A Little Tech & Trivia about the LS5 engine

1970:
The LS5 engine was the base engine for the Z15 SS454 Equipment package. The engine is listed as RPO LS5 on the buildsheet but, then again, other RPO codes are listed on the buildsheet and they are listed because they are all part of the Z15 SS454 Group package and not available individually.

It should be noted that although the letter shown below indicates the availability of the LS5 engine for "...Chevelle, El Camino and small wagons..." no NON-SS-optioned Chevelle, El Camino, or small wagon has surfaced to date.

October 30th, 1969

TO ALL DEALERS:

Please be advised that effective immediately, the LS3 engine for Chevelles, El Caminos, and small wagons may be submitted for production. Also, new 360-HP SS454 option Z15 for Malibu coupe and convertible or El Camino, may be submitted with either M40 transmission, or new option M22 4 speed special transmission. Z15 includes same axle ratio and basic components as Z25 SS396 except engine. In addition, new 450-HP 454 engine may be ordered with Z15 as option LS6 immediately. Prices of these new options will be forwarded as soon as possible.

In conjunction with the release of LS6 450-HP engine, the 375-HP Engine Option L78 and the L78/L89 for use with SS 396 is in process of being cancelled, and further orders for these options should not be submitted.

Very truly yours,

W.C. Kuhn
Zone distribution Manager

The LS6 engine was an option on top of the Z15 SS454 Equipment package. By knowing how many Z15 SS454 Equipment package options were sold, 8773, and subtracting the number of LS6 options, 4475, one is left with 4298 with the base LS5 engine.

1971/1972:

In 1971 & 1972 the Z15 SS454 Equipment option was reclassified as simply the Z15 SS Group option. Z15 SS Group was now a dress-up option and not a performance option. Any optional V8 engine could be ordered with RPO Z15 which included the 350-2 (L65), 350-4 (L48), 402-4 (LS3) or 454 (LS5). While the LS5 engine choice mandated the Z15 SS Group option the other 3 engines did not and could be ordered on any other Chevelle series and body styles without the Z15 option while the LS5 was limited to Malibu sport coupes, convertibles, and pickups and mandated the Z15 option.

Bottom line for 1971 and 1972:
* If the Chevelle has a factory 454 engine, it must be a Malibu sport coupe, Malibu convertible, or Malibu pickup and would have the SS option.
* Any 350-2, 350-4, 402-4 factory engine in a Malibu sport coupe, Malibu convertible, or Malibu pickup may or may not have the SS option.
* Any series/model EXCEPT the Malibu sport coupe, Malibu convertible, or Malibu pickup could have any V8 engine except the 454 and could not be ordered with the SS option.