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1966 SS 396

1966 SS 396 Engine Codes

The 396 8-cyl engine was only available in the 13817/67 SS 396 series and both the 13480 and 13680 El Camino. The L35 396 cid 8-cyl engine was the base, or standard, engine in the SS 396. GM reports 1,865 L35 engines ordered as options and these would have been installed in the El Camino series.

1966 396 V8 Engine Production

The base engine for the SS396 series for 1966 was the L35 396cid 325hp engine. This engine (along with the L34 and L78) was also an optional engine in the El Camino and 1,865 L35 engines were sold in the El Camino body style. There were 72,272 SS396 SS 396s, sport coupes (66,380) and convertibles (5,393), sold. There is no way to know how many of the base L35 engines were sold in SS396 sport coupes and/or convertibles. One can only take the number of L35 options known to be sold in the El Camino body style (1,865) and subtract that from the total number reported by Tonawanda and arrive at a number that would include Total L35 SS396 Chevelles and Service Engines.

One cannot take the number of L34 or L78 engines into account for SS396 sales only since these were also available in the El Camino and only a total number of L34 and L78 options are known; what body style they went into is not known. Since it cannot be determined how many L35 engines were sold in the base SS396 series (Total L35 Engines) and the number of L35 service engines cannot be determined.

L35 engines could be equipped with either a Rochester (or Carter equivalent) Quadrajet carburetor or Holley carburetor; all L34 and L78 engines were equipped with a Holley carburetor.

The base 325-hp L35 engine with snorkel air cleaner assembly. All 396 cid engines came with flash chromed rocker arm covers, a flash chromed air cleaner assembly lid, and this instance on an L35 engine with positive ventilation, a flash chrome oil breather. Note the carburetor return spring is attached to the upper alternator brace. The 1967 upper alternator brace did not have this provision. See 1967 Engines page.

When equipped with GM's Air Injection Reactor emission system (RPO K19), the oil breather was replaced with a hose running from the oil breather location to the base of the air cleaner assembly and is referred to as a 'closed positive ventilation' system. Crankcase vapors that would normally have escaped into the air from the oil breather cap are now directed back into the airflow to the carburetor.

The 360-hp (RPO L34) engine came with the same flash chrome rocker arm covers but sported an open element air cleaner assembly with a flash chrome lid. All 360-hp engines were equipped with a closed positive ventilation system - note the hose running from the rocker arm cover to the base of air cleaner assembly.

This 360-hp engine is outfitted with GM's Air Injection Reactor emission system (RPO K19).

The special high performance 375-hp (RPO L78) engine featured a solid lifter camshaft, bigger rectangular port heads, an aluminum intake manifold, and bigger Holley carburetor. Note the deep groove pulley on the alternator to help retain the alternator belt at high rpms.

Another feature on the L78 engine was this idler pulley mount on the passenger side cylinder head.

The underside of the open element air cleaner assembly lid with service information.

Camshaft Specifications

Note the oil groove in rear cam journal of this 396 V8 camshaft on the left. Both 1965 and 1966 396 V8 engines require this groove along with corresponding rear cam bearing. Most aftermarket camshaft manufacturers DO NOT list the 65/66 396 V8 in their catalogs due to this groove. However, any later camshaft will work if grooved and most aftermarket cam suppliers will either groove the cam for a nominal fee or send you the specifications so you can have your local machine shop perform the operation