Chevrolet L78


The L78 was a big-block engine|big-block] engine produced by Chevrolet between 1965 and 1970. Rated at for its first year, the rating dropped to in subsequent years. Between 1966 and 1969 it was the most powerful Regular Production Option engine available in Chevrolet's intermediate line, making it a highly-collectible muscle car engine today.

History

The second-generation Chevrolet big-block engine was introduced at the 1963 Daytona 500 as the Mark II. It entered production in mid-1965 as the Mark IV "Turbo-Jet," phasing out the first-generation W-series big-block. In its first year, the 396 was available as the L78 option in Corvettes and full-sized models, and as the L37 in the intermediate model. These engines differed only in that the L78 had a solid-lifter camshaft, while the L37 had a hydraulic lifter cam shaft.
In 1966 the L78 was available exclusively in the intermediate line. For 1967 the engine was additionally available in Chevrolet's new pony car, the Camaro. The following year the motor became available in the compact Chevy II / Nova|Chevy II] as well.
For the 1970 model year the 396 was bored, resulting in a engine. Despite this, the motor was still badged as a 396. 1970 was also the final production year for the L78. Although 1970 LS6 Chevelles are generally more collectible today, 1970 L78 Chevelles are in fact rarer.
Between 1966 and 1969 the L78 was the highest-horsepower engine available in Chevrolet's intermediate line via a Regular Production Option.

L89

A version of the L78 was also produced with aluminum cylinder heads and sold as RPO L89. This option did not change performance, but reduced engine weight by roughly. This engine was available from 1968 to 1970.

Production numbers

L78

Full Intermediate Compact Pony Sports
19651,8382,157
19663,099
19676121,138*
19684,7516674,575**
19699,4864,9514,889
19702,1443,765600

  • * 54 of these were converted into L72 Yenko Super Camaros.
  • ** 64 of these were converted into L72 Yenko Super Camaros.

L78/L89

Intermediate Compact Pony
1968272
1969400311
197018