1963 through 1965. There was a 409 for every taste.

For trivia buffs the 409 “W” engine had an even larger displacement and often forgotten race engine cousin that was to catch many a headline starting in 1963 when it was offered as a Regular Production Option (RPO) code. The 427 Z11 engine was to 409 fans what the original 426-Hemi engine was to Mopar 392-CID engine nuts. This 427-CID aluminum engine was a 13.5:1 compression beast that used a two-piece, high-rise aluminum intake manifold and allegedly produced only 430 HP. Clearly a ruse to throw off the competition, only 57 of these rare Z11s were ever built, but they were to cement the 409 legacy in the minds of Chevy racers and speed freaks forever.

The Muscle Car TV 409 shown here takes off where the legend ended in 1965. Today there is a host of new parts and pieces that every 409 fan — and those looking for a new way to motivate their classic Chevy — can appreciate. For the record, the “W” notation referred to the upside down “W” shape noted in the valve cover — amazing but true.

The engine shown here was designed for the “Muscle Car TV Red Sled” project car and uses the latest technology, including aluminum cylinder heads, forged aluminum custom pistons, dual quad aluminum intake with Edelbrock carbs, and lots more. When run on the “Muscle Car TV” dyno, the finished product cranked out peak performance figures of 497 HP and 525 lb.-ft. of torque, which is better than the original rating on the 430-HP Z11 with far better street manners, including the ability to use street fuels instead of the 100-plus-octane race gas needed for the 13.5:1 compression race engine.

As is clearly the case with this 409 engine, some things get better (and nastier) with age.



Rod bolts, main bolts and accessory kit

800.826.3045 (http://www NULL.arp-bolts


1.7:1 Magnum roller rockers

Hydraulic roller camshaft

800.999.0853 (http://www NULL.compcams

Denso Products

Iridium spark plugs

888.96.DENSO (http://www NULL.densoiridium

Doug Thorley headers

Ceramic-coated Tri-Y headers

800.347.8664 (http://www NULL.dougthorleyheaders

Eagle Specialty Products

Steel 4340 crankshaft

6.125-inch connecting rods

662.796.7373 (http://www NULL.eaglerodcom/)

Edelbrock Corp

Performer RPM cylinder heads

Performer dual quad air gap manifold

Edelbrock 600-CFM carburetors

Aluminum valve covers

Large oval cast air cleaner

Oil filler tube

310.781.2222 (http://www NULL.edelbrock

Lamar Walden Automotive

Machining and assembly

770.449.0315 (http://www NULL.lamarwaldenautomotive

Mallory Ignition

Unilite ignition and coil

216.688.8300 (http://www NULL.malloryperformance

Stage 8 Locking Fasteners

Header bolt locks (http://www NULL.stage8


Spin-on oil filter adapter

562.921.0404 (http://www NULL.tdperformance

Taylor Cable

Spark plug wire set (http://www NULL.taylorvertex


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